Hayfield

Hayfield 

land covered with grassy vegetation that is regularly mowed for hay, haylage, grass meal, silage, or green dressing. Hayfields may be either natural or cultivated. Cultivated hayfields are established in feed, field, and other crop rotations; plantings of perennial and annual grasses may be established outside a crop-rotation system. Annual grasses are used for one growing season, whereas perennial grasses are used for two or three years in field rotations, five to seven years in feed rotations, and ten or more years without crop rotation.

In 1974 the USSR had, on all types of farms, 45 million hectares (ha) of natural hayfields. Of this total roughly 70 percent was in the RSFSR, about 15.5 percent in Kazakhstan, 5 percent in the Ukraine, and 4 percent in Byelorussia. Small areas were occupied by hayfields in Moldavia, Turkmenia, and Tadzhiki-stan. Natural hayfields are divided into three basic types: flooded, or floodplain (roughly 20 percent); low-lying, or swampy (roughly 13 percent); and dry (roughly 67 percent).

Flooded natural hayfields are the best. Cereal-forb meadows are said to be short- or long-flooded, depending on the duration of the flooding period. The average yield for two cuttings is 20–25 quintals per hectare (ha) of good-quality hay; on some flooded meadows, for example, on the Oka, Iakhroma, and Ob’ river floodplains, the average yield reaches 60–80 quintals/ha. While occupying about 20 percent of the area of all hayfields, flooded meadows produce more than 50 percent of the gross hay harvest. Hay from flooded meadows has high nutritional value and good digestibility.

Low-lying hayfields occupy the flat part of watersheds with stagnant water; they are situated in minor depressions without outlets and in gulleys. Moisture is stable or temporarily excessive, flowing in or being supplied by groundwater. The yield consists of 12–15 quintals/ha of medium- and poor-quality hay; the hay is of low quality owing to the predominance of plants of the sedge family, which produce acidic feed.

Dry hayfields are located in dry valleys with temporary periods of abundant moisture. They are confined to typical dry valleys, flatlands without runoff, and minor depressions where surface waters stagnate in the spring and autumn. The stand of grass consists of a mixture of cereals, sedges, and forbs; the yield is 12–15 quintals/ha of good-quality hay. Typical dry valleys occupy an intermediate position between dry valleys with temporary periods of excessive moisture and absolutely dry valleys, which are primarily used as pasture. A typical dry valley has cereal-forb vegetation and some legumes; the yield is 8–12 quintals/ha of average- and good-quality hay.

Among the steps taken to improve natural hayfields, of particular importance is the systematic application of fertilizer, especially nitrogen fertilizer. Of all types of natural hayfields, flooded hayfields show the greatest gain in hay yield from nitrogen fertilizers. This gain is related to favorable moisture conditions and a good botanical composition of grasses. Phosphorus-potassium fertilizers promote the development of hayfields with legumes.

Other important procedures to preserve the productive longevity of natural hayfields include irrigation, snow retention, weed control, proper timing of first and subsequent mowings, and alternation of periods of crop rotation and combined use (hayfield and pasture). Varying the use of hayfields, for example, using the fields to obtain hay in the first year and for pasturing or planting in the second year, has a beneficial effect on productivity, rids large-stemmed weeds (for example, horse sorrel) from the fields, and makes it possible to restore the stand of grass. With combined use the hayfield may be used as pasturage at the end of the vegetative period. The grasses are cut for hay, haylage, or silage, and then the field is used for grazing livestock. Often only one type of hayfield is cultivated, making it ossible to manage the lands more efficiently and with lower labor expenditures.

Outside the USSR all natural feed lands are considered nonarable pasturelands, which, depending on the need of the farms, are used for grazing livestock or producing hay or for a combination of these purposes.

REFERENCE

Senokosy i pastbishcha. Edited by I. V. Larin. Moscow, 1969.

A. P. MOVSISIANTS