Weed interference in Pinus radiata during the first two growing seasons

Abstract

To quantify the weed detrimental effect during the first two growing seasons, two field experiments were conducted at Portezuelo (72°24' Long W - 36°31' Lat S) and Pemuco (72°11' Long W - 36°58' Lat S). Also, the required weed control intensity and the accumulative effect of the two first years of weed control were determined. The pine plants' biomass index (D2H) decreased 65% when weeds were not controlled during the second year. A broad weed control programme was not necessary during the second year, being strip application of herbicides enough. When the area controlled was only equivalent to a "spotgun" application, pine plants grew as poorly as the ones in the weedy area during the second year.