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Swards of four cultivars of subterranean clover (Trifolium subterraneum L.) were cut at three different times to determine the effect on forage yield and quality, seed set and seedling regeneration in two successive seasons in southern New South Wales. The four cultivars of subterranean clover (Seaton Park LF, Junee, Goulburn and Clare) were cut on 23–25 September (early cut), 8–10 October (mid cut) or 22–23 October (late cut), to simulate an early silage, late silage or hay cut. Additional treatments imposed included either grazing or leaving the regrowth after cutting and raising the cutting height from 3 to 6 cm.Forage yields ranged from 3.5 to 9.3 t dry matter (DM)/ha in the first year and from 2.0 to 5.9 t DM/ha in the second year. Herbage yield was influenced by both cultivar and harvest time with the highest yields achieved with the mid cut. Lower forage yields at the later cut were attributed to losses due to respiration and decay under dense leaf canopies. Changes in forage quality were consistent across both years, with in vivo DM digestibility declining from 76–79% to 69–70% as cutting time was delayed. Crude protein fell from 22–24% to 14–17% over the same period, depending on cultivar. Seed yields in both years were influenced by both cutting time and cultivar with a positive relationship (R2 = 0.45–0.61) between herbage present in late spring after a period of regrowth and subsequent seed yield. The early flowering cultivar Seaton Park LF had the highest seed yield in both years and the more erect cultivar Clare had the lowest. Seed yields declined with later cutting time but increased by an average of 39% when the cutting height was raised from 3 to 6 cm. Seedling regeneration reflected seed yield responses with the largest seedling regeneration occurring in treatments cut early.The study found that forage conservation in early October is likely to yield more and be of higher quality than swards cut later in the season. Seed set is greatly reduced by all cutting strategies to levels unprofitable for seed harvesting but may be adequate for pasture regeneration. [ABSTRACT FROM AUTHOR]

Ninety-one perennial legumes and herbs (entries) from 47 species in 21 genera were evaluated at sites in New South Wales, South Australia and Western Australia over 3 years from 2002 to 2005 to identify plants with superior herbage production, persistence and the potential to reduce ground water recharge. Evaluation was undertaken in three nurseries (general, waterlogged soil and acid soil). Medicago sativa L. subsp. sativa (lucerne) cv. Sceptre was the best performing species across all sites. In the general and acid soil nurseries, Cichorium intybus L. (chicory) cv. Grasslands Puna was the only species comparable with Sceptre lucerne in terms of persistence and herbage production. Trifolium fragiferum L. cv. Palestine and Lotus corniculatus L. SA833 were the best performing species on heavy clay soils prone to waterlogging. Three Dorycnium hirsutum (L.) Ser. accessions persisted well on acid soils, but were slow to establish. Short-lived perennial forage legumes, such as Onobrychis viciifolia Scop. cv. Othello, and three Hedysarum coronarium L. entries, including cv. Grasslands Aokou, had high herbage production in the first 2 years and may be suitable for short-term pastures in phased pasture-crop farming systems. T. uniflorum L. and M. sativa subsp. caerulea SA38052 were highly persistent and could play a role as companion species in mixtures or ground cover species for undulating landscapes. Cullen australasicum (Schltdl.) G.W. Grimes SA4966 and Lotononis bainesii Baker cv. Miles had poor establishment, but were persistent. Chicory, T. fragiferum and L. corniculatus were identified as species, other than lucerne, with the most immediate potential for further selection to increase the diversity of perennial legumes and herbs adapted to southern Australian environments. [ABSTRACT FROM AUTHOR]

Increasing the proportion of the landscape planted to deep-rooted perennial pasture species is recognised as one of several remedial actions required for the control of dryland salinity in southern Australia. The widespread use of perennials in farming systems is limited at present by the lack of well-adapted perennials that can be grown to reduce recharge in a landscape where drought, soil acidity, temporary waterlogging, infertile soils and unrestricted grazing prohibit the use of many species. The range of plants adapted to salinity also needs to be expanded to stabilise and ameliorate soils already degraded by rising watertables and to increase the profitability of grazing discharge regions within the landscape. This paper describes the steps involved in a national forage screening and breeding program initiated by the Cooperative Research Centre (CRC) for Plant-based Management of Dryland Salinity1, seeking to expand the range of perennial and or salt-tolerant forage plants that can be incorporated into farming systems of southern Australia. It describes the target environments, soil constraints, farming systems and the criteria being considered when assessing the potential of new plants, including assessment of the weed risk posed by introducing new species. This paper forms an introduction to a special issue which presents the outcomes of the pasture species field evaluation and plant breeding program conducted by the CRC. [ABSTRACT FROM AUTHOR]

Izmir is a hardseeded, early flowering, subterranean clover of var. subterraneum (Katz. et Morley) Zohary and Heller collected from Turkey and developed by the collaborating organisations of the National Annual Pasture Legume Improvement Program. It is a more hardseeded replacement for Nungarin and best suited to well-drained, moderately acidic soils in areas with a growing season of less than 4.5 months. Izmir seed production and regeneration densities in 3-year pasture phases were similar to Nungarin in 21 trials across southern Australia, but markedly greater in years following a crop or no seed set. Over all measurements, Izmir produced 10% more winter herbage and 7% more spring herbage than Nungarin. Its greater hardseededness and good seed production, makes it better suited to cropping rotations than Nungarin. Softening of Izmir hard seeds occurs later in the summer?autumn period than Nungarin, giving it slightly greater protection from seed losses following false breaks to the season. Izmir is recommended for sowing in Western Australia, New South Wales, Victoria, South Australia and Queensland. Izmir has been granted Plant Breeders Rights in Australia. [ABSTRACT FROM AUTHOR]

The effect of harvest time on the dry matter (DM) yield and quality of 10 annual temperate legumes [Trifolium subterraneum, var. brachcalycinum and var. subterraneum L. (subterranean clover), T. michelianum Savi (balansa clover), T. alexandrinum L. (berseem clover), Medicago murex Willd. (murex medic), M. truncatula Gaertn. (barrel medic), T. vesiculosum Savi (arrowleaf clover), Vicia sativa L. (common vetch), V. benghalensis L. (purple vetch), Pisum sativum L. (peas) grown in monoculture or in mixtures with oats (Avena sativa L.)] was examined in a Mediterranean environment in southern New South Wales. Three of the legumes (subterranean clover, berseem and peas) were also grown in mixtures with ryegrass (Lolium multiflorum Lam.). The forages were sown on 29 May and harvested at three times (2 October, 23 October and 6 November), corresponding to the boot, anthesis and dough stage of the cereal oat variety, Kalgan. Peas were the highest yielding of the legume monocultures at each of the three harvest times (6.9, 11.6, 12.3 t DM/ha), followed by purple vetch (6.2, 9.9, 8.7 t DM/ha). Of the small-seeded pasture legumes, berseem, murex and arrowleaf clover were the highest yielding at the second harvest (7.5?8.8 t DM/ha) when most reached their peak biomass. The inclusion of oats with the legumes increased total DM yield at the first, second and third harvests by 10?54, 7?99 and 3?102%, respectively. Oat monocultures were high yielding (up to 17.7 t DM/ha), but had low N contents (6.3?12.5 g N/kg DM). Oat?legume forage mixtures had nitrogen (N) contents of 7?15 g N/kg compared with 17?40 g N/kg in the legume monocultures. The N content and digestibility of most species and mixtures decreased as harvest time was delayed, whereas total DM peaked at the second harvest for all species except Cooba oats. The legume content of the mixtures was negatively correlated with total DM yield, DM content and water soluble carbohydrates, but positively correlated with N content, in vitro digestibility and buffering capacity. The digestibility of oats decreased more rapidly than the legumes with advancing maturity, and it would need to be harvested at the boot stage to produce a silage of sufficiently high metabolisable energy for the production feeding of cattle. A later harvest at anthesis when yield is higher would produce a silage of sufficient quality for production feeding from an oat?large seeded legume mixture with a legume content of 0.50. The oats and ryegrass had high water soluble carbohydrate and low to medium buffering capacity and would, therefore, be expected to produce well-preserved silages. The legume monocultures had low water soluble carbohydrate contents and high buffering capacity values and there would be a high risk of a poor silage fermentation in these forages without field wilting or the use of a silage additive. [ABSTRACT FROM AUTHOR]

Coolamon is a mid-season to late-season flowering F4-derived crossbred subterranean clover of var. subterraneum, developed by the collaborating organisations of the National Annual Pasture Legume Improvement Program. It is a replacement for Junee and has been selected for release on the basis of its greater herbage production and persistence, and its resistance to both known races of clover scorch. Coolamon is recommended for sowing in Western Australia, New South Wales, Victoria, South Australia and Queensland. It is best suited to well-drained, moderately acidic soils in areas with a growing season of 6.5?8 months that extends into November. Coolamon is best suited to phase farming and permanent pasture systems. It can also be used in cropping rotations, but at least 2 years of pasture are required between crops. Coolamon has been granted Plant Breeders Rights in Australia. [ABSTRACT FROM AUTHOR]