The inhibition of the growth of perennial grasses by maleic hydrazide.

Abstract

The effects of spring and autumn applications of maleic hydrazide on Paspalurn dilatatum Poir, Sorghum hnlepense (L.) Pers., Paspalum distichurn L., and Phragmites cornrnunis Trin. at rates of 0.2-1.6 per cent. active material (2-16 lb/acre) are reported. Growth of all species was inhibited by the compound a t the higher dosage levels; the concentration required and the period of inhibition varied with species. In general the period of inhibition was longer in autumn than in spring applications. A stimulation of growth at lower dosages for both P. dilatatum and S. halepense was recorded. All treated S. halepense plants developed a secondary crown of adventitious roots on the first node. The possibility that maleic hydrazide and auxin are antagonistic is discussed briefly. The use of maleic hydrazide for the control rather than the eradication of channel bank weeds is discussed.