Four Lined Plant Bug - "Dr. Z's" Tip of the Week

The Four Lined Plant Bug is a beetle-like insect of the late spring and early summer.  They are only destructive when they build up in large numbers, otherwise they are usually not a problem since they appear and then disappear out of the picture quickly.  Most gardeners  notice the damage after the insect has left.  Therefore control measures are rarely needed since they do not pose a threat to the overall health of the host plant.
Generally they attack herbaceous perennials (Chrysanthemum, Shasta Daisy, Rudbeckia, Nepeta), certain shrubs (Hydrangea, Forsythia, Mock Orange, Viburnum, Dogwood), and herbs (Mint, Basil) among others.
The damage is the result of both the baby nymphs and adults feeding.  They insert their needle-like mouth parts into the upper surface of the leaf to feed and suck out the chlorophyll.  This creates a series of tan, brown ,or black round spots in a random pattern over the leaf when they move around to feed.  Damage is usually concentrated on the upper areas of the plant. There is only one generation of Four Lined Plant Bugs per year.
Cutting down (when possible) and removing all debris at the seasons' end will help with control since the eggs are laid in the host plants' stems for the following year.  If the infestation is severe and a lot of damage is occurring, spray the plant material with Neem Oil.

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