Answer: It's really important to identify the pest before using any pesticide--"natural" or not. My first recommendation is always to try "cultural" methods first--pruning, weeding, thinning, cleaning up garden debris, etc. There are certain pesticides, like B.T., (a biological control) that target only one type of pest. Others, like horticultural oil, suffocate a variety of pests. Finally, there are "broad spectrum" controls, like pyrethrum and rotenone. These must be used with great caution, if used at all, because they will kill benefical insects as well as pests--and these beneficials can often keep pests in control by themselves!
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