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Many livestock producers minimize input costs by relying solely on naturalized, mixed‐species pasture, but expose themselves to risks associated with forage yields that fluctuate in response to variable environmental conditions. This study was undertaken to assess winter triticale (×Triticosecalespp.) as a potential component of forage systems from the perspective of reducing forage yield risk. Triticale was sown each month from May until October in replicated plots for five consecutive years. Monthly harvests of triticale and mixed‐pasture plots were made through October during the year of establishment and in April and May the following spring. Monte Carlo simulation modeled differences between triticale and mixed pasture yields for each planting month and harvest month combination. The models predicted that triticale yields in August (June planted) and October (August planted) should exceed mixed pasture yields by averages of 0.62 ± 0.32 (mean ± standard deviation) and 0.77 ± 0.52 Mg ha−1, respectively. Yields of triticale planted in July or later and harvested in the following spring were also predicted to exceed mixed pasture by 0.50 ± 0.21 Mg ha−1for July planted/April harvest to 1.33 ± 0.32 Mg ha−1for September planted/April harvest. Risk analysis produced probabilities of benefit from incorporating triticale into forage systems, thus generating more meaningful results than conventional ANOVA.

The unequivocal success of ‘Grasslands Puna’ (Puna) chicory (Cichorium intybusL.) as a forage species in other areas has not been realized in the central Appalachian Region of the USA. A field study was conducted in southern West Virginia (38° N, 81° W; 850 m above sea level) to compare nutritional qualities and palatability of herbage from three forage chicory cultivars that were developed in different parts of the world. Puna, ‘INIA Le Lacerta’ (Lacerta), and ‘Forage Feast’ were established on a Gilpin soil (fine‐loamy, mixed, semiactive, mesic, Typic Hapludults) in replicated plots in 1997 and 1998, and herbage was used for chemical analyses and ruminant feeding assessments. Whitetail deer (Odocoileus virginianus), in a free‐foraging situation, and sheep (Ovis aries), in two cafeteria trials, discriminated against Forage Feast. Deer selected Lacerta first; sheep did not exhibit a preference for Lacerta over Puna. Mature leaves from vegetative rosettes of the three cultivars had similar concentrations of crude protein, neutral detergent fiber, and acid detergent fiber (P> 0.10). In vitro organic matter disappearance and amino acid composition were also similar among the cultivars (P> 0.05). In all cultivars, approximately 65% of the total N occurred as protein amino acids. Nonprotein amino acids were not major constituents in any of the cultivars. Results suggest that differences in palatability and intake of chicory are related to the secondary plant metabolite composition of the herbage.

Cool‐season forages dominate pastures in the Appalachian region where midsummer weather conditions often depress productivity. Warm‐season forages can buffer variation in available herbage, but land resources may limit the area dedicated to special‐use crops. A replicated field plot experiment was conducted for 3 yr (1995–1997) in a bermudagrass (Cynodon dactylonL.) stand oversown with Kentucky bluegrass (Poa pratensisL.) and white clover (Trifolium repensL.) to determine the influence of defoliation on productivity, nutritive value, and botanical dynamics of the mixture. Botanical composition changed with defoliation and varied among years. Bermudagrass comprised as much as 55% of the sward in mid‐ and late‐season 1995. By 1997, the proportion was similar to other grasses and rarely exceeded 20%. Maximum instantaneous growth rates occurred later in the growing season in 1995 when bermudagrass was a dominant sward component compared with subsequent years when bermudagrass was <10% of the sward. Rates in 1995 were greatest for swards clipped at 6‐wk intervals (70 kg ha−1d−1) or when 20‐cm tall and least when clipped at 2‐wk intervals (33 kg ha−1d−1) and at 10‐cm height (45 kg ha−1d−1). The trend was reversed by 1997 when sward composition shifted away from bermudagrass to cool‐season grasses and white clover. Yields were greatest when cool‐season species dominated the sward. Creating a self‐regulating mixture of warm‐ and cool‐season perennial forages may be a means of achieving some stability in sward productivity and might be useful where wide fluctuations in growing conditions occur among years.

Most studies on forage chicory (Cichorium intybusL.) are empirical, and very little information exists regarding the growth of chicory as it relates to development, productivity, persistence, and stand age. Development of uncut ‘Grasslands Puna’ chicory was studied in southern West Virginia on previously established plots at the Scott Farm in 1997 and 1998 and on 1‐yr‐old plantings at the Plumley Farm in 1998 and 1999. Chicory developmental parameters were modeled as a function of growing degree days (GDD) from Calendar Day 90 using a base of 5°C. On average, only 58% of the chicory plants became reproductive in any single growing season or location after the establishment year. Mean time to initiation of bolting and first open flower occurred consistently at approximately 400 and 1030 GDD, respectively, across locations and years. The indeterminate meristem of vegetative plants continuously produced leaves of relatively uniform mature area throughout the growing season. In comparison, the determinate meristem of reproductive plants rapidly expressed progressively smaller leaves on the main stem from initiation of bolting only until the time of first open flower. The developmental data herein create a framework with which to begin optimizing strategies for pasture and livestock grazing management of forage chicory.

Chicory (Cichorium intybusL.), a highly productive forage under midsummer conditions in the eastern USA, often has higher concentrations of minerals relative to grasses and legumes. Low concentrations of minerals in herbage could reduce production efficiency or create metabolic disorders in livestock. Information on the mineral composition of chicory is limited, but it is needed to improve our understanding of nutritive value and inputs required to sustain chicory production, especially where high rates of N are applied. We conducted field experiments for 3 yr on a Ramsey soil (Loamy, siliceous, subactive, mesic Lithic Dystrudept) in southern West Virginia to determine (i) response to increasing fertilizer N and (ii) production of chicory as a component of swards, including grass and legume as a function of clipping frequency. Mineral concentrations and uptake in available herbage generally increased as N rate increased and were influenced by the botanical composition of the sward. As chicory content decreased in the sward, so did mineral concentrations and uptake. Changes in sward composition associated with chicory influenced important mineral ratios such as N/S, Ca/P, and K/(Ca + Mg) cation equivalent ratio that have significant bearing on livestock health and production efficiency. Clipping frequency and N inputs influenced chicory persistence and ultimately the mineral composition of the sward. Active accumulation of minerals indicates the need for high nutrient input to sustain production, especially on soils with marginal fertility. Health problems associated with mineral nutrient concentrations probably would be minimal in livestock grazing swards that include chicory.

In modern forage systems, there is increased emphasis on use of nontraditional forages to supply nutrients to livestock. Field and laboratory experiments were conducted to evaluate the utility and nutritive value of chicory (Cichorium intybusL.; CHIC) as a component of hill‐land pastures in Appalachia. In 1995, lamb (Ovis aries) gain was 56.1 kg ha−1on orchardgrass (Dactylis glomerataL.; OG), while those grazing OG + CHIC lost 24.2 kg ha−1during the 44‐d midsummer grazing period (P< 0.05). In 1996, while weight gains were not different (P> 0.10), total lamb production per hectare was 14% less on OG + CHIC (258 kg ha−1) than on OG only (300 kg ha−1) for the 79‐d grazing period. In 1997, total weight gained for the season was not different (P> 0.10); lambs grazed OG or OG + CHIC for 110 d and production was 362 and 351 kg ha−1, respectively. Laboratory mixtures of 40:60 or 60:40 OG:CHIC had higher (P< 0.05) in vitro organic matter disappearance (IVOMD), compared with 100% OG or 100% CHIC. There was a synergism in mixtures with orchardgrass that increased IVOMD relative to pure samples. Another laboratory experiment suggested that as total N increased in chicory herbage, rate of in vitro neutral‐detergent fiber (NDF) disappearance decreased. More information on the influence of soil type and management on chicory growth in pure stands and mixtures with other plant species is needed to optimize productivity of systems that include chicory.

Pure stands of ‘Grasslands Puna’ chicory (Cichorium intybusL.) are productive and responsive to N fertilization in the eastern USA. We conducted a field experiment for 3 yr to investigate productivity and nutritive value of swards including chicory, orchardgrass (Dactylis glomerataL.), and birdsfoot trefoil (Lotus corniculatusL.) as a function of clipping frequency (3‐ and 6‐wk intervals). Each treatment was replicated three times on an upland site of Dekalb series soil (loamy‐skeletal, mixed, subactive, mesic Typic Dystrochrept). Modest rates of N, P, and K were applied annually. Herbage mass, botanical composition, in vitro organic matter disappearance (IVOMD), and crude protein (CP) were determined. Cumulative herbage yield was not influenced by initial sward composition with chicory, chicory‐orchardgrass, and chicory–orchardgrass–trefoil averaging 6.8 Mg ha−1during a growing season. Clipping frequency influenced yield with canopies clipped at 6‐wk intervals producing 26% more herbage than those clipped at 3‐wk intervals. Growth rates of canopies clipped at 6‐wk intervals averaged 51 kg ha−1d−1early in the growing season, suggesting that swards including chicory would be responsive to nutrient inputs and where rapid herbage regrowth and nutrient use by the growing crop are needed. Chicory declined in swards with time, regardless of initial sward composition or clipping frequency. Fluctuations in IVOMD and CP were related to changes in sward composition arising from the interaction of time and clipping frequency. Including orchardgrass and trefoil retarded invasion of less desirable species and so provided a means to control overall sward productivity and herbage composition.

Inadequate energy intake across the grazing season can be a major limitation to performance of grazing ruminants. A small‐plot experiment was conducted to determine the effect of repeated defoliation, based on canopy height and on the quantity and quality of tall fescue × perennial ryegrass (Festuca arundinaceaSchreb. × Lolium perenneL.) hybrid, orchardgrass (Dactylis glomerataL.), and prairie grass (Bromus catharticusM. Vahl) in the Central Appalachian Region of the USA. Energy determined from herbage quality data was used to predict growing steer performance. Early and repeated defoliation (T50, 20‐cm canopy cut to 10‐cm residue; S50, 10‐cm canopy cut to 5‐cm residue; and T75, 20‐cm canopy cut to 5‐cm residue) of the grasses resulted in greater herbage crude protein (CP) (202, 226, and 189 g kg−1, respectively) and lower neutral detergent fiber (NDF) concentrations (591, 572, and 596 kg−1, respectively) compared with the hay management (hay harvested at early seed head emergence followed by T75 management; 152 g CP kg−1and 620 g NDF kg−1). Cumulative metabolizable energy yield on a 1000‐ha basis tended to be highest for hay (62 138 MJ ha−1) and T75 (49 678 MJ ha−1), compared with S50 (40 373 MJ ha−1) and T50 (28 457 MJ ha−1) simply because of greater herbage mass. Greatest average daily gain was predicted when 250‐kg steers grazed T50 (0.81 kg d−1) compared with S50 (0.70 kg d−1) and T75 ( 0.71 kg d−1). Total number of grazing days per hectare was lowest for T50 (431 d), compared with S50 (580 d) and T75 (690 d). Total annual gain was greater for T75 (690 kg liveweight ha−1) management than for S50 (580 kg ha−1) or T50 (436 kg ha−1). Using herbage earlier in spring before maturation may compromise total herbage productivity, but should sustain a greater number of grazing days and livestock productivity for a given land area.

The influence of autumn management on the productivity, morphology, and botanical composition of an orchardgrass (Dactylis glomerataL.) and white clover (Trifolium repensL.) sward was investigated over 3 yr. Stockpiled (nongrazed) canopies were clipped at fixed intervals throughout autumn from exclosures established in each of nine paddocks to determine growth rates and productivity of standing herbage. Pastures were grazed by weaned lambs (Ovis aries) beginning in August in each of 3 yr. Grazing animals were removed from three replicate paddocks after 30 (early closed), 60, or 90 d (late closed). Paddocks were sampled at 2‐wk intervals to determine herbage mass, botanical composition, and total nonstructural carbohydrate concentrations of grasses and legumes. Early‐closed paddocks continued to accumulate herbage during autumn, resulting in greater senescence over winter than in lateclosed paddocks. Herbage mass in spring was not affected by autumn management. Late‐closed paddocks had significantly more clover than did early‐closed paddocks in spring. Early‐closed paddocks were comprised of grass plants that had relatively few and large tillers and by white clover plants that had fewer growing points than those in lateclosed paddocks. In comparison, late‐closed paddocks had grass plants comprised of many small tillers and white clover plants with about twice as many growing points. Stolon mass was greater, but total nonstructural carbohydrate concentrations were less during autumn in late‐ than in early‐closed paddocks. The decrease in clover mass over the course of the experiment coincided with a decrease in total herbage mass. A delicate balance between growing points and carbohydrates may be involved in clover presence in mixed swards.

Using both cool‐season (C3) and warm‐season (C4) species is a viable means of optimizing herbage productivity over varying climatic conditions in temperate environments. Despite well‐documented differences in water, N, and radiation use, no consistent evidence demonstrates productivity differences among C3and C4perennial grass species under identical management. A field study was conducted to determine relative growth rates (RGR), nitrogen productivity (NP), and mean radiation productivity (RP) (dry matter production as a function of incident radiation) of cool‐ and warm‐season grasses managed identically. Results were used to identify management practices that could lead to optimal productivity in combinations or mixtures of cool‐ and warm‐season grasses. Dry matter yields of warm‐season grasses equaled or surpassed those of cool‐season grasses, despite a 40% shorter growth interval. Certain cool‐ and warm‐season grasses appear to be suitable for use in mixtures, based on distribution of herbage production; however, actual compatibility may be altered by defoliation management. Relative growth rates varied among years and were about 40% lower for canopies clipped to a 10‐cm residue height each time 20‐cm of growth accumulated compared with other treatments. The RGR of warm‐season grasses was twice that of cool‐season grasses. Nitrogen productivity (g DM g−1N d−1) and mean radiation productivity (g DM MJ−1) for warm‐season grasses was also more than twice that of cool‐season grasses. Radiation productivity of cool‐season grasses was dependent on N, while this was not always the case for warm‐season grasses. The superior production capability of certain warm‐season compared with cool‐season grasses in a cool–temperate environment can be sustained under a range of defoliation treatments and demonstrates suitability for use in frequently defoliated situations.

Warm‐season grasses adapted to cool‐temperate environments can improve the seasonal distribution and supplement the productivity of forage systems in the northeastern USA. Management practices concerning clipping regimes for warm‐season grasses grown in the region, are not well understood. A 2‐yr field study was conducted to determine productivity and growth rates of flaccidgrass (Pennisetum flaccidumGriseb.), switchgrass (Panicum virgatumL.), bermudagrass (Cynodon dactylonL.), and Caucasian bluestem [Bothriochloa bladhii(Retz.) S.T. Blake] clipped according to sward height criteria. Treatments were replicated three times and included; first clipped at full heading; or 50% removal of short canopy and 50% and 75% removal of tall canopies at vegetative stages. Cumulative yields of warm‐season grasses were influenced by a complex clipping treatment, species, and year interaction. When first cut was made at a mature stage, 1990 and 1991 yields were similar, but were greater in 1991 than 1990 when cut early. Cumulative herbage yield of bermudagrass and Caucasian bluestem exceeded that of switchgrass and flaccidgrass when clipping was begun early in the growing season (species ✕ treatment interaction; P≤ 0.01). Mean growth rates were greatest when canopies were managed as hay or when 75% of a tall canopy was removed, and were greater in 1991 than in 1990. Instantaneous growth rates suggest that bermudagrass and Caucasian bluestem appear to be better adapted to repeated defoliation than the tall‐growing species. Switchgrass and flaccidgrass may be best used in limited‐defoliation or conserved forage situations.

Multiuse alfalfa (Medicago sativaL.) cultivars have been developed to meet the need for high‐quality and productive forages. A continuum of residual tissue quantities can occur in a stand because of management factors or livestock selectivity, depending on the production system. We conducted a field study to determine the influence of residual herbage height on the productivity and persistence of alfalfa under natural rainfall on a shallow, acidic soil (Lily series; fine‐loamy, siliceous, mesic Typic Hapludults) typical of those found throughout the Appalachian Plateau. Three replicates of ‘Alfagraze’, ‘Apollo’, and ‘Cimarron’ alfalfa in each block of a randomized complete block design were clipped to residue heights of <2, 5, or 10 cm. Averaged over the experiment, Apollo yield was greatest, at 8.7 Mg ha−1; Alfagraze (8.0) and Cimarron (7.9) yields were about 10% less than Apollo. Clipping to 10 cm produced yields that were as much as 38% less than with shorter heights. Crown density decreased from about 400 to about 80 crowns m−2during the experiment. Clipping to <2 cm caused the greatest variation in crown density among cultivars, with Alfagraze having the most and Cimarron the fewest crowns. With a 10‐cm residue, weed competition increased and plant size and shoot number were depressed, especially in Alfagraze. Plants with large crowns produced more stems, which compensated for the gradual decline in plant population. The loss of larger‐crowned plants during 1994 to 1995 was reflected in fewer shoots and reduced yield, and created a situation where increased productivity per plant could no longer compensate for plant losses. Reestablishment recommendations based on shoot numbers should be determined after the first clip in the growing season, and not in spring (when shoot numbers are changing rapidly). Our findings suggest that acceptable alfalfa yields can be obtained on a shallow acidic soil with surface liming, fertilizer input, and close clipping. The range of residue heights likely to occur in a stand of alfalfa influence productivity and persistence. Allowing a 10‐cm residue to remain would probably accelerate plant loss and yield reduction from the stand.

In temperate environments a warm‐season species is needed to provide forage during summer when the growth rate of cool‐season forages is low. Management data for warm‐season pasture is limited for the Appalachian region. A bermudagrass [Cynodon dactylon(L.) Pers.] selection RS1, has been identified which is capable of growth and persistence in areas where other cultivars of the species winterkill. A field study was conducted to determine RS1 bermudagrass productivity and quality as affected by a split application of 60, 120, 240, or 360 kg N ha−1and a 2‐, 4‐, or 6‐wk delay of initial harvest on a fine‐loamy, mixed, mesic, Typic Hapludult (Gilpin) soil. Treatments were replicated four times in the field, and the study was conducted for 2 yr. Delaying initial harvest significantly increased yield in both years to more than 8 Mg ha−1when 360 kg N ha−1yr−1was applied. Herbage yields typically ranged between 3 and 6 Mg ha−1and would contribute substantially to forage requirements in mid‐summer in the region. Increased N resulted in higher herbage yield regardless of harvest delay regime. Herbage yields were about 25% less in 1989 than in 1988 and could be due in part to cool and wet conditions in 1989, compared to a hot, dry 1988 growing season. Bermudagrass in vitro dry matter digestibility and crude protein declined with delayed initial harvest (maturity), increased following the mid‐season N application, and continued to decline into late summer. Season average quality was not affected by initial harvest delay. Bermudagrass (RS1) will persist and respond to N fertilizer and defoliation management in cool, temperate environments and promises to be a useful component in forage‐based animal production systems in the region

Knowledge of seasonal distribution of herbage growth is essential for design of pasture management schemes that optimize season‐long herbage productivity and nutrients for grazing livestock. Current knowledge of cool‐season grass growth is derived largely from either hay production or high‐input systems. A 3‐yr field study was conducted to determine the productivity and growth rates of cool‐season grasses defoliated according to sward height criteria in a marginal soil environment. Defoliation regimes included hay harvest, lenient (50%) removal of short (10 cm) canopies, and both lenient and intensive (75%) removal of tall (20 cm) canopies. Species included orchardgrass (Dactylis glomerataL.), fescue × perennial ryegrass hybrid (Festuca arundinaceaSchreb. × Lolium perenneL.), and prairie grass (Bromus willdenowiiKunth). Cumulative yield curves were fit to the Gompertz growth equation and growth rates were derived from the fitted data. All species had low yields relative to other defoliations and growth rates when managed for removal of 50% of canopy height regardless of height. Managing pastures on the premise of take half, leave halfmay not always contribute to plant persistence and sustained productivity. Frequent defoliation beginning in spring resulted in a greater portion of annual yield occurring in late than in early season, resulting in more stable distribution but less herbage within a season, compared with canopies managed as hay. High growth rates of prairie grass early in the study were followed by stand degradation, regardless of defoliation treatment, and may indicate unsuitability for use in low‐input or marginal environments. Autumn recovery of herbage production did not occur under any defoliation regime.

Reported β‐glucanase activity by amyloglucosidases used in starch determination might lead to significant overestimates of starch concentration in plant tissue. To test this hypothesis, two amyloglucosidases and a porcine α‐amylase were evaluated using four starch and three β‐glucan preparations. The enzymes were also used to estimate starch concentration of alfalfa (Medicago sativaL.) roots and tall fescue (Festuca arundinaceaSchreb.) and orchardgrass (Dactylis glomerataL.) stem bases. Release of reducing sugars by the α‐amylase was consistent with 95 to 98% hydrolysis of starch to maltose, and <3% hydrolysis of β‐glucans. The widely used amyloglucosidase from Rhizopusgave 89 to 93% hydrolysis of starch, but also 35 to 83% hydrolysis of β‐glucans. Hydrolysis with α‐amylase gave calculated starch concentrations for the grasses which were not significantly different from zero, but the Rhizopusenzyme gave starch estimates of 32 and 52 g kg−1for tall fescue and orchardgrass, respectively. The amyloglucosidase from Aspergillusgave intermediate results. Neither amyloglucosidase should be used to estimate plant starch concentration.