Wednesday, July 11, 2012

Western Tarnished Plant Bug

Western Tarnished Plant Bug (Lygus lineolaris)
(c) John Ashley
Western Tarnished Plant Bug
You'd think that a bug decorated with a big heart would be endearing to normal people (which excludes entomologists). But the western tarnished plant bug (Lygus lineolaris) feels no love from our species.

That's because this little native insect has a big menu, feeding on at least 385 different host plants. Fruit crops like apples and cherries, garden vegetables like potatoes and spinach, and popular flowers like marigolds and chrysanthemums. People like all of these plants better than they like bugs - even cute bugs with little green hearts.

Here in western Montana, the tarnished plant bugs also feed on many of our native conifer trees, including larch, Douglas fir, lodgepole pine and white spruce. Using their needle-sharp mouth parts, they simultaneously suck up plant juices while injecting saliva into the plant to hasten digestion.

Western Tarnished Plant Bug
on thistle bloom (c) John AshleyTheir singly-laid eggs hatch after 7-10 days, and the nymphs go through five instars before turning into adults. This life cycle takes 3-4 weeks to complete, and there are 2-3 generations each year. The heart-decorated adults peak in number during early July, early August and early September. To look for them, simply search about 385 different plant species. And when you find one, have a heart and don't squish him - unless he's in your orchard, garden or flower bed.