化学除草剂在刺槐林改造更新中的应用技术研究

A Technique of Using Chemical Herbicides to Improve Black Locust Forests

１９９３～１９９４年，在渭北黄土高原刺槐改造更新幼林地，用４种化学除草剂对刺槐伐桩萌芽和林地杂草防除进行了研究。结果表明：刺槐伐桩萌条防除应在萌条未木质化阶段用低容量喷雾法施药、或在伐桩未萌芽阶段用涂抹法施药，但前者除萌效果最好。节约投资４０．４％～６７．９％，提高工效２．５～４．０倍。喷雾法最适药剂种类及有效剂量为：目的伐桩用１．４ｋｇ／万丛的革甘膦或０．３～０．５ｋｇ／万丛的森革净；非目的伐桩用１．２～３．０ｋｇ／万丛的２，４－Ｄ丁酯或２．１ｋｇ／万丛的革甘群。萌生刺槐分别与油松、华山松、落叶松、杜仲混交幼林地化学除草，应在４月底用有效剂量０．５ｋｇ／ｈｍ２的森草净或２．０ｋｇ／ｈｍ２的２，４－ＤＴ酯，或用０．８ｋｇ／ｈｍ２的革甘膦（杜仲除外）低容量喷雾。除草率达８３．２％～８７．６％，提高工效６０倍，节约投资３８．９％～６０．０％。

Four kinds of chemical herbicides were applied to black locust forests on Weibei loess plateau to see their effects on stump sprouts and weeds in the forests, the results show that the herbicides could be painted onto the stumps before sprouting or sprayed before the sprouts the latter was better than the former, the investment could be saved by 40. 4 %～67. 9% and working efficiency be raised to 2. 5～4. 0 times if the latter method were used. Herbicides and dosages suitable for the spraying methed are as follows: 1. 4kg glyphosate or 0.3～0. 5kg osto Per 10 000 stumps to remove unwanted sprouts; 1. 2～ 3. 0kg 2, 4 ─ D or 2. 1kg glyphosate per 10 000 stumps to remove all the sprouts. For weed control in mixed forests between black locust and chinese pine, armand pine, larch and eucommia osto (0. 5kg/hm2) or 2, 4 ─ D (2.0kg/hm2 ) or glyphosate (0. 8kg/hm2) (except for mixed forests of black locust and eucommia) should be sprayed at the end of April. The effectiveness was 83. 2%～87. 6%, working efficieing could be raised to 60 times, investment could be saved by 38. 9 %─60. 0%.