A Study on the Control Measures of the Withering of Young Pinus sylverstris var.mongolica

Chemical control measures on the diseased young forest of Pinus sylvertris var.mangolica in Yulin sandy area were established by the insecticide efficacy determination,field experiments,investigation of forest management,and experiment of integrated control measures.The lightly diseased forest could be controlled by Mancozeb(50%WP,diluted,400times) or Thiophanate-methyl(70%WP,diluted,400times) twice,the severely diseased forests could be controlled twice by the chemical insecticide on the basis of cleaning up the deadwood in the forest land.Mixed forest should be planted,the density should be above 2 m×3 m to afforest.Afforestion of P.sylverstris var.mongolica was unsuitable on lower and subsidiary dunes.