调查害虫对牧草产量影响的最直接方法是用化学药剂控制并测定其对产量的影响。多数已发表的害虫造成损失的估计都是用这种方法。使用杀虫剂后的产量评估避开放牧,而是间断地机械收割,这样做经济易行并可避免牲口取食残留毒素的危险。 但是在英国,约有70％的草地用来放牧而不是收割。有证据表明,至少有几种草地害虫——为害茎杆的双翅目昆虫,尤其是麦杆蝇(Oscinlella spp.),其密度在放牧的草地比在相似的机械收割的草地高。该试验 The most direct way to investigate the effects of pests on pasture yields is to control them with chemicals and determine their effect on yields. Most published pests cause damage estimates using this method. The assessment of yield after insecticide use avoids grazing and intermittently harvests it mechanically, making it economically viable and avoiding the danger of the animal feeding residual toxins. But in the United Kingdom, about 70% of the grassland is used for grazing instead of harvesting. There is evidence that at least several grassland pests, dipteran-stinging Diptera, especially Oscillatus spp., Are more densely grazed than grass on similar mechanically harvested grasses. This test