Vetches in southern Queensland
Vetches are winter-growing legumes
Vetches are winter-growing legumes that can provide beef and dairy producers with a means of improving animal performance during winter. They are worth considering in situations where soil nitrogen levels are low and you may be reluctant to use heavy rates of nitrogen fertiliser on oats or other winter cereals.
Advantages of vetches
The vetches have a number of advantages over other fodder crops. These include:
- Capable of producing reasonable quantities of high protein feed. Some types only have a very narrow planting window. Match the vetch type to the production system in use.
- Vetches have relatively low bloat risk. While bloat is not generally regarded as a problem with cattle grazing woolly pod or purple vetch, some caution should still be exercised as there have been occasional cases of bloat with Golden Tares.
- Vetches are large seeded and capable of being planted down into soil moisture. This is in contrast to the smaller seeded fodder legumes such as medics, which often require a sequence of rainfall events after planting to ensure successful establishment.
- They have useful tolerance to the triazine group of herbicides (e.g. atrazine). This enables vetch to be double-cropped after sorghum or maize provided that excessively high rates of atrazine have not been used in the preceding summer cereal. Any likelihood of crop damage to the vetch will be further minimised by only planting in situations where there is a reasonable profile of sub-soil moisture at planting (60 cm wet soil).
- They are adapted to a broad range of soils ranging from acidic granite and sandstone soils through to highly alkaline clays. They are more tolerant to acid soils than most other legumes. Namoi will generally outperform the other vetches on acidic, light-sandy soils. Namoi and Popany have both performed well in floodplain country and will tolerate some waterlogging.
A range of different vetch species are available to producers. Each of these have very specific management requirements that need to be carefully matched up with the growers requirements (i.e. the production system being used, planting time, and soil type).
While vetch is regarded as drought-tolerant it will defoliate under severe moisture stress. All the vetches are moderately frost sensitive and seedlings can be cut back severely by heavy frosts.
Common vetch (Vicia sativa)
- Are mainly relatively short season, early maturing types which are more suited to grain or dual purpose situations.
- Most common vetches are susceptible to rust (uromyces viciae-fabae), which can devastate crops during spring.
- Morava is the only commercial variety with resistance to rust, and is the only common vetch variety recommended for Queensland. Morava is held under plant breeder's rights (PBR) by Paramount Seeds South Australia (08) 9071 1053.
- Lanquedoc, Blanchfleur, Cummins, Velero, Vestar and Vedura are all susceptible to rust, and are considered an unacceptable rust risk under our conditions.
- The cultivar Golden Tares is a much later maturing vetch (one month later), and is more suited to fodder production only.
Purple vetch (Vicia benghalensis)
- Long season, late maturing annuals suitable for fodder production in cropping country.
- Regenerates poorly and not suitable for permanent pastures.
- Relatively good tolerance to waterlogging.
- Main cultivars are Popany and American Purple.
Woolly pod vetch (Vicia villosa spp. dasycarpa)
- The cultivar Namoi is a medium-late maturing cultivar with very high levels of 'hard' seed. It is more suited to permanent pastures.
- Namoi is not recommended in cropping country where regeneration could be a problem in cereal crops.
- New varieties held under PBR include Capello and Haymaker Plus. Both are available through SeedCo (08) 8234 9333.
Bitter vetch (Vicia ervilla)
- Untested in Queensland, but likely to be more suited to grain production.
May-June has traditionally been the main planting time when planting vetches for either forage or grain. Purple vetches such as Popany can either be sown in March for winter grazing, or in May for spring grazing.
Seeding rates vary from 3-10 kg/ha. The heavier rates are preferred when sowing a pure sward for forage. Seed should be treated with Group E inoculum. Lime pelleting is recommended when planting into acid soils below pH 5.5.
It is very important to use grazing to avoid situations where you have very rank growth during late winter (July-September). Rank, vegetative crops of Popany and common vetch (Morava) are extremely susceptible to botrytis grey mould. This foliar disease can devastate a crop in a matter of weeks.
Management should aim at allowing the vetch to seed down in the establishment year, in order to build up reserves of hard (dormant) seed in the soil. Subsequent spelling every second or third spring is advisable to allow the seed reserves to be maintained. Namoi does not persist under continuous, uncontrolled grazing by sheep or goats, or on hard setting soils such as traprock or fine-grained sandstones (except where they are periodically cultivated).
A well managed stand can produce between 200 and 600 kg/ha of seed. While Namoi can be harvested with conventional equipment, crop lifters are often necessary. Sowing the vetch with 15 kg oats/ha will help lift the vetch off the ground and aid harvesting.
Vetch hay is nutritious (16-20% protein), highly palatable and preferred by livestock. Slashers or rotary type mowers are preferred for hay making operations. Conventional cutter-bar type mowers are not suitable as they are prone to blockages from the vining growth.
Vetches are not suited to close grazing. They are climbing plants, with their growing points situated well above ground level. The type of grazing management required will largely be governed by whether the vetch is sown by itself, or in a mix with cereals such as oats.
Namoi is not highly palatable to cattle, and in a mixed sward the cattle will normally graze the grasses and broadleaf weeds in preference to the vetch. Stricter grazing management will be required where Namoi is sown as a pure stand however, in order to prevent overgrazing and damage to the vetch.
Occasional palatability problems have also been experienced with Popany purple vetch. This problem usually occurs around flowering.
Namoi should not be sown in cropping country because of its hard seed levels and ability to regenerate in cereal crops for years after.