Combination schemes of grass species in high density dwarf rootstock apple orchard in Guanzhong area

The popularization of high-density dwarf rootstock apple planting technology provides a good development opportunity for its application to orchard grass technology. However, it simultaneously is associated with higher requirements for the standardization of orchard grass technology application. Generally, it is difficult, using single-seeded grass species, to meet the requirements for modern management in apple orchards. In this experiment, the growth characteristics of five different combination schemes of grass species were compared and evaluated in a high-density dwarf rootstock apple orchard in Guanzhong area. The combination scheme of tall fescue (70%) + kentucky bluegrass (20%) + perennial ryegrass (10%) not only had faster seedling emergence and a longer green period, but also had excellent flatness, which was highly suitable for mechanical operation. The combination scheme of tall fescue (30%) + perennial ryegrass (30%) + cocksfoot (20%) + kentucky bluegrass (20%) had fast seedling emergence, good reproducibility, a medium green period, and good persistence. This scheme satisfied the requirements for artificial management, and was also an ideal combination scheme in Guanzhong area. The combination scheme of white clover (50%) + cocksfoot (20%) + perennial ryegrass (30%) had good persistence and increased the proportion of white clover in the grassland population year by year, with the proportion increasing to more than 50% in the third year. The grass can be used for silage or forage feeding livestock after mowing, which also makes this an ideal combination scheme in Guanzhong area.