Methods to improve degraded grass stands of crested wheatgrass (Agropyron pectiniforme) in northern-eastern steppe zone of Kazakhstan

Altinay Kukusheva, Zibagul Kakezhanova, Uakhitov Zhastlek, Sarbasov Ardager, Beybit Nasiyev

Abstract: The article provides information on the study of the impact of surface treatment with mechanized tools on degraded grass stands of crested wheatgrass (Agropyron pectiniforme) in the arid climate of Northeast Kazakhstan. Due to the extensive root system, wheatgrass, in a short time, forms a solid sod layer; at the same time, from year to year, grass density increases several times, reducing the feeding area of wheatgrass to a minimum and, as a consequence, the fresh yield decreases. Grass stand of wheatgrass can remain in one locality for more than 10-20 years. The longevity of the wheatgrass is explained by its high drought and winter hardiness and good vegetative and seed regeneration of the herbage. Moreover, the stubble residues of perennial wheatgrass greatly enrich the soil with humus. According to the data obtained, mechanized tillage reduced soil density, improving its water permeability and increasing the productive moisture reserves in the soil (by 5.6-18.6 mm). As well as, mechanized tillage influenced the nutrient and air regimes by destroying the dense sod layer, loosening the soil, and creating an optimal feeding area for plants, increasing, in their turn, the yearly grass density by 12-37 pcs/m2. These methods had a positive impact not only on soil indicators but also on the fresh yield of wheatgrass: when using soil spiker and disc harrow, it averaged for two years 1.76 and 1.85 t/ha, respectively; when using heavy disc harrow – 2.81 t/ha and 2.59 t/ha, compared with the control – 0.82 t/ha.

Keywords: crested wheatgrass (Agropyron pectiniforme); degraded crops; fresh yield and hay yield; soil fertility; tillage

Date published: 2023-10-23