Answer: Rhubarb is usually more or less pest free, and based on your description I'm not sure exactly what those beetles are. You might try rubbing/picking them off by hand, or washing them off with a firm spray from the garden hose. It's really important to identify exactly what is eating your plants before attempting to spray something on them. You may do more harm than good. My friend the entomologist is an "ant expert" and she says there are only a couple species of ants that actually eat plants. The more likely scenario is the ants are interested in the other insects on your plants. If the water spray doesn't work (you may have to do it daily to get things under control) you might wish to take a sample to your County Extension for a positive identification and suggested control, if any. Try to bring both insects as well as a sample of the damage. They are at 468 Rte. 13 S, Milford, 03055, 603-673-2510. Good luck!
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