There have been several reports of Mexican bean beetle attacking green beans. This insect is a bit unusual in that it is in the lady beetle (or lady bug) family, which we usually associate with insects that feed on other insects. In fact, lady bugs are a beneficial insect. However, this one feeds on bean leaves, so it is important to recognize this as a pest and not as a beneficial insect. Mexican bean beetles will feed on green beans, soybeans, and cowpeas.

Mexican bean beetle feeding occurs on the undersides of leaves. Damage is between the veins. The beetle only chews partway through leaves causing the leaf to look skeletonized.

This beetle looks a lot like a lady bug. Upon closer inspection, you will notice exactly 16 spots on its back. It is a bit larger than a regular lady bug. It is around a half of an inch long. Larvae are found on the bottom of leaves and look very different from that of a true lady bug. They are bright yellow with black-tipped yellow, branched spines. The larvae will also feed on leaves.

Leaves can withstand some damage before yields are effected. For garden beans, do not let them damage more than between 15 to 20 percent of the leaves.

To avoid these insects, plant beans as early as possible. As the season progresses, scout for this insect and crush them. If that makes you squeamish, then shake them off into a bucket of soapy water. If use of an insecticide is warranted, be sure to get good spray on the bottom of the leaves. 

For more information on the Mexican bean beetle, check out



Bagworms are becoming more visible on our trees and shrubs this time of year. These insects are small caterpillars that wrap themselves in pieces of the tree or shrub they inhabit.

Needless to say, they blend in with their surroundings very well. Their covering also protects them from any form of chemical control. In fact, chemical control will only be effective while the caterpillar is very small and has not yet covered itself. Because of their covering the only effective time of year to spray is June. The best thing to do this time of year is to pick them off the tree or shrub. 

For more information on bagworms, go to


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