Sainfoin

Economic importance

Sainfoin hay is similar in nutritional quality to alfalfa hay. When green mass is fed to cattle, it does not cause bloat when grazing on dew or in rainy weather.

100 kg of sainfoin hay correspond to 54 feed units and contain 12.6 kg of digestible protein; 100 kg of fresh grass — 24.8 feed units and 3.9 kg of digestible protein (RI of Feed).

Sainfoin has agronomic importance as a good preceding crop in crop rotation. The yield of winter wheat after fallow occupied by sainfoin, averaged over 9 years, was 2.7 t/ha of grain, second only to black fallow by 0.2 t/ha (Kharkov Agricultural Institute). It serves as a good fallow-occupying crop, releasing fields early, and also for sodding sloping lands and sandy soils.

Also, like other leguminous plants, sainfoin, owing to its ability for nitrogen fixation, enriches the soil with nitrogen, accumulating up to 100-200 kg/ha and 5-6 t/ha of plant residues.

Honey plant.

History of cultivation

Sainfoin began to be cultivated in Transcaucasia in the 10th century (according to other data, in the 5th century), in southern France at the end of the 15th century, and in Russia in the early 19th century.

Yield

Hay yield can vary from 2.5 to 6 t/ha.

In many regions of the steppe and forest-steppe zones, sainfoin produces high hay yields. Under low-water irrigation, sainfoin hay yield is 20-25% higher than that of alfalfa. Thus, at the Altai Research Institute of Agriculture, the average hay yield of sainfoin over 11 years was 5.3 t/ha. At the Kostanay variety trial plot, the hay yield of a grass mixture including sainfoin was 5.6 t/ha.

In Belgorod Oblast, hay yield was 5.4-5.7 t/ha.

In a soil-protective crop rotation, a mixture of Transcaucasian sainfoin and smooth brome gave 60 t/ha of green mass over 3 years of use. Sainfoin in mixture with smooth brome shows high yield in forage crop rotations of the steppe zone.

In addition, it is distinguished by high seed yield of up to 0.7-0.9 t/ha.

Botanical description

The root system is taprooted, penetrating the soil to a depth of up to 1 m, on loose soils up to 2-2.5 m (maximum up to 4-5 m); the main mass of roots is concentrated at a depth of up to 20 cm. It has the ability to use sparingly soluble calcareous and phosphorus compounds, therefore the application of phosphorus fertilizers almost does not increase hay or seed yield.

The leaf is compound, odd-pinnate, with 6-18 pairs of leaflets and one terminal leaflet; the lower leaf is on a long petiole.

The stem usually does not branch. From each node a leaf with two stipules is formed. Plant height is from 80 to 100 cm.

The inflorescence is a spike-like raceme 3-20 cm long.

The flowers are large, pink, sometimes white or red, with dark stripes. Cross-pollination is by insects.

The fruit is a single-seeded bean of rounded shape, hairy, 6-9 mm long; the valves are firmly joined, therefore sainfoin is sown with beans, usually called seeds (seed pods).

Species

Sainfoin includes over 150 species. The following have become widespread in cultivation: common, sand, and Transcaucasian.

Common sainfoin (Onobrychis viciifolia Scop), or ordinary, or cultivated — a short-lived plant. Height under natural conditions is 30-60 cm, in cultivation 70-150 cm. Number of internodes is 5-7. The leaf is elliptical, sometimes lanceolate, dark green. The raceme is ovate. The flower is pink with a red tinge. Beans are large, 1000 weight 17-22 g. It is grown in the steppe and forest-steppe zones of Russia, in particular in the Central Chernozem zone.

Sand sainfoin (Onobrychis arenaria D.C.), or wild — a mid-season plant. Height in natural phytocoenoses is 30-50 cm, in cultivation 50-100 cm, sometimes 125 cm. The root system is powerful, penetrating the soil to a depth of 1.7 m; it absorbs sparingly soluble nutrients more strongly than other sainfoin species. The bush is erect. Number of internodes is 6-8. The stem is coarse. The leaf is lanceolate, green; in upper leaves yellow-green. Lower leaves are on long petioles, upper leaves on short ones. The raceme is mouse-tail-shaped, narrow, pointed. Flowers are violet-pink, with dark stripes. Beans are small, smooth, slightly shiny, grayish-yellow-green, 1000 weight 11-15 g. It is distinguished by frost resistance. In forage and field crop rotations it is usually used for hay and grazing on aftermath. It is grown in the Volga region, North Caucasus, and Western Siberia.

Transcaucasian sainfoin (Onobrychis antasiatica Khin), or Caucasian, or Western Asian. Young shoots and leaves are pubescent, gray-green. The stem is hollow and tender. The raceme is long, cylindrical, with a blunt apex. Beans are shortly pubescent, less often glabrous. 1000 weight is 15-20 g. Hard seed content is 10-20%. In yield it surpasses other species, as well as alfalfa. It produces 2 cuts per year; seeds ripen in the year of sowing. It is more productive than cultivated sainfoin, regrows faster, giving two cuts, therefore it is also called two-cut. It is distributed in the North Caucasus and the Central Chernozem zone.

Unlike alfalfa, all sainfoin species are less damaged by pests and diseases, giving stable seed yields of 600-800 kg/ha.

Ecological requirements

Plant nutrition

From 1 t of sainfoin hay, 6-7 kg/ha of P₂O₅, 18-20 kg/ha of K₂O, 11-12 kg/ha of calcium, and 1.5-1.7 kg/ha of magnesium are removed from the soil.

Owing to its powerful root system and its ability to assimilate phosphorus from sparingly soluble compounds, the effect of fertilizer application appears only before the root system begins to form. At the same time, sainfoin significantly increases the use of phosphorus fertilizers by the following crop.

Vegetation

Sainfoin has spring (early) and winter (late) types of development; for sand and Transcaucasian sainfoin the spring type predominates, while for cultivated sainfoin the winter type does.

After the cotyledons appear, the first single-leaflet true leaf appears, then the second and third with three leaflets. The number of pairs of leaflets on each subsequent leaf increases. In the axils of the lower leaves, lateral buds are laid, located above the place of attachment of the cotyledons, as a result of which the tillering zone is a kind of head or crown. After 10-14 days after emergence, it is gradually drawn into the soil. This process is especially intensive in sand sainfoin. Thus, 3 months after emergence, the head of common sainfoin was at a depth of 1.9 cm, while in sand sainfoin — 2.2 cm. In the subsequent 2nd and 3rd years of life, the head continues to sink into the soil, but at a lower rate.

In the first month of vegetation, the formation and deepening of the root system is most intensive; on the 20th day after emergence, the length of the root system exceeds plant height by 3-4 times.

Winter forms form a sprawling rosette of leaves, spring forms — a more compact and elevated one. In dense sowing, the number of leaves is 15-20; in sparse sowing — 36-50. The number of leaflets on the uppermost leaves can reach 19.

The regrowth phase in all sainfoin species begins earlier than in alfalfa. The period from regrowth to the beginning of flowering is 60-65 days; to seed ripening — 110-120 days. In autumn, sainfoin stops active growth when the average daily temperature falls below 5 °C.

Flowering begins 7-14 days earlier than in alfalfa.

By the end of vegetation, with coverless sowing in early spring, the spring type of sainfoin usually reaches the stem elongation phase — beginning of flowering; sometimes plants can form seeds. Plants of the winter type finish vegetation in the leaf rosette phase.

Under the cover of another crop in the first year of life, sainfoin grows slowly, managing to form only a rosette of basal leaves by autumn. It reaches full development in the second year of life. High yields of dry mass and seeds occur in the second and third years; in the fourth and fifth years, stands thin out and die off, but under favorable conditions it can persist in grass stands for up to 6-8 years.

Sand sainfoin tolerates continuous livestock grazing fairly well; regulated grazing on aftermath after cutting is allowed. Its aftermath capacity is poor, because after mowing regrowth occurs slowly, and only rosettes of basal leaves are formed. Common sainfoin and some forms of Transcaucasian sainfoin better withstand grazing, therefore they can be included in pasture grass mixtures, but grazing is not allowed in the year of sowing. With early first grazing, it can produce another 1-2 aftermath growths. In pasture it is satisfactorily eaten by various animals; in autumn — less readily than alfalfa.

Crop rotation

Sainfoin can be cultivated in field, forage, and soil-protective crop rotations. Various crops can serve as predecessors.

In field crop rotations, winter wheat and maize for green fodder are considered good predecessors; in forage rotations — cereal crops, forage root crops, and other crops.

When sodding slopes, sainfoin is sown without cover in grass mixtures with grasses (Poaceae) and legumes.

When used for one year in occupied fallow, sainfoin is usually sown in pure stand.

Fertilizer

At sowing, row fertilizer with granulated superphosphate is used; when applied at 50 kg/ha it increases hay yield by 0.5-0.6 t/ha (ARRI of Grain Economy).

Application of 200 kg/ha of superphosphate under plowing in Moldova increased hay yield by 0.4 t/ha.

Other fertilizers are generally not applied to sainfoin, except on very poor soils.

Soil treatment

After harvesting the predecessor, stubble cultivation is carried out to 5-7 cm. When fields are infested with root-sprouting weeds, it is better to carry out cultivation with share cultivators to a depth of 10-12 cm. With a large spread of root-sprouting weeds, repeat cultivation is done 2-3 weeks after the first, and then deep plowing to a depth of 20-25 cm.

In arid and semi-arid conditions, leveled fallow is used, i.e., after autumn plowing the field is cultivated and harrowed so that spring pre-sowing soil treatment is reduced to harrowing and sowing to minimize moisture loss.

Sainfoin responds well to deepening of the arable layer to 25-27 cm.

Sowing

On the day of sowing, seeds are treated with bacterial preparations, for example, nitragin, which increases hay yield by 0.5-0.6 t/ha. Even greater efficiency is given by combined treatment of seeds with bacterial preparations and molybdenum microfertilizers at the rate of 200 g of ammonium molybdate per hectare sowing norm. According to data of ARRI of Feed, treatment with molybdenum microfertilizers and nitragin increased sainfoin hay yield by 0.9 t/ha.

For seed dressing against ascochyta blight, seed mold, anthracnose, fusarium, white and gray rots, TMTD preparations are used 2-15 days before sowing.

Before sowing, seeds are cleaned of impurities, primarily from seeds of burnet, which reduces yield.

Sainfoin is usually undersown under the cover of spring grain crops. Sowing is carried out early, in the first 2-3 days from the start of field work. Since sainfoin seeds are quite large compared to other perennial grasses, it can be sown in a mixture with grain seeds, or by the inter-row method with grain-grass seeders. When undersowing under winter crops, sowing is carried out with disk seeders across the rows of the cover crop.

For late sowing dates, millet can serve as a cover crop in the steppe zone. For summer coverless sowings, sainfoin is sown from July 20 to August 10. Freshly harvested seeds are suitable for summer sowing, since their post-harvest ripening is 8-10 days with air-thermal heating.

The total recommended seeding rate of seeds in pure stand in forest-steppe, foothill regions, and irrigated lands is 90-100 kg/ha; in steppe — 70-80 kg/ha. For sand sainfoin in the steppe zone in pure sowing — 50-60 kg/ha; in forest-steppe — 70-80 kg/ha. For common sainfoin in the steppe zone — 60-75 kg/ha; in forest-steppe — 90 kg/ha. In grass mixtures — 35-40 kg/ha.

Sowing depth on heavy soils is 3-4 cm; on light soils — 4-6 cm.

Crop care

When harvesting the cover crop, straw is immediately removed from the fields, leaving stubble 15-20 cm high, to protect young sainfoin seedlings from sunburn and, in winter, to accumulate snow.

In spring of the next year, harrowing in two passes is performed to remove stubble and loosen the topsoil. After cutting for hay, the field is harrowed with heavy harrows.

In arid regions and on sloping lands, it is recommended to carry out autumn slotting on second- or third-year sainfoin stands for additional moisture accumulation in the soil. Slotting is done with PRVN-2.5A chisel plows equipped with slot cutters.

Against annual grass and dicotyledonous weeds, pre-sowing herbicides Treflan and Triflurex are used.

Diseases

Characteristic diseases of sainfoin include:

• powdery mildew, which affects leaves, stems, and beans. With severe development of the disease, seed yield decreases by 50-70%;
• rust, affecting leaves, stems, peduncles, and beans. It is dangerous in the early period of plant development; it more often spreads on old-aged stands and reduces hay and seed yield;
• fusarium; with severe damage, only brown stems remain on plants. Some Fusarium species can affect the root, leading to rot. With severe development of the fungus, mass death of plants occurs.

For disease control, early mowing of affected stands is carried out, post-harvest plant residues are destroyed; for seed purposes, seeds obtained from less infected stands are used; crop rotation is used; new sowings are placed away from old-aged ones; resistant varieties are introduced.

Pests

The sainfoin seed beetle attacks the bean and seeds. Hatched larvae gnaw through the walls of the bean and eat out the contents of the seed. Seed damage can reach 30-50%.

The sainfoin eurytoma lays eggs in the seed flesh. Larvae hatched from the eggs eat out the contents of the seed.

For pest control, seeds are cleaned, since damaged seeds are lighter than healthy ones and are easily separated on grain-cleaning machines. Rejected damaged seeds are burned.

Chemical control agents — Carbophos, Carbophot, Fufanon, Kemifos, Bunchuk. Spraying is carried out during vegetation.

Seed crops of sainfoin are damaged by the sainfoin flower midge, sainfoin flower beetle, and sainfoin thrips. Against these pests, approved chemical preparations are used. To reduce the harmful effect of nodule weevils, seeds are treated before sowing with molybdenum microfertilizers and bacterial preparations; sowing is carried out early; new sowings are placed away from old ones.

Harvesting

Mowing sainfoin for hay begins in the budding — beginning of flowering phase, finishing by the mass flowering phase. Delay in harvesting leads to a decrease in protein content by 15-20%; the hay becomes coarse and is poorly eaten by animals. In addition, mowing during full flowering almost does not produce aftermath.

Cutting height is 6 cm from the soil surface. The last cut is made at a height of 8-10 cm for sufficient accumulation of plastic substances by plants before winter, better snow retention, and better regrowth in spring. Otherwise, hay harvesting technology is similar to hay harvesting of other leguminous grasses.

Growing for seed

In a humid zone, sainfoin seed stands are allocated in ordinary sowings of the second year of use, first cut. In arid regions and with a shortage of seeds, seed stands are sown in summer on clean fallow; usually such sowings are more productive than early spring undersown ones. In the Lower Volga region, North Caucasus, and southern Ukraine, it is recommended to sow seed stands on clean fallow from August 15 to 20; in the northern part of the forest belt of Ukraine — no later than August 5; in the forest-steppe zone and Middle Volga — no later than August 1. The sowing method is ordinary row and wide-row (for faster propagation of promising varieties) with row spacing of 45-70 cm. The seeding rate is reduced by 2-3 times compared with ordinary sowing.

On ordinary row sowings, care of seed crops is the same as for forage crops; on wide-row sowings, 2-3 inter-row cultivations are carried out. For better pollination, apiaries are brought to seed stands, due to which seed yield increases by 100-200 kg/ha.

Ripe fruits shatter easily. Fully formed but green fruits ripen fairly well in swaths. However, in wet weather seeds can easily germinate. Separate harvesting or direct combining is chosen depending on weather conditions, technical capability, and weed infestation of crops.

Seed harvesting is more often done by the separate method. It begins when 40-50% of beans turn brown. First plants are mowed, laying the mass in swaths; after it dries, the beans are threshed.

Direct combining begins no later than browning of 70-75% of beans, finishing harvest in 2-3 days. After harvesting, the heap is immediately passed through winnowers, and the seeds are dried. In steppe and dry-steppe regions with hot summers, winnowed seeds are spread in a layer of 8-10 cm and periodically stirred. After that, sainfoin seeds are suitable for long-term storage provided their moisture content is not more than 14-15%.

Varieties

References

1. Vavilov P. P., Gritsenko V. V., Kuznetsov V. S. et al. (1986). Crop Production. Edited 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.