Broad‐leaved dock (Rumex obtusifolius L.) is a troublesome weed that predominantly grows in pastures and grassland. We hypothesised that frequent defoliation of Rumex will, over time, result in a reduction in root weight and leaf area, to the point where the impact on grass production is negligible. In order to investigate this hypothesis, we conducted three experiments. The objective of the first experiment was to perform a preliminary test of the hypothesis, using potted plants growing in the controlled conditions of a glasshouse. This experiment showed a rapid decline in leaf growth in plants that were defoliated weekly. The objective of the second experiment was to test the hypothesis in realistic outdoor conditions while still being able to collect detailed plant growth information. This experiment confirmed the findings of the glasshouse experiment and provided evidence that leaf growth ceased as a result of a dwindling supply of carbohydrate reserves in the root. Defoliated plants did not exhibit increased mortality. Finally, the objective of the third experiment was to test the hypothesis in a commercial pasture where normal field operations, specifically grass harvesting (three times) and slurry injection (twice), were performed. The results of this experiment were consistent with the results of the other two experiments. We conclude that weekly defoliation, maintained for three or more months, is an effective method to control (reduce the impact on grass production), but not kill, R. obtusifolius in pasture.

中文翻译：

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每周落叶控制，但不杀死阔叶坞（Rumex obtusifolius）

阔叶草 (Rumex obtusifolius L.) 是一种麻烦的杂草，主要生长在牧场和草原上。我们假设，随着时间的推移，Rumex 的频繁落叶会导致根重和叶面积减少，以至于对草产量的影响可以忽略不计。为了研究这个假设，我们进行了三个实验。第一个实验的目的是对假设进行初步测试，使用在温室受控条件下生长的盆栽植物。该实验表明，每周落叶的植物的叶子生长迅速下降。第二个实验的目的是在真实的室外条件下测试假设，同时仍然能够收集详细的植物生长信息。该实验证实了温室实验的结果，并提供了证据表明，由于根中碳水化合物储备的供应减少，叶子生长停止。落叶植物没有表现出死亡率增加。最后，第三个实验的目的是在一个商业牧场中测试假设，在那里进行正常的田间操作，特别是割草（三次）和浆液注入（两次）。本实验的结果与另外两个实验的结果一致。我们得出的结论是，每周脱叶，维持三个月或更长时间，是控制（减少对草产量的影响）而不是杀死牧场中的 R. obtusifolius 的有效方法。