Vicia villosa Roth.
|Author: John Frame|
Hairy vetch, winter vetch, fodder vetch, woollypod vetch.
Hairy annual or biennial with scrambling and climbing habit up to 2 m. Whole plant has a white-woolly appearance because of the long soft hairs. Shallow taproot system with strong lateral branches. Leaves compound pinnate with 4-12 pairs of opposite leaflets tapering towards the apex and 2-3 branched terminal tendrils. Leaflets narrowly ovate, stipules small and narrow. Racemose inflorescences with 10-20 flowers borne on long stalks arising at the base of the leaves; self-fertilized flowers mainly purple to blue in colour but sometimes white. Elongated flattened pods contain 2-8 rounded seeds ranging from dark brown to greyish black in colour.
Native to southern Europe. Utilized there mainly in vetch/cereal mixtures but much less than common vetch (Caballero, 1993) while it is much more important than common vetch in the USA (Miller and Hoveland, 1995). Introduced to continental, west and central Asia and other temperate areas. Can be autumn-sown to provide green manure in rotations with conventional and no-till planted rows through mechanically or chemically killing the vetch in spring 2-3 weeks before planting the new crop or else it can be sprayed at planting (PLANTS database 2000).
Adapted to a range of soils from fine- to coarse-textured but not acidic or saline soils. Rapid growth rate. Intolerant of shade. Sprawling growth form but grows upright when sown with a companion cereal, e.g. with oats and to a much lesser extent with barley or wheat in the Mediterranean area (Caballero, 1993).
Season of growth
Mainly spring to summer whether spring- or autumn-sown.
Fairly cold hardy and more so than common vetch.
Intolerant at early stage of establishment but medium tolerance thereafter.
Prefers well-drained, moderately fertile soils, pH 6.0-7.5 (PLANTS database 2000). Responds to P fertilization. More tolerant of poorly-drained soils than common vetch (Hoveland and Donnelly 1966). In general vetches (Vicia spp.) are more tolerant to soil acidity than many forage legumes.
Rhizobial inoculation of seed advisable if grown on land where species not grown before.
Land preparation for establishment
Well-cultivated, uniform and firm seed bed required for good results.
Normally drilled whether sown pure or in combination with cereals but can also be broadcast. It is sometimes sown with Bermuda grass (Cynodon dactylon). Can be direct drilled (sod seeded) into warm-season grass swards to extend grazing season (Blanchet et al. 1995), e.g. into switchgrass (Panicum virgatum).
Sowing depth and cover
Sown at 2-4 cm with a good soil cover.
Sowing time and rate
Spring or autumn depending on farming system and severity of winter conditions, but mainly autumn in the USA, for example. Seed rates 25-50 kg/ha in monocultures and 15-25 kg/ha when in combination with 50-80 kg/ha of a cereal such as rye.
Number of seeds per kg
35 000 to 45 000.
The main requirement is for phosphate, at an application rate dependent on the soil P status.
Vigour of growth
Vigorous growth once well established.
High (PLANTS database 2000). LaRue and Patterson (1981) report fixation of 184 kg/ha N.
Dry matter yields
At nil N fertilization Moreira (1989) obtained 5.81-6.56 t/ha in northern Portugal from autumn-sown vetch and 5.12-8.34 t/ha with applied N at rates up to 100 kg/ha; vetch/oat mixtures and oat monocultures generally outyielded vetch monocultures substantially when fertilizer N was applied but not at nil N application. For central Spain, Haj Ayed et al. (1995) reported 6.51 t/ha from hairy vetch with nil N application, a higher yield than that obtained (5.82 t/ha) from oat/vetch mixtures, though an oat monoculture yielded 11.00 t/ha. In Alaska, pure-sown vetch yielded 4.04-4.75 t/ha on a neutral soil and N application increased yields but on an acid soil the yield was lower (3.46 t/ha) and was reduced by N fertilization (Panciero and Sparrow, 1995).
Suitability for hay and silage
Can be used for hay or silage. When grown for hay it is normally cut when the first pods are set.
Valuable source of protein and minerals. Panciero and Sparrow (1995) reported CP contents of 16.4-17.9% on neutral soil and 13.6-14.7% on acid soil. On a DM basis average values in spring of autumn-sown V. villosa and V. sativa in north-west Spain were 25.1% in April and 17.3% in May; correspondingly, acid detergent fibre (ADF) values were 28.2% and 32.6% (Iglesias and Lloveras, 1998). At growth stages 30% and 60% DM in pod seeds, mean whole plant CP content was 17.3% and 14.6%, respectively and digestible dry matter (DDM) 60.4% and 56.2% (Caballero et al., 1995c). Plant part composition is shown in the Table.
Table: Mean fibre (ADF), protein (CP) and digestible dry matter (DDM) values of plant parts at two growth stages (30% and 60% DM in pod seeds) of hairy vetch (Caballero et al. 1995c)
Highly acceptable as grazed or conserved forage.
Can be grazed by a range of livestock, including zero grazing (green fodder cut and carried). Lax grazing necessary in order to leave the basal axillary buds which are the regrowth sites.
400-1500 kg/ha in the USA (Miller and Hoveland, 1995).
USA cultivars include Madison, Americus, AU Early Cover and Lana; Glabrescens is a Spanish cultivar (Caballero et al., 1995c).
Several pests which can sometimes cause plant damage in the USA are listed by Miller and Hoveland (1995): pea aphid (Acyrthosiphon pisum), corn earworm (Heliothis zea), fall armyworm (Spodoptera frugiperda) and spider mite (Tetranychus spp.). The seed of hairy vetch, but not common vetch, is susceptible to damage by the vetch bruchid (Bruchus brachialis) and so natural reseeding in pastures is poor.
Short-term catch crop. High nutritive value. Protein-rich, highly acceptable feed for different classes of stock. Valuable constituent of vetch/cereal mixtures.
Moderate yield and quality. Ideally requires companion cereal species to avoid lodging and harvesting difficulties which occur with monocultures.