A new study says a 【 1 】 insecticide is damaging wild bee 【 2 】 . Wild bees are important, because they pollinate 【 3 】 and wild plants. Environmentalists in the United States and 【 4 】 say this insecticide is causing a 【 5 】 in the number of bees. These insecticides are among the most commonly-used 【 6 】 . Farmers often use seeds 【 7 】 with the insecticides. The chemicals 【 8 】 insects that eat crops, and they do not 【 9 】 beyond the field. But they do get into pollen and nectar, which is where the bees come into 【 10 】 with them. Researchers 【 11 】 bees in fields. They say there were about half as many wild bees per 【 12 】 meter in treated fields as in 【 13 】 ones. Using the chemicals too much may be hurting bees. They suggest that the chemicals should be used more 【 14 】 , or, in other words, only when 【 15 】 .