COMPARATIVE EVALUATION OF DIFFERENT AGROTECHNICAL METHODS OF IMPROVEMENT (REJUVENATION) OF OLD AGE CROPS

Abstract

Rejuvenation of old-age grass by intensive loosening of the surface sod horizon of the soil has been carried out by many scientists, the standard methods of improvement for our arid, not windproof, soil conditions are unacceptable, so we explore such methods as the processing of grass stands of vetch with tooth harrows (Zig-Zag), processing with needle harrows (BIG-3), disc harrows (LDG-10), processing with heavy disc harrows (BD-5) and discator processing. Our practical goal was to use heavy discs to cut off the old roots of the Agropyron, creating better conditions for the regrowth of daughter roots and better aeration of the soil for optimal air access. Among many processing, the highest height of plants was in the variant with the processing with a disc (speed harrow) – 24 cm, which is more than the control by 3 cm, the negative effect on the height of plants was observed in the variant with tooth harrows (11 cm). After improvement, the density of grass has decreased on all variants of processing, especially at loosening by disk discs by     51.5 % and by needle harrows by 48.6 %. Because of the destruction of old shoots, as well as the appearance of new shoots, improved aeration, and an increase in the feeding area, the dry weight yield (hay) in all treated plots increased, except for the variant where the grass was processed with a tooth harrow, there is a decrease compared with control by 0.5 c/ha. The yield of the dry mass of Agropyron increased by 3.3 c/ha with processing by high-speed disc harrow, increased by 1.2 c/ha with needle harrow, by 0.9 c/ha with disc harrow, and by 0.4 c/ha with disc harrow in comparison with control. The best option was processing with a discator, because of the double row spherical discs with a certain angle, as well as the high-speed movement of the discs, compacted bushes of Agropyron clones are well broken into separate parts, especially last year’s bushes, according to our observations, the worst way to improve the old-age Agropyron crops is the processing with a tooth harrow, as heavy harrow discs because of the spherical shape destroy not only old stems but also pull out, cuts off the root system of Agropyron, and carries it to the soil surface, and the soil surface is dried up.