Friday, May 1, 2015

Four-lined plant bug

Have you seen me?  Not me, as in me, Wizzie, but me as in me, this bug.  We have them in the demonstration garden and I've been getting reports of them from all over town.  Some people have seen damage, which is often mistaken for fungal damage. I suggest that you head out to the yard and start looking.

Four-lined plant bug with damage.
Four-lined plant bugs are brightly colored.  Nymphs (immatures) are red while older nymphs start to have wing pads with yellow and black stripes.  Adults have fully developed wings that are yellow and black striped.  Adults look similar to- and may be mistaken for- striped cucumber beetles.

These insects have piercing-sucking mouthparts they use to suck out plant juices.  The plant bugs suck out chlorophyll and leave a "window" between the upper and lower epidermis of the leaf. Damage appears as white, dark or translucent spots of foliage.  Feeding may also cause curling and browning.  Fortunately, damage is mostly cosmetic, but if you are trying to eat the foliage of the damaged plant it may become a problem.

The insects feed on a wide variety of hosts, including fruits and vegetables, annuals and perennials and  woody plants.  When disturbed, the insects are fairly good at hiding.  They either crawl to the underside of the leaves or drop to the ground to hide among foliage.

If you feel the need to manage these guys and gals, try insecticidal soap.  If that doesn't work, you can try azadirachtin (neem- concentrate, not oil; it's getting too hot to use oil formulations) or pyrethrins.  If that doesn't work then try a residual contact product.

1 comment:

Donut Army said...

Thanks for this! I've been Facebooking pictures of these bugs to some other gardeners I know.