(四)田园管理的改良。这方面包括田园清洁、中耕、追肥、灌溉、排水、果树的修剪等。 田园清洁首先要求清除作物的各种残余物,如遗株(茬)、枯枝、落叶、落果等,因为在这些残余物中往往潜藏着不少的害虫,在冬季更常常是某些害虫的越冬场所。例如,水稻椿中往往有大量越冬的螟虫;谷茬中往往有大量的 (D) pastoral management improvement. This includes pastoral cleaning, cultivation, top dressing, irrigation, drainage, fruit tree pruning and so on. Pastoral cleaning first requires the removal of various residues of crops, such as plant (stubble), dead branches, deciduous leaves, fruit drop, etc., because these residues are often lurking a lot of pests in winter is more often some pests Winter place. For example, rice piles tend to have a large number of wintering stem borers; stubble often has a large amount of