本省旱田殺草劑使用種類達四十餘種，其在環境中之殘留影響不容忽視。殺草劑在土中之殘留與其結構和環境因子有關。其中Urea及Triazine compounds皆屬殘留期較長之殺草劑。在食用作物中之殘留情形由於旱期施用，故非常輕微，不會對人體健康造成威脅。旱田殺草劑對魚之急毒害大都屬低毒性藥劑，影響不大。對短期輪作作物之影響則宜注意其施用藥劑殘留期長短與作物生長期之關係。殺草劑對地下水源之污染與其淋洗深度有關。土中微生物之活性大部分受殺草劑使用初期影響。果園殺草劑之使用則宜顧及水土保持之功能。

More than forty different herbicides are currently been used in the upland field which included vegetables, fruits, sorghum and maize. The reisual levels of herbicides in the soil was influenced by the soil structure and environmental conditions. Among the herbicides used, urea and triazine compounds have relative longer residual period. The residual level of herbicide in the edible part of crops were negligible beacuse most of the herbicides were applied during the early growing stage of crops. Only few of the herbicides used in upland crops were highly toxic to fish. Care must be taken not to pollute the rivers and fish ponds. Some herbicides may left over the soil and damage the next rotating crops. The polllution of under-ground water by the herbicides seems not very significant, because the leachy ability of upland used herbicides are very low. The effect of herbicides on the soil microorganisms might found right after application but not for prolong period. In the field of long term crops such as fruits orchard, atention have to be paid to the soil conservation.