论文部分内容阅读
沙兰杨(Populus×curamericana cv.‘Sacrau~(79)’),1978年大量引进我市,经在渠、路、“四旁”栽植,生长良好。1980年春在武清县城关公社草茨大队村西沙土耕地上,采取林粮(油)间种形式,营造了15亩小片丰产林,进行试验。一、试验目的及要求 1.利用条件较好的耕地,实行大行距林粮(油)间种,集约经营,造林后三年内粮油作物不减产,后两年产量顶一年,五年长成
Populus × curamericana cv. ’Sacrau ~ (79)’), a large number of imported in 1978 in our city, by the canal, road, “all around” planted well. The spring of 1980 in Wuqing County Chengguan commune sowing grassland team Xisha soil cultivated land, to take Lin grain (oil) species in the form of 15 acres to create a small piece of high yield forest for testing. I. Objectives and requirements of the trial 1. Utilize the cultivated land with better conditions to implement the planting of trees and grain (oil) at a large distance from each other and operate intensively. After three years of afforestation, the output of grain and oil crops will not decrease, and the output of the latter two years will top for one year and grow into five years