It’s not really summer until birdsfoot trefoil starts showing up everywhere, which is is. So it is in Australia, as the folllowing indicates.
•Perennial, non-bloating, adapted to acid and waterlogged soils.
•Provides bypass protein, and reduces methane output in ruminants.
•Seed can be expensive and seedling establishment is slow.
•Needs carful grazing management over summer to maintain persistence.
Plant: Herbaceous tap rooted perennial that can have an erect to prostrate growth habit.
Stems: Usually hairless and solid (not usually hollow), green to reddish green, up to 60 cm long, arising from the basal crown. Branches arising from the leaf axis.
Leaves: Leaves occur as five leaflets (pentafoliate), three terminal and two basal and are nearly hair-less. The widest part of the leaf is in the lower half of the basal leaflets. Leaf shape can vary (elliptic or obovate) however terminal leaves are at least 3 times longer than their width. The three terminal leaves are also removed from the basal leave hence the Trefoil component of the common name.
Flowers: Inflorescence is umbel like. Flowers are yellow often but not always with red veins in the petals. Flowers occur in groups of 2 through to 8 (mostly 3 to 5) and are approximately 10 to 16 mm long.
Pods: Pods are usually brown, long cylindrical in shape and 15 to 40 mm in length. Pods shatter to disperse seed as they ripen. The pod arrangement off the stem is a mirror-image of a Birdsfoot, hence its common name.
Seeds: Seeds are greyish brown to black about 1 mm long (1 x 106 seeds/kg).
Pasture type and use
Birdsfoot Trefoil is most successful in areas where white clover is unable to perenniate due to an extended summer drought and Lucerne is unable to be productive due to low soil pH and/or winter waterlogging.
Birdsfoot is used primarily in combination with cocksfoot on acid soils and can be used with phalaris in waterlogged soils. It is also used in native pastures of South America.
Where it grows
> 600 mm average annual rainfall
Suited to a wide range of soils with low pH (<5.5 in CaCl). Also tolerates waterlogging.
Cold and frost tolerant.
Grasses: Cocksfoot, Phalaris, Tall fescue, Kikuyu and Paspalum.
Legumes: subterranean clover, strawberry clover and white clover.
Sowing/planting rates as single species
4 to 8 kg/ha (not commonly sown by itself)
Sowing/planting rates in mixtures
2 to 4 kg/ha
Autumn or spring sowing at a depth of 0.5 to 1.5 cm into a firm, level, weed free seedbed. Can also be drilled into perennial grass stands, although grazing is required to manage the green over burden.
Special Lotus corniculatus inoculant.
Phosphorus and any other nutrients required to avoid deficiencies.
Olsen P soil test for phosphorus above 15
Birdsfoot trefoil is suitable for hay or silage production. Hay production should be cut at 10% flowering. Cutting after 10% flowering will result in reduced feed quality while cutting before 10% flowering will result in reduced quantity. Cutting height should not be below 8 cm to facilitate re-growth.
New stands should be allowed to reach 10% flowering before grazing and subsequently rotationally grazed. Continuous grazing of birdsfoot trefoil will reduce root carbohydrate reserves, resulting in stand decline. To ensure carbohydrate reserves are not depleted to critical levels, grazing or cutting should not be below 8 cm. Any stand decline can be rectified by allowing seed set. Subsequent autumn rains will establish new seedlings, some of which will survive to become adult plants. To assist seedling survival the stand should be grazed to reduce shading. It is recommended that thickening of stands be undertaken every two to three years.
Pods shatter dispersing seed so several important management practises need to be considered including; monitoring of peak flowering and podding, the application of a desiccant such a paraquat at 70 percent pod maturity or at 35 days after peak flowering, harvesting with a conventional header 48 hours after the desiccant application with header concave settings at 2 mm and drum speed at 1200 rpm using a very low fan speed setting for air flow.