Beet leafminers

Control Cover seedlings with floating row cover pick and destroy mined leaves and remove egg clusters remove nearby dock or lamb s-quarters, which are hosts for beet leafminers attract native parasitic wasps by planting nectar plants spray with neem or avermectins. 

Aldicarb is a systemic insecticide/acaricide/nematocide used against aphids, mites, Colorado potato beetles, thrips, boll weevils, leafhoppers, wireworms, leafminers, nematodes, and many others in citrus, cotton, ornamentals, peanuts, soybeans, sugar beets, sugar cane, tobacco, etc. Its oral LD50 in rats is 1 mg/kg. 

Beets, chard, nightshade family plants Leafminers... 

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