Spring vetch

Economic importance

Spring vetch (common vetch) is one of the most important forage crops. It produces green mass with a high protein content and has good technological properties, which allows it to be used for preparing feed for winter.

100 kg of green mass harvested at flowering contain 16.5–20 feed units and 4–4.5 kg of digestible protein. 100 kg of hay contain 45.8 feed units and 6.8–12.3 kg of digestible protein. 100 kg of grain contain 116 feed units and 22 kg of digestible protein.

For feed purposes, seeds, chaff and straw of spring vetch are used. 1 feed unit corresponds to digestible protein content: in hay — 295 g, in green mass — 274 g, in grain — 196 g, in straw — 100 g.

In the green mass of aftercut and stubble sowings, the protein content is higher. For example, the protein content in the green mass of spring vetch sown in spring was 17.6%, in aftercut sowing — 22.3% (VNII of Feed).

Stubble and aftercut sowings help clean fields of weeds, reduce or prevent water or wind erosion, and enrich the soil with organic matter and nitrogen.

It has a slightly bitter taste due to the alkaloids vicine and vicinine contained in it, so in pure stands it is not eaten very well by animals. This is one of the reasons why it is grown in mixtures with other well-palatable crops, usually with cereals. Such mixtures are usually also higher-yielding.

Spring vetch and its mixtures with other crops are of great agronomic importance. In the forest-steppe zone, it is the most common fallow-occupying crop and serves as a good predecessor for grain and other crops in crop rotations. It often acts as an insurance crop in years unfavorable for overwintering of perennial legumes. To compensate for forage areas of failed sowings, they are often reseeded with a vetch–oat mixture. Together with root and stubble residues of spring vetch, 40–50 kg/ha of nitrogen enters the soil.

Stubble sowings of vetch–oat mixture produce high yields on irrigated lands of the North Caucasus, Moldova, and southern Ukraine.

Crop history

Spring vetch is considered an ancient crop originating from Western Asia and the Mediterranean, where it occurs in natural plant communities.

In Russia, it has been cultivated since the 15th–16th centuries in the forest and forest-steppe zones, as well as in the north of the steppe zone.

Cultivation areas

It is cultivated in the Non-Chernozem zone, forest-steppe regions with sufficient moisture in the Central Chernozem zone, and Western Siberia. In arid regions and areas with insufficient moisture, it is rarely grown.

Yield

The yield of green mass of vetch and its mixtures in the forest-steppe zone is approximately 15–25 t/ha, hay — 4–6 t/ha, seeds — 1500–2000 kg/ha.

Botanical description

Spring vetch, or common vetch, (Vicia sativa L.) is an annual leguminous plant.

The root is taprooted and well developed.

The stem is thin, climbing, lodging, up to 50–100 cm long.

Leaves are even-pinnate, with 5–8 pairs, ending in tendrils.

The inflorescence includes 1–2 axillary sessile flowers, purple or red in color.

The fruit is an elongated, many-seeded pod. Seeds are round or slightly flattened, dark, gray-green, or white. The weight of 1000 seeds is 40–75 g.

Biological characteristics

Spring vetch is a long-day plant. With a day length of 13–13.5 hours, plant height decreases and the formation of generative organs stops.

Common vetch is a cold-resistant crop with low heat requirements. Seeds begin to germinate at 2–3 °C; the optimal temperature for uniform emergence is 8 °C.

It tolerates frosts down to −5…−7 °C. The optimal temperature for green mass formation is 12–16 °C, for seed ripening — 16–20 °C.

The sum of active temperatures for green mass formation is 900 °C, for seeds — 1900 °C.

Common vetch is a moisture-loving crop. When the sum of precipitation for May–July is 90–130 mm, hay yield is no more than 1.5 t/ha; with moisture of 200–230 mm it reaches 4–6.5 t/ha. Maximum water consumption occurs during flowering. Optimal moisture conditions develop when the annual precipitation sum is at least 450 mm.

It is relatively demanding regarding soils. The soil should have a neutral or slightly acidic reaction; optimal acidity pH is 5.0–6.5 (according to other data, pH 6.0–6.8). It prefers cohesive fertile chernozems and lowland peat bogs. Waterlogged, heavy, puddled, swampy, solonetzic, and sandy soils are unsuitable.

Vegetation

During seed germination, the cotyledons remain in the soil. The first 2–3 leaves have only one pair of leaflets. On the 5th–6th day after emergence, growth of the main stem stops and branching begins.

Before flowering begins, stems develop slowly; average daily growth is no more than 1.5 cm, and plant height does not exceed 50 cm. During this period, 43–45% of the forage mass is formed.

The flowering phase is extended. Flowers open from the lower tier of the plant to the upper. Pods begin to form from the lower flowers, while the upper ones are only flowering.

Depending on weather conditions, flowering may last 20–30 days. It is a facultative self-pollinator. In the period from the beginning of flowering to the formation of the first pods, average daily stem growth is 3.0–3.5 cm, and average daily green mass growth increases from 4.7–5.1 to 11.7–15.5 centners/ha.

By the time of pod formation, plant height reaches 80 cm. By this period, the maximum dry matter yield is formed with the highest content of protein and nutrients.

Flowering begins 40–60 days after sowing, cutting ripeness — after 55–70 days, seed ripening — after 75–120 days (depending on the variety).

Total duration of the growing season for:

• early-ripening varieties is 75–90 days;
• mid-ripening — 110–120 days;
• late-ripening — up to 140 days.

Crop rotation

In the forest-steppe zone, in crop rotations, vetch and its mixtures for forage are placed after spring cereals and row crops in occupied fallow.

In field crop rotations, it is placed in a fallow field; harvesting for hay or green fodder is carried out as early as possible in order to prepare the soil for sowing winter crops.

When grown for grain, it is placed after cereals or row crops.

The vetch–oat mixture is suitable for cultivation on newly developed virgin and fallow lands.

Fertilization

Spring vetch responds to the application for basic soil cultivation of manure at 20–40 t/ha and P_45-60K_45-60.

Acidic soils are limed.

At sowing, 50 kg/ha of granular superphosphate is applied simultaneously in the rows.

Tillage

Basic and pre-sowing soil tillage is similar to tillage for early spring cereal crops.

Sowing

Sowing for forage purposes begins in early spring, usually in a mixture with oats or other support crops.

Pre-sowing seed treatment includes dressing, treatment with bacterial preparations (pea rhizotorfin) on the day of sowing, and molybdenum micronutrient fertilizers. Bacterial preparations help increase hay yield by 15%. Molybdenum micronutrient fertilizers are especially effective in the Non-Chernozem zone.

Under conditions of sufficient soil moisture, to ensure a green conveyor, the vetch–oat mixture is sown in 2–3 dates with an interval of 7–15 days, as well as aftercut and stubble.

The sowing method is conventional row sowing simultaneously with the cereal; the ratio of components in the mixture is determined taking moisture into account. In the forest-steppe zone, with sufficient moisture supply, the share of oats is increased to prevent early lodging of the herbage; in the arid steppe, it is reduced so that vetch is less suppressed.

The highest protein yield is obtained with a ratio of vetch and oat seeds of 2–3:1. The higher the share of vetch in the mixture, the earlier and more severe the lodging of the herbage. Therefore, the ratio of components is also determined taking into account the purpose of using the vegetative mass:

• for green fodder — 2–3:1;
• for hay — 1–2:1;
• for haylage and silage — 1:1.

If later harvesting is planned, the share of the cereal component is increased to prevent lodging of the herbage.

The total seeding rate for cultivation for forage purposes is 4–5 million seeds/ha, or 180–220 kg/ha.

Seed placement depth is 3–6 cm.

For late sowing dates, moisture-loving and non-heat-resistant oats can be replaced by drought- and heat-resistant cereal grasses, for example, Sudan grass, sorghum–Sudan hybrid, millet, paiza, chumiza, mohar. Moreover, under conditions of sufficient moisture in the second half of summer, some of them allow a second cut or aftermath, especially Sudan grass and paiza. The total seeding rate for such grass mixtures is 100–120 kg/ha, of which 80–100 kg/ha is vetch and 20 kg/ha is Sudan grass.

For summer sowing dates of vetch–cereal mixtures (aftercut), the seeding rate is increased by 20–25%.

In some cases, repeated sowings of spring vetch can be used, sown immediately after harvesting the first crop. In this case, the field is cultivated immediately and sowing begins. Delay in sowing leads to a sharp decrease in yield. The seeding rate for repeated sowing is increased by 15–20% compared with spring sowing. The seed placement depth is, as a rule, increased to 4–5 cm, since shallower placement causes thinning of the stands.

Crop care

After sowing, the soil is rolled with subsequent harrowing with light harrows. This technique is especially important for late-spring and summer sowing dates to prevent rapid drying of the upper soil layer.

Forage sowings of vetch with oats or other forage crops are, as a rule, little damaged by pests and diseases; severe weed infestation is also rare, so chemical control agents are used very rarely.

Harvesting

Harvesting for green fodder and hay begins during full flowering of vetch. Harvesting for haylage and silage — at the stage of seed filling in the lower pods.

Optimal harvesting dates also depend on the composition of the herbage. The greater the share of spring vetch, the closer the harvesting dates are shifted to the beginning of pod formation. If oats predominate in the herbage, harvesting dates are shifted to the panicle emergence phase, since later harvesting dates lead to coarsening of oats and a decrease in feed quality.

Growing for seed

For seed purposes, spring vetch is usually sown in a mixture with another component as a support crop with a sufficiently strong stem, low leafiness, and similar growth and development. Usually this is oats or white mustard. Early-ripening vetch varieties can be sown, in addition to late-ripening oats, also with barley and white mustard.

When choosing a site for seed plots, the soil must have an acidity of not less than pH 4.5 (optimally pH 6.5–7.0), since on acidic soils spring vetch does not flower or produces a low yield of shriveled seeds. It is placed in a field where manure was applied 2–3 years earlier. Placing seed plots after a manured field can cause severe lodging of plants and poor ripening.

To form 1 t of seeds with a corresponding amount of aboveground mass, spring vetch removes from the soil 15 kg P₂O₅, 18 kg K₂O, and 65 kg N. Therefore, to obtain a high seed yield, phosphorus and potassium fertilizers should be applied. Application of 90 kg/ha P₂O₅ as superphosphate increases seed yield by 25–30% and shortens the growing season by 4–5 days. The greatest stem strength of oats sown in a mixture with spring vetch is achieved with the application of P60K60 (VNII of Feed). Good results are also given by application of phosphorite meal for autumn plowing at 400–500 kg/ha.

Before sowing, seeds are treated with molybdenum micronutrient fertilizers at the rate of 50–100 g of molybdenum dissolved in 2 L of water per hectare seed rate.

To prevent the development of diseases (ascochyta blight, rots, anthracnose, bacteriosis, mold, etc.), seeds are dressed with Fundazol, TMTD, and Aktamyr.

For seed cultivation, the recommended ratio of vetch and oats is 2:1. In the northwest of the Non-Chernozem zone (Leningrad Oblast), the share of vetch is reduced to 0.35–0.5 relative to oats. In the northern regions of the Central Chernozem zone, the highest yields are obtained with a ratio of 3:1. In the central regions of the Non-Chernozem zone, the best results are obtained with a seeding rate of 5.5 million/ha, including 1.1 million spring vetch seeds and 4.4 million oat seeds, or in weight terms — 50 kg/ha spring vetch and 150–160 kg/ha oats.

According to data from the Lgov Experimental Breeding Station of VNIIS, in the Central Chernozem zone the best results are achieved with a seeding rate of 110–120 kg/ha vetch and 50–60 kg/ha oats. In Western Siberia, the recommended seeding rate is 80 kg/ha vetch and 120 kg/ha oats. In the Urals — no more than 1 million/ha oat seeds and 2.2 million/ha spring vetch seeds.

Good results are obtained with joint sowing of vetch with white mustard. The seeding rate of mustard seeds is 6–8 kg/ha.

When spring vetch is sown for seed in pure stand, the seeding rate is 2–2.5 million/ha, or 120–130 kg/ha; however, in pure stands seed harvesting is difficult.

Sowing is carried out at the earliest dates.

In sowings, pre-emergence herbicides Prometrin and Gesagard may be used to control weeds.

Harvesting begins when seeds in pods of the lower and middle tiers reach the wax ripeness stage. Seeds can ripen well in pods. Usually, two-phase harvesting is used, but in years with a dry second half of summer or when desiccants are used, direct combining is used.

Varieties

LOS 5 (1989).

Lgovskaya 31-292.

Kamalinskaya 611.

Nemchinovskaya 72.

Orlovskaya 88.

Lgovskaya 60.

Uzunovskaya 91.

Omichka 3 (1992).

Lgovskaya 22 (1993).

Uzunovskaya 91 (1995).

Vera (1996).

Lyudmila (1998). The variety was developed by the Research Institute of Agriculture of the Central Regions of the Non-Chernozem Zone (Moscow Oblast).

Nikolskaya (2004). Developed by the VNII of Legumes and Groat Crops (Oryol Oblast).

List of sources

1. Vavilov P. P., Gritsenko V. V., Kuznetsov V. S., et al. (1986). Crop Production. Ed. by Vavilov P. P. 5th ed., revised and enlarged. Moscow: Agropromizdat.
2. Kolomeichenko V. V. (2007). Crop Production/Textbook. Moscow: Agrobusinesscenter.
3. Niklyaev V. S. (2000). Fundamentals of Agricultural Production Technology. Agriculture and Crop Production. Moscow: Bylina.