Chemical control of poisonous plants in Hongyuan natural grassland

To effectively control poisonous plants in the grassland,protect ecological balance and sustainable development of animal husbandry,chemical herbicides such as 2,4D butylate EC and Galium net (active ingredient was 20% fluroxypyr EC) were used to control some poisonous plants in Hongyuan natural grassland.The results showed that:(1) all poisonous plants appeared varying degrees of leaf distortion by spraying about 4 days;15 days later, aerial parts of some poisonous plants was found to have different degrees of death.(2) the control effects of both herbicides on Cerastium furcatum, Halenia corniculata and Thlaspi arvense were significant (100%),but it was not obviously on Potentilla bifurca; the control effects of Galium net on Taraxacum mongolicum,Geranium wilfordii and Polygonum sibiricum were higher significantly than 2,4D butylate EC.(3) The control effects of poisonous plants showed that highdose levels was significantly higher than lowdose levels,namely as 2,4D butylate EC (1 350 g/hm2),Galium net (1 012.5 mL/hm2)＞2,4D butylate EC (900 g/hm2), Galium net (675 mL/hm2).