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To evaluate the morpho-physiological characteristics of some cool-season turfgrass species under shade stress, an experiment was conducted outdoor in two subsequent years. Then, tall fescue, as the best-recognized turf from the former test, was exposed to combined drought and shade stress, aiming to measure to what extent shade can decrease turfgrasses water consumption and alleviate drought effects. The first test included 35 treatments at 7 different levels of continuous and temporal shade conditions in the morning and afternoon (60% and 80%) and full sunlight, and 5 cool-season turfgrass species, i.e., tall fescue (Festuca arundinacea Schreb.), red fescue (Festuca rubra L.), perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.) and sheep fescue (Festuca ovina L.)]. The second test was consisted of 9 treatment, including 3 different irrigation intervals (i. e. 3, 6, and 9 days), 3 shade stress (i.e. full sunlight, 60% and 80% permanent shade), and 3 replications. Seeds of different cool-season turfgrass species were sown in April 2015 and 2016 in a loamy soil. Treated turfgrasses were evaluated for morpho-physiological and biochemical characteristics. Results showed that in the first test tall fescue has the highest quality in terms of morpho-physiological characteristics at a high level of shade stress (80% continuous shade). Perennial ryegrass and Kentucky bluegrass showed weak tolerance to shade stress conditions. The 80% constant shade had the greatest influence on turfgrass qualitative and quantitative traits, but in some cases did not show a significant difference between temporal shades. Turfgrasses quality decreased by increasing the intensity and duration of shade; however tall fescue was an excellent turfgrass species under shade stress conditions. Although visual quality, tiller density, and total chlorophyll content of tall fescue were significantly reduced by less frequent irrigation, they were improved by shade treatment compared with control plants. In addition, tall fescue has the highest amount of proline, catalase activity, starch, and reducing sugars under 9 days of drought and 60% shade stress. This is the first report of the interaction of shade and drought stress on the biochemical and morpho-physiological responses of tall fescue plants.

This research was carried out in the field of research and application of the Faculty of Agriculture at the Osman Bey Campus of Harran University during the 2015-2016 summer breeding season in Sanliurfa. In the research; tall fescue (Festuca arundinacea), the British grass (Lolium perenne), chewing red fescue (Festuca rubra L. subsp. Commutator), creeping red fescue (Festuca rubra L. subsp. rubra), sheep fescue (Festuca ovina), Kentucky bluegrass (Poa pratensis) was used as a material and the random blocks were set up with 3 replications according to the trial design. In this study; turf wet grass yield (kg da-1), grass dry grass yield (kg da-1), emergence rate (day), winter resistance (1-9), covering speed (day), coating degree (%), leaf texture (1 -9), number of siblings (1-5), and degree of sparseness (1-9) were examined. According to the trial findings; It would be appropriate to use the Golden Gate variety of the reed ball (Festuca arundinaceae) of the warm season grass species that can be recommended for the ecological conditions of Sanliurfa.

Increased nitrogen (N) availability induced by fertilizer use, rapid urbanization, and livestock cultivation has important effects on the biogeochemical cycles of plant N and phosphorus (P). Knowledge of the long-term N enrichment effects on the biogeochemical cycling of N and P via plant ecological stoichiometry and nutrient resorption remains limited. Nutrient resorption plays an important role in the plant nutrient economy and nutrient cycling. A three-year field experiment was performed to test the effects of N addition on leaf nutrient resorption of two dominant grass species (Leymus tiansecalinus and Festuca ovina) from an 11-year grassland experiment involving four N levels (0, 30, 90, and 150 kg N ha−1 year−1) in an alpine grassland of Tianshan Mountains in northwestern China. Nitrogen addition significantly increased aboveground biomass (AGB) and soil N availability. The N concentrations and N:P ratio in mature and senesced leaves consistently increased with increasing N across all three years. The P concentrations in mature and senesced leaves notably decreased with increasing N. The N addition resulted in decreased N resorption efficiency (NRE) and increased P resorption efficiency (PRE). The divergent responses of plant N and P resorption and N:P ratios resulted in the decoupling of the plant internal nutrient cycles for both grass species, attributed to increased soil N availability and nonsignificant effects on soil available P caused by N addition. In addition, the N:P resorption ratios were negatively correlated with increasing N levels, suggesting different sensitivities of plant N and P to N addition. The aboveground production of both grass species was positively correlated with PRE and negatively correlated with NRE. Under the background of the currently high and steadily increasing atmospheric N deposition, the imbalance of plant nutrient cycling will likely alter plant community compositions and subsequent litter decomposition, ultimately affecting ecosystem stability and function.

Water stress associated with drought-like conditions is a major factor limiting plant growth and impacts productivity of natural plant communities and agricultural crops. Molecular responses of plants to water stress have been studied most extensively in model species and crops, few of which have evolved natural drought tolerance. In the current study, we examined physiological and transcriptomic responses at multiple timepoints during increasing water stress and following initial recovery from stress in a drought-tolerant C3 species, Festuca ovina. Results demonstrated non-linear transcriptomic changes during increasing stress, but largely linear declines in physiological measurements during this same period. Transcription factors represented approximately 12.7% of all differentially expressed genes. In total, 117 F. ovina homologs of previously identified and molecularly characterized drought-responsive plant genes were identified. This information will be valuable for further investigations of the molecular mechanisms involved in drought tolerance in C3 plants.

The study results of hoofed animals impact on vegetation in aviaries of different size of the Volyn Regional Department of Forestry and Hunting are presented. The reaserch sites are laid in forest stand, which belonged (before the construction of the aviary and the arrangement of the feeding area) to one taxonomic department that determines their forestry-taxonomic identity what allows to apply the method of comparative ecology. The impact of hunting hoofed animals on forest vegetation was studied in aviaries and forest stands of Gubynsky, Karasynsky and Muravyshchansky forestry units, which are part of the structure of state enterprises "Volodymyr-Volynske forestry", "Manevytsia forestry" and "Kivertsy forestry", respectively. In oak stands of the aviary of Gubinsky forestry for breeding Sus scrofa, which has been operating since 2010, as of 2017, a twofold decrease in the species composition of vascular plants was observed. Outside the enclosure, 2 times more viable self-seeding and undergrowth of Populus tremula, Ulmus scabra – 8 times, and Sambucus nigra – more than 2 times were recorded. The coefficient of similarity between the grass cover inside and outside the enclosure is insignificant - 9.5%. Within the enclosure, a slight change in the sanitary condition category of such tree species as Salix caprea, Betula pendula, Populus tremula, Quercus robur was registered. As a result of exposure of wild boar within the enclosure, the sanitary condition of Carpinus betulus trees has changed to significantly weakened compared to healthy outside the enclosure. As of 2017, the grass cover restoration was registered in the aviary of Karasinsky forestry for breeding Sus scrofa, which operated from 2004 to 2010. In aviary conditions the dominant herbs are Vaccinium myrtillus, Vaccinium vitis-ideaea, Calamagrostis epigeios, Pteridium aquilinum and Pleurozium schreberi. The projective cover is dominated by Vaccinium myrtillus, Calamagrostis epigeios and Pleurozium schreberi, their total abundance is 41%. The coefficient of similarity of grasses in the pine-birch stand of the aviary and outside it is 61.5%. Within the aviary of Muravyshchansky forestry, where Bison bonasus, Cervuselaphus, Sus scrofa are kept, the areas of intensive influence of hoofed animals on forest vegetation are feeding grounds. Self-seeding, undergrowth and undergrowth were not found in pine-birch stands within the existing feeding site. Crops and weeds that are not typical for forest stands have been found in the vegetation within the feeding site. A total of seven grass species were identified, including a cultivated plant (Avena sativa) and two weeds (Calysteria sepium, Chenopodium album). Cultivated plants enter the forest environment together with the fodder they feed hoofed animals. It was found out that with the cessation of animal feeding, the composition of tree species and undergrowth species on the feeding site was restored and is identical to the vegetation outside it. Four years after the cessation of feeding of hunting animals, grain crops and weeds fall out of the grass cover of the former feeding ground and the forest environment is restored. There are 25 species of herbs registered here. The most common are Festuca ovina, Hieracium pilosella, Vaccinium myrtillus and Calysteria sepium. Hylocomium splendens (12%) and Vaccinium myrtillus (8%) predominate in the projective cover. Coefficient of similarity of the grass cover is 26.7%. The sanitary condition of wood species on the functioning feeding site has not changed significantly.

The regrowth of the aboveground biomass of certain plant species after complete or partial defoliation in highlands can depend on competition with neighboring plants, as well as on the level of availability of soil resources, primarily mineral nutrients (especially N and P). A 3-year full-factorial experiment on the effect of three defoliation regimes (control and single and double mowing at the soil level per season), enrichment of soil with N and P, and removal of neighboring plants (competition reduction) on the shoot number and aboveground biomass of three plant species (Anemone speciosa, Festuca ovina, and Oxytropis kubanensis) in alpine heaths was carried out (in total, 12 variants in 10 replications). It is shown that the removal of competing vegetation in low-productive communities of alpine heaths does not contribute to the biomass recovery after defoliation, unlike the addition of NP fertilizers. The regrow of a nitrogen-fixing legume did not depend on the availability of soil resources.

Festuca ovina is a fine fescue that is used as a low-input turfgrass. The ploidy levels of F. ovina accessions held by the USDA National Plant Germplasm System (NPGS) are unknown, limiting the use of the germplasm in breeding programs. The objective of this study was to determine DNA content and estimate ploidy of these 127 accessions. Among the accessions, we identified a wide range of ploidy levels from diploid to octoploid. We also found the accessions with higher ploidy levels usually had larger seed size. These results will be informative to plant breeders and researchers using germplasm from the F. ovina collection and point to challenges in maintaining polyploid, outcrossing germplasm seed stocks in common nurseries.

Orman içi meralar gerek evcil gerekse yaban hayvanlarıaçısından önemli bir kaba yem kaynağıdır ve ülkemizde bu alanların durumuhakkında yeterli kayıt yoktur. Bu çalışma, Sarıkamış sarıçam (Pinus sylvestris L.) ormanlarında ormaniçi meralarının bitki örtüsünün belirlenmesi amacıyla yürütülmüştür. İncelenenmera kesimlerinde toplam 63 bitki türüne rastlanmış olup, kesimlerde hakimbitki türleri buğdaygillerden koyun yumağı (Festucaovina), yumrulu salkımotu (Poabulbosa), baklagillerden ise çayır üçgülü (Trifolium pratense) olduğu tespit edilmiştir. Çalışma alanındabotanik kompozisyonda ortalama olarak buğdaygiller %51.01, baklagiller %17.50ve diğer familyalar ise %31.48 oranında tespit edilmiştir. Toprağı kaplamaoranı ortalama %24.56 olarak belirlenmiştir. En yüksek mera kalite derecesi 53.21ile seyrek kesimde, en düşük mera kalite derecesi ise 32.16 ile kapalı kesimdeolduğu belirlenmiştir. Mera durum sınıfı ve sağlığı yönünden açık kesimriskli orta, seyrek kesim sorunlu iyi ve kapalı kesim ise sorunlu ortasınıfında yer almıştır. Mera kesimleri arasındaki benzerlik indeksinin %31.5ile %47.5 arasında değiştiği belirlenmiştir., The forest gaprangelands are an important source of forage for both domestic and wildanimals and there are not enough records about the status of these areas in ourcountry. This study was carried out in Sarıkamış scotch pine (Pinus sylvestris L.) forests in order todetermine the vegetation of forest gap rangelands. A total of 63 plant specieswere found in the pasture sections examined. The dominant plant species inrangelands sites were sheepfescue (Festuca ovina) and bulbous bluegrass (Poa bulbosa) of grasses and red clover (Trifolium pratense) of legumes. In the study area, botanical compositionwas determined as 51.01% grasses, 17.50% legumes and 31.48% other plantfamilies. The canopy coveragerate was determined as 24.56% on average. The highest rangeland quality degreewas 53.21 in sparse rangeland and the lowest rangeland quality degree was 32.16in covered rangeland site. For rangeland health; uncovered rangeland site wasevaluated as “Risky-Fair” class, sparse rangeland site was evaluated as“Unhealthy-Good” class and covered rangeland site was evaluated as“Unhealthy-Fair” class. The similarity index was found from 31.5% and 47.5%among rangeland sites.

The aim of the presented research was to assess the initial growth rate of selected 5 grass species in order to determine their suitability for quick and effective infestation of roadside embankments in two sowing dates (spring and late autumn). The research was carried out on a bank situated along the national road S17. Measurements of root length and height of seedlings of each species were made on 10, 20, 30, 40, 50 and 60 days from the date of sowing. It has been shown that in the conditions of the experiment the grass species assessed differ in the rate of initial growth. Sowing dates had significant impact on the rate of root elongation and growth of seedlings of the studied grass species, because on objects with late autumn sowing date, all species and varieties were characterized by the shortest roots and the lowest seedlings. In both sowing dates, regardless of year of research, L. perenne seedlings were characterized by the longest roots and the highest seedlings in comparison to other species. In turn, seedlings of P. pratensis regardless of the year of studies were characterized by the shortest roots and the lowest seedlings in comparison to other species.

Herbivory is one of the key drivers shaping plant community dynamics. Herbivores can strongly influence plant productivity directly through defoliation and the return of nutrients in the form of du ...

The aim of this study was to screen plant species for remediation of oil-polluted soil in a semi-arid loess area. Pot experiments were conducted to test six indigenous plant species: ryegrass (Lolium perenne), tall fescue (Festuca ovina), wheatgrass (Agropyron cristatum), alfalfa (Medicago sativa), erect milkvetch (Astragalus adsurgens), and caragana (Caragana korshinskii). Loessial soil was spiked with crude oil at five pollution levels (0, 0.5, 1, 2, and 4%, w/w). We analyzed plant growth parameters at different stages, soil oxidoreductase activities, and oil degradation rate under different treatments. Soil pollution by oil negatively affected the germination rate, plant height, and biomass of all six species while inhibiting soil dehydrogenase and catalase activities. These inhibitory effects increased with increasing oil pollution level, with 2% and 1% being the critical levels at which plant growth and soil oxidoreductase activities were significantly inhibited, respectively. Both oxidoreductase activities in the rhizosphere soil were significantly higher than those in the bulk soil, which led to a considerable increase in the degradation rate of total petroleum hydrocarbons (TPHs) in the rhizosphere. The plants showed varying remediation effects in the oil-polluted soil. Erect milkvetch and caragana showed potential for remediation of soil below the 0.5% pollution level, alfalfa for soil below the 1% pollution level, and ryegrass, tall fescue, and wheatgrass for soil below the 4% pollution level. The oil pollution level was negatively correlated with plant height, biomass, oxidoreductase activities, and TPH degradation rate for the six plants (p

Summary • This study examined morphological and topological responses of nodal root axes to defoliation in a fast- and a slow-growing grass species. • Vegetative tillers of both Lolium perenne and Festuca ovina were grown on slant boards and either left intact or subjected to repeated defoliation, under both a high nitrogen (N) and a low N supply. Root length, diameter and branching characteristics were measured on individual nodal root axes. • The total axis root length of F. ovina was less when plants had been defoliated. Root axis weight, primary root axis length and primary root diameter were also less with defoliation than an undefoliated control, under high N. Under low N conditions the root axes of F. ovina had a more randomly branched topology without defoliation. For L. perenne under low N conditions, the length of the primary root axis was longer with defoliation than in an undefoliated control, while the primary root axis diameter decreased. By contrast to F. ovina, the root axes of L. perenne had a more randomly branched topology without defoliation only when supplied with high N. • The greatest plasticity in branching caused by defoliation was observed under high N for L. perenne and under low N for F. ovina. Although grass root axis topology has, in general, a herringbone in structure, the nodal root system can alter root axis structure in response to defoliation.

Microbial immobilization may decrease the inorganic nutrient concentrations of the soil to the extent of affecting plant nutrient uptake and growth. We have hypothesized that graminoids with opportunistic nutrient-acquisition strategies are strongly influenced by nutrient limitation imposed by microbes, whereas growth forms such as dwarf shrubs are less affected by the mobilization–immobilization cycles in microbes. By adding NPK fertilizer, labile C (sugar) and fungicide (benomyl) over a 5 yr period in a fully factorial design, we aimed to manipulate the sink–source potential for nutrients in a non-acidic heath tundra soil. After 2 yr, N and P accumulated in the microbial biomass after fertilization with no change in microbial C, which suggests that nutrients did not limit microbial biomass growth. After 5 yr, microbial C was enhanced by 60% in plots with addition of labile C, which points to C-limitation of the microbial biomass. Microbial biomass N and P tended to increase following addition of labile C, by 10 and 25%, respectively. This caused decreased availability of NH4+ and P, showing close microbial control of nutrient availability. The most common graminoid, Festuca ovina, responded to fertilizer addition with a strong increase, and to labile C addition with a strong decrease in cover, providing the first direct field evidence that nutrient limitation imposed by immobilizing microbes can affect the growth of tundra plants. Also in support of our hypothesis, following addition of labile C the concentrations of N and K in leaves and that of N in roots of F. ovina decreased, whilst the demand of roots for P increased. In contrast, the most common dwarf shrub, Vaccinium uliginosum, was only slightly sensitive to changes in resource availability, showing no cover change after 4 yr addition of labile C and fertilizer, and little change in leaf nutrient concentrations. We suggest that the differential responses of the two growth forms are due to differences in storage and nutrient uptake pathways, with the dwarf shrub having large nutrient storage capacity and access to organic forms of N through its mycorrhizal association. While the fungicide had no effect on ericoid mycorrhizal colonization of roots or symbiotic function inferred from plant 15N natural abundance, it decreased microbial biomass C and N after 2 yr. Throughout the fifth season, the availability of soil NO3− and inorganic P was decreased with no change in microbial biomass C, N or P, suggesting a negative impact of benomyl on N and P mineralization.

Vegetation recovery in severely disturbed alpine ecosystems can be accelerated through active restoration measures. This study evaluated the short-term effects of two restoration treatments, planting of propagated native Salix (willow) shrubs in three different densities (1, 2.5, and 4 plants/m2) and seeding of the native grass Festuca ovina (sheep fescue), in a disturbed alpine heathland. We evaluated natural vegetation recovery (i.e. vegetation cover, vascular plant species richness, and Salix recruitment) in permanent plots, 5 years after the implementation of restoration measures. The results showed that both treatments had positive but different effects on vegetation recovery; Salix plantings (with densities ≥2.5 plants/m2) increased vascular plant species richness and recruitment of Salix seedlings, whereas seeding of F. ovina increased bottom and field layer cover. Our results also show the importance of soil conditions for vegetation recovery, as moister plots with a higher percentage of fine soil substrate had a higher vegetation cover and vascular plant species richness. This study shows that different restoration treatments can work complementary and also highlights the importance of considering different indicators of vegetation recovery when evaluating the effectiveness of restoration measures.

Festuca ovinais a fine fescue that is used as a low-input turfgrass. The ploidy levels ofF. ovinaaccessions held by the USDA National Plant Germplasm System (NPGS) are unknown, limiting the use of the germplasm in breeding programs. The objective of this study was to determine DNA content and estimate ploidy of these 127 accessions. Among the accessions, we identified a wide range of ploidy levels from diploid to octoploid. We also found the accessions with higher ploidy levels usually had larger seed size. These results will be informative to plant breeders and researchers using germplasm from theF. ovinacollection and point to challenges in maintaining polyploid, outcrossing germplasm seed stocks in common nurseries.

Interest in abandoning herbicide fallow as the standard in-the-row orchard floor management system continues unabated. Despite research efforts, available relevant data remain insufficient to formulate reliable recommendations for individual site conditions. A long-term experiment was therefore initiated in a temperate climate area in south-western Poland. ‘Ligol’ and ‘Pinova’ cultivar apple trees were planted in an unirrigated orchard in 2004, with treatment plot tree-rows mulched and control plots maintained with herbicide fallow. In 2016, black woven polypropylene fabric and Agrostis vulgaris With. and Festuca ovina L. living mulches were compared with the herbicide fallow in terms of their effect on soil properties, tree nutrient status and yields. While the living mulches had a positive influence on soil porosity, humus content and pH, there were substantial yield reductions; arguably due to competition for water. It is therefore important that more intensive methods of understory vegetation suppression are explored and more competition-resilient rootstocks sought to counteract yield loss. The polypropylene cover was primarily associated with a decreased leaf K:Ca+Mg ratio. A synthetic mulch is a viable choice for certain rain-fed orchards.

The two factors defining male reproductive success in plants are pollen quantity and quality, but our knowledge about the importance of pollen quality is limited due to methodological constraints. Pollen quality in terms of chemical composition may be either genetically fixed for high performance independent of environmental conditions, or it may be plastic to maximize reproductive output under different environmental conditions. In this study, we validated a new approach for studying the role of chemical composition of pollen in adaptation to local climate. The approach is based on high‐throughput Fourier infrared (FTIR) characterization and biochemical interpretation of pollen chemical composition in response to environmental conditions. The study covered three grass species, Poa alpina, Anthoxanthum odoratum, and Festuca ovina. For each species, plants were grown from seeds of three populations with wide geographic and climate variation. Each individual plant was divided into four genetically identical clones which were grown in different controlled environments (high and low levels of temperature and nutrients). In total, 389 samples were measured using a high‐throughput FTIR spectrometer. The biochemical fingerprints of pollen were species and population specific, and plastic in response to different environmental conditions. The response was most pronounced for temperature, influencing the levels of proteins, lipids, and carbohydrates in pollen of all species. Furthermore, there is considerable variation in plasticity of the chemical composition of pollen among species and populations. The use of high‐throughput FTIR spectroscopy provides fast, cheap, and simple assessment of the chemical composition of pollen. In combination with controlled‐condition growth experiments and multivariate analyses, FTIR spectroscopy opens up for studies of the adaptive role of pollen that until now has been difficult with available methodology. The approach can easily be extended to other species and environmental conditions and has the potential to significantly increase our understanding of plant male function.

Mulching has increasingly become a standard method used in maintaining low-input lawns. This can be attributed to cost-savings, as these maintenance systems do not require loading and hauling of grass clippings. It is also possible to reduce the amount of nitrogen (N) fertilization and thus save on fertilizer costs. The effects of mowing management and rate of nitrogen fertilization on quality and growth of urban lawns were studied in a field trial during 2007–2012 on lawns newly sown in autumn 2006 and consisting of a grass–legume mixture ( Lolium perenne 25%, Poa pratensis 25%, Festuca rubra 30%, Festuca ovina 5%, Anthoxanthum odoratum 5%, Cynosurus cristatus 5%, Trifolium repens 3%, Lotus corniculatus 2%). Nitrogen was used at three application levels: 0, 50 and 100 kg of N ha −1 year −1 . Swards were cut to a height of 40 mm five times annually and mulched to the same height. Mulching significantly affected the botanical composition of lawns, wherein a decrease in the portion of legumes (from 32% to 19.1%) was observed. The returned grass matter supported a significant increase in the grass component in the lawns (from 57.8% to 69.7% of total). When the clippings were returned, quality remained the same. Returned clippings had a positive impact on colour and increased the height of cut swards significantly. Application of nitrogen decreased the share of legumes, supported the grass component, statistically increased quality, improved colour, and increased sward height. The results show that returning grass clippings through mulching is beneficial. In any case, it is necessary to apply at least a basal amount of mineral fertilizer in order to preserve the quality of urban lawns over the long term.

Questions (1) When alpine vegetation is actively restored by seeding, how is vegetation cover influenced by seeding treatments and soil conditions? (2) How does the cover of species differ when they are seeded in a mixture and how is their response influenced by soil conditions? (3) Do individual species perform better or worse in a mixture than when sown separately? Location Hjerkinn, Dovrefjell, Norway. Methods In a factorial, randomized field experiment, we recorded the percentage cover of Festuca ovina, Luzula multiflora ssp. frigida, and Poa alpina seeded in four different soil types for three years after seeding. We seeded the three species separately and in a mixture in organic topsoil, peat soil, mineral fine soil and mineral coarse soil. We also recorded seedling emergence in a greenhouse experiment, using the same seeding treatments. Results In the field experiment, vegetation cover established fastest when F. ovina was sown in monoculture followed by the seed mixture. After three years, mean cover of F. ovina was 1.4 higher than mean P. alpina cover and more than three times higher than mean L. multiflora cover for single-species treatments, and four (P. alpina) and 15 (L. multiflora) times higher when the species were seeded together. L. multiflora germinated slowly in the greenhouse experiment, which could partly explain its poor field performance. In the field experiment, establishment was faster in organic soils than mineral soils for all seeding treatments. The largest difference between F. ovina and L. multiflora performance in the mixture treatment was found in the organic soil types, where overall cover was larger than in the mineral soils. In the organic soils, F. ovina was slightly facilitated in the mixture treatment, while the opposite was found for L. multiflora. Conclusion When the restoration goal is to quickly establish a vegetation cover, seeding monocultures of rapidly establishing species may be more effective than seeding mixtures even in alpine sites where interspecific facilitation may prevail. This article is protected by copyright. All rights reserved.

Establishing perennial plant communities on roadsides is a proactive approach to sustainable road management. The environmental and economic benefits of increasing desirable roadside vegetation include improving slope stabilization, soil conservation, and roadway safety while reducing erosion, maintenance costs, and invasive plants. This study evaluated the success of roadside revegetation on 16 sites in Idaho and on one site in adjacent southwest Montana. Study sites represent a diversity of climatic, topographic, and edaphic conditions in order to provide a variety of examples of roadside revegetation projects in 6 different ecoregions of Idaho. We measured all species’ canopy cover, including noxious weeds and other invasive plants. Of the seeded grass species, 21 of 27 established. Bluebunch wheatgrass ( Pseudoroegneria spicata (Pursh)A. Love [Poaceae]) and Idaho fescue ( Festuca idahoensis Elmer [Poaceae]) were the best-performing native grasses. Seeded grass species that consistently established but had a low mean canopy cover (2–5%) included sheep fescue ( Festuca ovina L.), western wheatgrass ( Pascopyrum smithii (Rydb.) A. Love [Poaceae]), and basin wildrye ( Leymus cinereus (Scribn. & Merr.) A. Love [Poaceae]). Seeded forbs and shrub species had low establishment success and low mean percent canopy cover. For example, no seeded forb species had more than 1% mean canopy cover and greater than 50% establishment when present in the seed mix. Seed mixes of 10 or fewer species resulted in ≥ 50% of the species establishing. Idaho noxious weeds were present in less than half of the sites (47%). Cheatgrass ( Bromus tectorum L. [Poaceae]), an invasive annual grass, occurred in 82% of the sites. These results provide species selection recommendations based on ecoregion for use in roadside revegetation projects in Idaho and portions of western Montana.

Phosphogypsum (PG) is a by-product of phosphate fertilizer production. This study is the first to investigate Bromis inermis and Festuca ovina root morphology and colonization with arbuscular mycorrhizal fungi and dark septate endophytes (DSE) in pure PG and PG with a soil cap (soil). Root length density was significantly lower for plants on PG than on soil and both plant species were colonized with AMF and DSE, with lower frequency and intensity in PG. Phosphorus (20 times), calcium (35 times) and sulphur (50 times) were significantly higher in PG than in soil; resulting higher root tissue concentrations were significantly negatively correlated with mycorrhizal colonization for Festuca but not Bromus. Higher fungal colonization of Bromus, especially with DSE known to be prevalent in extreme environments, may be responsible for its better performance on PG relative to Festuca.

In the Mediterranean region, endozoochorous seed dispersal is a potential alternative for the recovery of degraded or abandoned grasslands and shrublands. The objectives of this study were to quantify the number of seeds that pass through the goat gut and to determine whether this process affects seed germination in six common herbaceous species of the Mediterranean area ( Ornithopus compressus L., Biserrula pelecinus L., Medicago polymorpha L., Melilotus officinalis L. Pall, Festuca ovina L. and Dactylis glomerata L). We also examined whether the inclusion of the seeds in dung affected seed germination and seedling establishment and growth. The highest seed recovery rate was obtained 24–72 h after ingestion. The amount of retrieved seeds varied among species and was generally low, with significant differences among some leguminous and grass species. With the exception of M. officinalis , the quantity of retrieved legume seeds (1.5–6.8%) was greater than that of the grass seeds (0.9–1.1%). A significant relationship was found between recovery of the seeds and their hardness and volume. In all species, the recovered seeds presented significantly lower germinability than seeds that had not been consumed. In general, all recovered legume seeds showed higher average germination rate values (18–50%) compared to recovered grass seeds (0–14%). Seedling emergence was lower in intact than in crumbled dung pellets and, in most cases, the values of both of these were lower than that of unconsumed (control) seeds. No seedling emergence was recorded for seeds of B. pelecinus and O. compressus contained in intact or crumbled faeces at all sampling times. While the percentages of recovery and subsequent emergence found in this study are low in absolute terms, we can conclude that a significant number of seeds may become established from the dung and could be a potential alternative for the recovery of degraded or abandoned grazing areas.

Roadside turfgrass mixtures are subject to a wide variety of extreme stresses including heat, drought, low nutrient availability, ice cover, and road salt exposure. The currently specified turfgrass seed mixtures for roadsides in Minnesota have not been based on the results of recent, designed experiments. A quantitative approach to evaluating turfgrass species mixtures for roadsides in Minnesota is needed in order to improve the current mixture recommendation. The objectives of this experiment were to (1) assess the performance of several mixtures of cool-season turfgrass for survival on roadsides in central Minnesota, (2) quantitatively evaluate the influence of individual species on the survival of turfgrass mixtures on roadsides, and (3) identify a suitable mixture of cool-season turfgrass species for roadsides in central Minnesota. In fall 2011, three replications of 51 cool-season turfgrass mixtures, comprising nine species of turfgrass, were established at two roadside locations in the metropolitan area surrounding St. Paul, MN, USA. Survival of the established mixtures was assessed using digital image analysis to determine percent living ground cover during both spring and summer 2012, and again using a grid-intersect method during spring 2013. Several mixtures were identified that performed significantly better than the current specified mix during spring or summer 2012. The log-odds of a plot retaining at least 60% living turfgrass cover in spring 2013 decreased by 1.78 for mixtures including tall fescue ( Festuca arundinacea L.). Hard fescue [ Festuca trachyphylla (Hack.) Krajina] and sheep fescue ( Festuca ovina L.) increased the log-odds of success by 0.95 and 0.96, respectively, and both estimates were significant at the 90% confidence level. Quantitative analysis of survival percentage in spring 2013 indicated that the best mixture for roadsides in central Minnesota comprises 20% slender creeping red fescue, 40% hard fescue, and 40% sheep fescue. These results can be used by public works officials to implement and improve roadside turfgrass mixtures in Minnesota.

Native grasses are important for the enhancement of landscape. Agropyron cristatum, A.intermedium, Festuca ovina, Festuca arundinaceae, Cynodon dactylon, Bromus inermis and B. confinis are the potential sources of low maintenance turfgrasses for semi-arid regions. This greenhouse study examined the interaction of four different levels of soil water contents with 75, 50, and 25% field capacity (FC) and non-irrigation on physiological and biochemical responses of each accession. Total carbohydrate and sucrose contents of F. arundinaceae were increased significantly under non-irrigated treatment but decreased in the other genotypes. Proline, hydrogen peroxide, and total ascorbate increased in all the species under drought. Also, with decreased soil water content, H2O2 content increased up to 50% in F. arundinaceae. Protein content of F. arundinacea increased significantly under drought stress compared to the control; however, it decreased in other genotypes. Ascorbate peroxidase activities were increased in Festuca sp. and decreased in A. cristatum. It was found that F. arundinacea was able to maintain higher relative water content level and osmotic potential in non-irrigated drought treatment than B. inermis and A. cristatum. It may be speculated that the observed drought stress tolerance was associated with the ability of accumulating compatible solutes and H2O2 signaling cascade. Also, the high activity of ascorbate peroxidase resulted in protection against oxidative damage. It seems that this mechanism worked better in F. arundinacea to be used as low maintenance turfgrass.

Spoil heaps are the visible footprint of hydropower production, particularly in vulnerable alpine environments. Speeding up vegetation development by seeding commercial grass species has been a common restoration practice for the last 50 years, but we lack information on whether seeded species decline and allow native plant cover to develop. We visually estimated cover of native vascular plants and five seeded grass species (Agrostis capillaris, Festuca ovina, Festuca rubra, Schedonorus pratensis and Phleum pratense) on eight spoil heaps at different elevations (boreal-alpine zone) in western Norway. Spoil heap vegetation was censused twice (9-20 and 24-36 years after spoil heap construction); the undisturbed surrounding vegetation was also censused on the second occasion. Total cover on the spoil heaps showed some increase, but remained far below that in surrounding areas. Cover of seeded grass species in the surroundings was low (but not negligible), indicating suboptimal establishment ability. Seeded species usually covered less than 20 % of the spoil heaps, and only F. rubra, F. ovina and A. capillaris contributed substantially. Proportional cover indicated better initial establishment by seeded species, but their cover decreased between the censuses on all but the highest located spoil heap. The persistence of seeded grass species is problematic, and despite the decrease in proportional cover, they are likely to persist for decades on spoil heaps, posing a risk of invasion of surrounding areas. We therefore recommend replacing the practice of seeding with more appropriate restoration measures.

Tolerance of four cool-season turfgrass species sheep fescue (Festuca ovina), perennial ryegrass (Lolium perenne), colonial bentgrass (Agrostis tenuis) and rough bluegrass (Poa trivialis) to SO2 was studied by investigating their injury and physiological responses under SO2 stress for 14 days. Results showed that sheep fescue and perennial ryegrass had better SO2 tolerance than rough bluegrass and colonial bentgrass. Chlorophyll a and carotenoid contents were significantly higher in the SO2-tolerant turfgrass species (sheep fescue and perennial ryegrass) than in the SO2-sensitive turfgrass species (rough bluegrass and colonial bentgrass). Relatively lower levels of reactive oxygen species (ROS), malondialdehyde, and electrolyte leakage (EL) were observed in SO2-tolerant turfgrass species. Gradually increased antioxidant enzyme activities and proline content in SO2-tolerant turfgrass species could counteract such damages and harmful effects caused by ROS and EL, respectively. Sulfite reductase played an im...

The optimal provision of green roof services is largely dependent on the health of the vegetation on the green roof, which is often affected by water availability.We assessed the impact of two substrate components, brick particle size and a polyacrylamide gel additive, and a living mulch (companion planting of Sedum spp.) on the growth, physiological and visual health of newly established plugs of Festuca ovina and Linaria vulgaris during an extreme drought (25 days) in a controlled environment greenhouse. Polyacrylamide gel and large brick substrates increased both plant species' drought tolerance whilst a Sedum living mulch had no effect. Polyacrylamide gel increased the reservoir of water that plants could access during the drought, whilst large brick promoted slower and therefore more drought resistant plant growth. Overall this study shows that polyacrylamide gel and coarser particle size substrates can significantly improve the drought tolerance of green roof plants.

We have measured the rates of root production and death and of root respiration in situ under two grasslands along an altitudinal gradient in the northern Pennines, UK, represented by a lowland site at 171 m in an agricultural setting, and three upland sites between 480 and 845 m. One grassland was dominated by Festuca ovina and was on a brown earth soil; the other was dominated by Juncus squarrosus and Nardus stricta and occurred on a peaty gley. The natural altitudinal gradient was extended by transplantation. Although root biomass and root production (estimated using minirhizotrons) both showed pronounced seasonal peaks, there was no simple altitudinal gradient in either variable, and neither root production nor root death rate was a simple function of altitude. Increased root accumulation in summer was a function of change in the length of the growing season, not of soil temperature. Root populations in winter were similar at all sites, showing that increased production at some sites was accompanied by increased turnover, a conclusion confirmed by cohort analyses. Respiration rate, measured in the field by extracting roots and measuring respiration at field temperature in an incubator, was unrelated to temperature. The temperature sensitivity of respiration (expressed as the slope of a plot of log respiration rate against temperature) showed no simple seasonal or altitudinal pattern. Both root growth (under Festuca) and respiration rate were, however, closely related to radiation fluxes, averaged over the previous 10 days for growth and 2 days for respiration. The temperature sensitivity of respiration was a function of soil temperature at the time of measurement. These results show that root growth and the consequent input of carbon to soil in these communities is controlled by radiation flux not temperature, and that plants growing in these upland environments may acclimate strongly to low temperatures. Most carbon cycle models assume that carbon fluxes to soil are powerfully influenced by temperature, but that assumption is based largely on short-term studies and must be reassessed.

We used outdoor microcosms in order to freely manipulate three trophic levels (ladybird/aphid/grass) at two soil fertility levels (low and high). Two hypotheses were tested: (1) that top-down control is only a mechanistic factor at high soil fertility, and (2) that herbivory increases secondary plant succession by preferentially feeding on the fast-growing early-successional grasses. Plant biomass responded dramatically to the high soil fertility treatment, as did aphid numbers in the absence of ladybirds, and ladybird activity (ladybirds feeding on aphids). At low soil fertility, plant biomass was low, aphid numbers were small, and ladybird activity was minimal. Only at high soil fertility did top-down control cause a significant response to plant biomass and species composition. The two fast-growing, early-successional grasses (Poa annua and Arrhenatherum elatius) had a greater biomass in the presence of the ladybirds compared to when the ladybirds were absent, while the slow-growing, late-successional grass (Festuca ovina) suffered. The opposite was found when ladybirds were absent but aphids present. These results suggest that herbivory may increase the rate of secondary succession, but that top-down control of herbivory by carnivores may reduce the impact of herbivory in high productivity communities.

tAnthropogenic deposition of reactive nitrogen (N) has increased during the 20th century, and is con-sidered an important driver of shifts in ecosystem functions and biodiversity loss. The objective of thepresent study was to identify those ecosystem functions that best evidence a target ecosystem’s sensitiv-ity to N deposition, taking coastal heathlands as an example. We conducted a three-year field experimentin heathlands of the island Fehmarn (Baltic Sea, North Germany), which currently are subject to a back-ground deposition of 9 kg N ha−1yr−1. We experimentally applied six levels of N fertilisation (applicationof 0, 2.5, 5, 10, 20, and 50 kg N ha−1yr−1), and quantified the growth responses of different plant speciesof different life forms (dwarf shrubs, graminoids, bryophytes, lichens) as well as shifts in the C:N ratios ofplant tissue and humus horizons. For an applicability of the experimental findings (in terms of heathlandmanagement and critical load assessment) fertilisation effects on response variables were visualised bycalculating the treatment ‘effect sizes’. The current year’s shoot increment of the dominant dwarf shrubCalluna vulgaris proved to be the most sensitive indicator to N fertilisation. Shoot increment significantlyresponded to additions of ≥ 5 kg N ha−1yr−1already in the first year, whereas flower formation of Callunavulgaris increased only in the high-N treatments. Similarly, tissue C:N ratios of vascular plants (Callunavulgaris and the graminoids Carex arenaria and Festuca ovina agg.) only decreased in the highest N treat-ments (50 and 20 kg N ha−1yr−1, respectively). In contrast, tissue C:N ratios of cryptogams respondedmore quickly and sensitively than vascular plants. For example, Cladonia spp. tissue C:N ratios respondedto N additions ≥ 5 kg N ha−1yr−1in the second study year. After three years we observed an increase incover of graminoids and a corresponding decrease of cryptogams at N fertilisation rates of ≥ 10 kg N ha−1yr−1. Soil C:N ratios proved to be an inappropriate indicator for N fertilisation at least within our three-year study period. Although current critical N loads for heathlands (10−20 kg N ha−1yr−1) were confirmedin our experiment, the immediate and highly sensitive response of the current year’s shoots of Callunavulgaris suggests that at least some ecosystem functions (e.g. dwarf shrub growth) also might respond tolow (i.e. < 10 kg N ha−1yr−1) but chronic inputs of N. Anthropogenic deposition of reactive nitrogen (N) has increased during the 20th century, and is considered an important driver of shifts in ecosystem functions and biodiversity loss. The objective of the present study was to identify those ecosystem functions that best evidence a target ecosystem’s sensitivity to N deposition, taking coastal heathlands as an example. We conducted a three-year field experiment in heathlands of the island Fehmarn (Baltic Sea, North Germany), which currently are subject to a background deposition of 9 kg N ha−1 yr−1. We experimentally applied six levels of N fertilisation (application of 0, 2.5, 5, 10, 20, and 50 kg N ha−1 yr−1), and quantified the growth responses of different plant species of different life forms (dwarf shrubs, graminoids, bryophytes, lichens) as well as shifts in the C:N ratios of plant tissue and humus horizons. For an applicability of the experimental findings (in terms of heathland management and critical load assessment) fertilisation effects on response variables were visualised by calculating the treatment ‘effect sizes’. The current year’s shoot increment of the dominant dwarf shrub Calluna vulgaris proved to be the most sensitive indicator to N fertilisation. Shoot increment significantly responded to additions of ≥ 5 kg N ha−1 yr−1 already in the first year, whereas flower formation of Calluna vulgaris increased only in the high-N treatments. Similarly, tissue C:N ratios of vascular plants (Calluna vulgaris and the graminoids Carex arenaria and Festuca ovina agg.) only decreased in the highest N treatments (50 and 20 kg N ha−1 yr−1, respectively). In contrast, tissue C:N ratios of cryptogams responded more quickly and sensitively than vascular plants. For example, Cladonia spp. tissue C:N ratios responded to N additions ≥ 5 kg N ha−1 yr−1 in the second study year. After three years we observed an increase in cover of graminoids and a corresponding decrease of cryptogams at N fertilisation rates of ≥ 10 kg N ha−1 yr−1. Soil C:N ratios proved to be an inappropriate indicator for N fertilisation at least within our three-year study period. Although current critical N loads for heathlands (10−20 kg N ha−1 yr−1) were confirmed in our experiment, the immediate and highly sensitive response of the current year’s shoots of Calluna vulgaris suggests that at least some ecosystem functions (e.g. dwarf shrub growth) also might respond to low (i.e. < 10 kg N ha−1 yr−1) but chronic inputs of N.

Complete vineyard floor cover crops were evaluated in a long-term study for their ability to regulate excessive vegetative growth of the grapevine (Vitis vinifera L.) variety ‘Cabernet Sauvignon’. Treatments were: tall fescue (Festuca arundinacea Shreb.) ‘KY-31′ and ‘Elite II’, hard fescue (Festuca ovina L.) ‘Aurora Gold’, perennial ryegrass (Lolium perenne L.), orchardgrass (Dactylis glomerata L.), and an under-trellis herbicide strip combined with KY-31 fescue interrows. Compared to herbicide-treated soil strip, Elite II fescue reduced vine pruning weights (kg/vine) 28%, individual cane weight (g) 20%, and canopy leaf layer number 25%. KY-31 fescue produced the greatest biomass and stand density, while perennial ryegrass produced the least biomass and Aurora Gold hard fescue produced the lowest stand density. Elite II fescue produced less biomass but equivalent stand density compared to KY-31 fescue. Treatments minimally impacted vine water potential (Ψmd, Ψstem), indicating that the grasses were not overly competitive with grapevines for soil moisture. All grass treatments tended to depress grapevine nitrogen levels relative to the under-trellis herbicide strip treatment, but no treatment resulted in vine nitrogen levels below the acceptable sufficiency range. Because of its establishment and growth characteristics, desired suppression of vine vegetative growth, and its low impact on crop yield, we considered Elite II fescue the optimal cover crop evaluated.

The most frequent way to establish turfgrass in the climatic conditions of the Czech Republic is sowing during spring period. The seedlings are endangered by lack of soil moisture and by high temperatures if irrigation is no available. One of the possibilities how to increase probability of successful turfgrass establishment in warm areas which suffer by low amount of precipitation is autumn term of sowing. Eight grass species and subspecies and two legumes were sown in three autumn terms (September, October and November) during 2009 and 2010. The shortest time for seedling emergence was found in average of all terms at Medicago lupulina and Trifolium repens (9 days). Lolium perenne (14) and Festuca arundinacea (17) were the fastest emerged grasses. On the other hand the longest emergence time was realised at Poa pratensis (23), Festuca rubra ssp. trichophyla (22) and Festuca ovina (21). Plants sown in September emerged in 10 days, in October 12 and in November in 29 days. September term was suitable for all used species but November term underwent most successfully Festuca rubra ssp. commutata (23% soil cover in April next year) and Lolium perenne (19%). November term was not acceptable for legumes.

Seed germination, seedling development, and vegetative growth of nine fine fescues cultivars [‘Slender’ creeping red fescue ( Festuca rubra L. ssp. rubra and Festuca rubra L. ssp. trichophylla Gaud.), ‘Firefly’ and ‘Reliant IV’ hard fescue ( Festuca longifolia Thuill.), ‘Azure’ and ‘Marco Polo’ sheep fescue ( Festuca ovina L.), and ‘Intrigue’, ‘Columbia II’, ‘Ambrose’, and ‘Jamestown II’ chewing fescue ( Festuca rubra L. ssp. commutata Gaud.)] were determined under saline conditions (NaCl at 0, 3, 6, 9, and 12 g L −1 ) and compared to ‘Zoom’ perennial ryegrass ( Lolium perenne L.), ‘Stonewall’ tall fescue ( Festuca arundinacea Schreb.), and ‘Bewitched’ Kentucky bluegrass ( Poa pratensis L.). Salinity reduced final and daily germination rate. Similarly, seedling development (fresh weight, dry weight, and absolute water content) and vegetative growth (shoot and root dry weight and the longest root length) declined with increasing salinity levels. Daily germination rate, fresh weight and absolute water content, and root dry weight and the longest root length are more sensitive to salinity compared to other parameters during initial (germination and seedling development) and vegetative growth stages respectively; therefore, better indicators of salt tolerance. All fine fescue cultivars showed a constant ranking of relative salt tolerance at different growth stages. Overall, ‘Zoom’ perennial ryegrass, ‘Slender’ creeping red fescue, and ‘Stonewall’ tall fescue exhibited the most tolerance to high salt concentrations. However, limited variations existed in salinity tolerance among ‘Bewitched’ Kentucky bluegrass and the other fine fescue cultivars.

IntroductionGrass species may acquire different forms of nitrogen (N) to reduce competition for the same resources. Climate change influences the availability of soil N and is therefore likely to cause shifts in N forms acquired by plants, thereby affecting their competitive interactions.MethodsWe investigated the effects of warming on the uptake of different N forms and competitive interactions of Festuca ovina and Anthoxanthum odoratum in a pot experiment. The plants were grown either in monocultures or mixture, and at ambient or elevated temperature (+10 °C), and supplied with 13C and 15N isotopes to test for treatment effects on the relative uptake of ammonium, alanine or tri-alanine.ResultsBoth grass species took up relatively more N supplied as ammonium than as alanine or tri-alanine when grown under ambient conditions in monoculture. In contrast, when grown in mixtures, F. ovina took up the three supplied N forms in equal amounts, whereas A. odoratum switched to tri-alanine as the main N form. Under warmed conditions, both species took up the N forms equally, irrespective of competition treatments.ConclusionsWe have shown that grass species grown in mixture and under ambient conditions reduce competition by acquiring different N forms. Warming increased the availability of inorganic N in the soil and therefore deregulated the need for differential uptake of N forms.KeywordsAmino acid Peptide Nutrient Coexistence Niche differentiation

The harsh and stressful growing environment of extensive green roofs especially in arid environments allows a limited range of plant species to survive. Therefore, achieving plantings to survive in such conditions is a significant challenge. This paper describes an experiment investigating plant selections for extensive green roofs based on chilling (cold season) and drought (warm season) conditions of Iran. Nine species were selected from the three major taxonomic and functional plant groups that are commonly used on extensive green roofs including grasses, groundcovers and sedums. The species namely Agropyron cristatum, Festuca aurundinacea, Festuca ovina, Potentila sp., Frankinia thymifolia, Vinca minor, Sedum acre, Sedum spurinum, Carpobrotus edulis were imposed to natural chilling in autumn and winter using a randomized complete block design. For spring and summer, irrigation regimes at levels (48, 72 and 96 h intervals) in a factorial experiment based on a randomized complete block design with four replications were applied. The results showed that Agropyron cristatum, Frankinia thymifolia and Carpobrotus edulis were the best plants from each class. Carpobrotus edulis was the best choice for cold and warm seasons and this was followed by Frankinia thymifolia and Potentila sp. Vinca minor performed well in the cold seasons and Sedum spurinum appeared to be excellent in the warm seasons. The plants of the experiment showed significantly different appearances in different watering regimes. Little differences in drought tolerances were observed among the forbs and grasses, which must be watered during warm seasons. However, the succulents responded very well to the drought and low watering regimes. Overall, succulents and groundcovers were considered more appropriate for application in warm and cold seasons, respectively. According to the findings, drought and cold weather conditions cannot be a major obstacle for developing extensive green roofs in Iran if considerations are made on selecting its plant species.

Silica defences in grasses have recently been suggested to be a potential driver of vole population dynamics. However, the ability of grasses to induce silica in response to herbivory has not been tested in northern ecosystems where small rodents are important herbivores. We conducted a large-scale field experiment in subarctic tundra using three river catchments differing in herbivore densities, and examined the effects of small rodent and/or reindeer exclusion on leaf silica levels in five grass species (Avenella flexuosa, Anthoxanthum nipponicum, Calamagrostis phragmitoides, Deschampsia cespitosa and Phleum alpinum). We also conducted a greenhouse experiment using three of these species (A. flexuosa, A. nipponicum and D. cespitosa) and Festuca ovina to determine whether intraspecific genotypic variation affects baseline silica concentrations and the capacity to induce silica in response to simulated grazing. Baseline leaf silica concentrations and silica induction varied with plant species in both experiments, with catchment in the field experiment and with genotype in the greenhouse experiment. These findings show that the allocation to silica defences in grasses is highly variable, and suggest that the combined effects of grazing pressure, plant species and intraspecific genotypic differences are likely to determine the circumstances under which silica induction may be an optimal defence strategy. A better understanding of the interplay between grazing and other factors influencing silica induction is necessary to interpret the role of silica in plant–herbivore interactions.

This study focuses on the identification of ignition characteristics and carbon discharge resulting from combustion of surface fuels vulnerable to forest fire. Four withered surface fuels, including dead leaves and cones of Pinus densiflora, dead leaves of Quercus variabilis, and Castenea crenata burs; and six biofuel herbs, including Agsstache rugosa, Oplismenus undulatifolius, Pueraria thunbergiana, Cirsium japonicum var. ussuriense, Festuca ovina L., and Osmundaceae were selected for analysis. Also, monthly carbon emissions (Jun. - Oct. 2008) from Festuca ovina were analyzed. As a result of tests, it was confirmed that dead leaves and cones of P. densiflora and C. crenata burs were instantly ignited with flame, which lasted quite a while. The total CO2 and CO emissions from the 10 different kinds of surface fuels analyzed on this study were 28-98 g and 0.76-4.08 g per 50 g of each fuel, respectively, indicating that the amount of carbon emissions vary depending on the type of fuel. The results also demonstrated that there is a great difference between withered fuels and biofuels in terms of carbon emissions. More specifically, the four withered types of fuels, compared to the six biofuel herbs, were found to emit more CO2 and CO. In particular, dead cones of P. densiflora emitted more carbon dioxide (CO2) and carbon monoxide (CO) than the rest of the surface fuels. Also, the carbon emissions were found high during the period of from August to September. Consequently, in the case of a forest fire, dead cones and leaves of P. densiflora are expected to emit up to 3.5 times more CO2 and CO than the other surface fuels. The area covered with dead leaves and pine cones is thought to have a high risk of ignition, high fire inten- sity because of relatively long lasting flame, and rapid fire spread. Herbs and living fuels with high moisture content are expected to elucidate the course of fire in that they produce large amount of combustion prod- ucts such as smoke and carbon discharge resulting from nonflame-ignition.

A field replacement experiment was used to study the interspecific interaction among three perennial grasses (Elymus nutans, Festuca sinensis and Festuca ovina) that are distributed widely on the east Qinghai-Tibetan plateau. The experiment consisted of four different species mixtures at four seeding densities and two fertilizer levels. Above-ground biomass, relative yield and complementary effect were determined from harvested shoot dry weights. The results showed that above-ground biomass was greater in all species mixtures than in monocultures. The difference between the observed and expected relative yield was greater than zero in all mixtures for E. nutans and was greater than zero in the F. sinensis/F. ovina mixture, but was below zero in all other mixtures for F. sinensis, and was below zero in all mixtures for F. ovina. The complementary effect was more negative across all seeding densities except at a seeding density of 400 seeds/m2, and was negative across all mixtures except the F. sinensis/F. ovina mixture. In addition, fertilization had an insignificant impact on the relative yield, but a significant impact on the complementary effect. Fertilization enhanced negative interspecific interaction among the species.

The importance of rotational fallows for pollinating insects in intensively cultivated farmland was studied in a three-year field experiment. The focus was on the establishment method (undersowing or seed mixture sown post-tillage), seed mixture (competitive Festuca pratensis – Phleum pratense – Trifolium pratense or less competitive Agrostis capillaris – Festuca ovina mixture) and duration (1 or 2 years) of the fallow. The seed mixture and duration affected the pollinators more than the method of establishment. Pollinator species richness was higher in fallows sown with less competitive than with competitive grasses and it increased in the second year. Stubble fields reached as high pollinator species richness already during the first year as fallows with less competitive grasses did in the second year. Pollinator abundance was highest in those treatments in which species richness of flowering plants was highest. The results suggest that the benefits of rotational fallows for pollinators increase when they are established as stubble or using seeds of less competitive grasses and when the field is fallowed for (at least) two summers.

In order to study the combined effect of nitrogen and glyphosate on biodiversity in agricultural areas, a replicated long-time field experiment with glyphosate and nitrogen treated plots was set-up. The experiment allowed a quantitative estimation of the effect of glyphosate and nitrogen on competitive growth, survival and establishment of the dominating species during and between growing seasons. It was found that the observed ecological success of Festuca ovina relative to Agrostis capillaris in glyphosate treated plots was primarily due to altered competitive plant growth during the growing season rather than an immediate die back following spraying. Overall, interaction of herbicide and fertilizer on plant competitive growth, survival and establishment were demonstrated, and it was suggested that positive interactions between glyphosate and nitrogen may be important for the ecological success of A. capillaris in field margins. The used method of combining pin-point data and Bayesian state-space competition models may be applied in other ecological studies. For example, the method may be used in predicting the effects of altered weed control strategies on the botanical composition of the agro-ecosystem.

Phosphogypsum (PG), a byproduct of phosphate fertilizer manufacturing, is commonly stacked and capped with soil at decommissioning. Shallow (0, 8, 15, and 30 cm) and thick (46 and 91 cm) sandy loam caps on a PG stack near Fort Saskatchewan, Alberta, Canada, were studied in relation to vegetation establishment and hydrologic properties. Plant response was evaluated over two growing seasons for redtop (Agrostis stolonifera L.), slender wheatgrass (Agropyron trachycaulum (Link) Malte ex H.F. Lewis), tufted hairgrass (Deschampsia caespitosa (L.) P. Beauv.), and sheep fescue (Festuca ovina L.) and for a mix of these grasses with alsike clover (Trifolium hybridum L.). Water content below the soil–PG interface was monitored with time-domain reflectometry probes, and leachate water quantity and quality at a depth of 30 cm was measured using lysimeters. Vegetation responded positively to all cap depths relative to bare PG, with few significant differences among cap depths. Slender wheatgrass performed best, and tufted hairgrass performed poorly. Soil caps

The effects of pipeline construction and reclamation techniques on the restoration of rough fescue plant communities following pipeline construction in southwestern Alberta, Canada were evaluated after 7-40 years. The pipeline construction right-of-way (ROW) sites varied from no recovery of rough fescue grassland to moderate recovery. The ROW sites had a higher proportion of introduced grasses and forbs, less topsoil, and poorer rangeland health than the adjacent undisturbed grassland. Within the ROW sites, less topsoil was present on those with larger diameter pipe and which had topsoil fully stripped from the ROW during construction. Introduced grasses, Festuca ovina (sheep fescue) and Poa compressa (Canada bluegrass), succeeded in establishment following seeding and persisted for at least 40 years. Poa pratensis (Kentucky bluegrass) dominated many of the ROW sites. Contributing factors to moderate recovery of rough fescue grassland were related to post-growing season pipeline construction, ideally, between August and March, summer or fall seeding, and minimum disturbance trench-only stripping. Reclamation practices appeared more important than time since restoration in the restoration of rough fescue grassland.

The objective of this experiment was to investigate the influence of intercropping with three different perennial grass species (Festuca ovina L., Festuca rubra subsp. tricophylla L. and Poa nemoralis L.) on the Fe nutritional status of citrumelo 'Swingle' (Citrus paradisi Macf. × Poncirus trifoliata), a highly Fe chlorosis susceptible citrus rootstock. One-year old citrumelo plants were grown in pots on calcareous soil-sand mixture under greenhouse conditions and treated as follows: 1) citrumelo plants grown in a monoculture system (without a companion crop); 2) citrumelo plants fertilized with 18.6 mg Fe per plant in form of FeEDDHA; 3) citrumelo plants separately intercropped with the three perennial grass species. These grasses were sown at a rate of 3 seeds cm -2 , mowed only one time and allowed to re-grow. The experiment lasted five months. Chlorophyll measurements were performed on the youngest fully expanded leaves in terms of SPAD index and at the end of the experiment leaf chlorophyll content (μg cm -2 ), leaf length and width and dry weight of young shoots were determined. Intercropping citrumelo plants with F. rubra was effective almost as FeEDDHA in preventing the development of leaf chlorosis and improving their growth compared to the control plants, while those intercropped with F. ovina overcame Fe deficiency symptoms only after mowing/clipping this grass species. The Poa nemoralis did not demonstrate any potential to prevent leaf chlorosis or improve the growth of citrumelo plants. These results indicate that only Fe-efficient perennial grass species can be utilized as an effective ecological orchard floor management practice to improve the Fe nutrition of fruit trees grown on calcareous soils.

Use of composts for habitat restoration offers advantages in terms of efficient use of resources. Chemical amendment of compost to reduce its pH and P availability was investigated in order to improve suitability for use in reclamation of blocky quarry waste to acidic grassy heathland. The effect of these amendments was observed on competition between two grass species: Agrostis capillaris and Festuca ovina. A factorial, pot-scale greenhouse experiment was set up using two composts (one a mixture of green waste and catering waste, and the other a mixture of green waste and sewage sludge). In addition, two soils were collected from upland acidic grassland to provide a natural comparison. S0 was applied to reduce soil pH, and Fe(OH)3 from a coal waste treatment plant was applied to counteract the expected increase in P availability due to acidification of the composts by S0. Addition of S0 significantly reduced soil solution pH and addition of Fe(OH)3 significantly reduced soil solution P concentration. In one compost S0 reduced the biomass of F. ovina while increasing that of A. capillaris, whereas Fe(OH)3 had no significant effect on the biomass of either species. Although S0 and Fe(OH)3 did adjust the chemical properties of the soil solution, Fe(OH)3 did not bind P strongly enough to make it unavailable to plants. Further work is required, however, the use of chemically amended composts provides a sustainable sink for organic wastes and we conclude from this study that they have great potential for large-scale restoration of blocky waste tips.

A field experiment was conducted at New Mexico State University to investigate the effect of seeding rates and ZEBA polymer [starch-g-poly (2-propenamide-co-propenoic acid) potassium salt] seed coating on the germination and establishment of warm- and cool-season grasses, and cool-season blends and mixtures. Grasses were established at recommended and reduced (50% of recommended) seeding rates with coated and uncoated seeds under two irrigation regimes (98% and 56% reference evapotranspiration). With the exception of ‘Bengal’ creeping bentgrass (Agrostis stolonifera), the polymer coating did not improve germination of the turfgrasses tested 22 days after seeding (DAS). However, at the end of the establishment period (92 DAS), plots established with ‘Bengal’, Dunes Mix [mixture of ‘Hardtop’ hard fescue (Festuca longifolia), ‘Baron’ kentucky bluegrass (Poa pratensis), ‘Barok’ sheep fescue (Festuca ovina)], ‘Panama’ bermudagrass (Cynodon dactylon), and Turf Sense™ [mixture of ‘Baronie’ kentucky bluegrass, ‘Barlennium’ perennial ryegrass (Lolium perenne), and ‘Barcampsia’ tufted hairgrass (Deschampsia cespitosa)] achieved greater coverage (based on visual estimations) when coated seed was used compared with uncoated seed. Establishment was greater for ‘Bengal’, Dunes Mix, ‘Panama’, Turf Sense™, and Turf Saver™ [blend of ‘Barlexas II’, ‘Barrington’, and ‘Labarinth’ tall fescue (Festuca arundinacea)] when normal seeding rates were applied compared with reduced seeding rates. ‘Barleria’ crested hairgrass (Koeleria macrantha) plots did not establish, regardless of the treatments applied. Results showed that seed coating has the potential to improve establishment at recommended and reduced seeding rates and can compensate for less favorable conditions such as reduced irrigation, reduced seeding rate, or for a combination of both. At the end of the establishment period, not all grasses achieved coverage greater than 50%. Further research over a longer establishment period is needed to determine if coated seed can be beneficial in achieving full coverage.

Grasses, which dominate many terrestrial ecosystems, sustain high densities of grazing mammals, so are of great economic and ecological importance. Traditionally, grasses are thought to be adapted to tolerate grazing rather than defend against it; however, silica deposited in the leaves of grasses has recently been shown to act as a feeding deterrent to invertebrate herbivores and small mammals. This study assesses whether silica is effective as a feeding deterrent to larger mammalian herbivores. We assess the impact of manipulated silica levels in five grass species on the feeding preferences of sheep both within and between grass species. Sheep feeding behaviour was driven by between-species differences in palatability. Hence, within a single species silica addition did not cause significant changes in feeding preference. However, there were significant differences in both the feeding preferences and bite rates between grass species, and these differences were much more marked when the grasses had been exposed to high levels of silica. The impacts that silica had on preference were least pronounced in palatable species (e.g. Poa annua) compared with less-palatable species (e.g. Brachypodium pinnatum and Festuca ovina). Sheep fed for longer, took more bites and had a higher bite rate on the grass species with the lowest leaf silica concentrations, namely P. annua. Sheep were less affected by silica defences than smaller, non-ruminant herbivores, but the changes in species preference rankings caused by silica suggest it may lead to changes in sward composition. Further, in species that are already relatively low in palatability, silica-induced reductions in bite rate could potentially reduce forage intake rates, with consequences for sheep performance.

We studied the effects of differences in root growth and nutrient pool on the competitive ability of Festuca ovina (short grass), Arrhenatherum elatius and Calamagrostis epigejos (tall grasses) grown in monocultures and in mixtures of homogeneous and heterogeneous environments during two growing seasons. Analysis of variance revealed a significant effect of plant species on nutrient concentrations in above-ground biomass and of substrate type on contents of N, K, Ca, Mg in biomass. The ANOVA also confirmed the significant effect of competitive environment on the concentration of N, K in above-ground biomass. In heterogeneous environments, both tall grasses (in competition with F. ovina) were able to produce more roots in the nutrient-rich patches and to accumulate more nitrogen in plant tissues, which was associated with higher yield of their above-ground biomass. Thus, the relative competitive ability for nutrients of both tall grasses was higher than that of F. ovina. This competitive ability of A. elatius to C. epigejos increased in heterogeneous treatments.