Though native to the Rocky Mountains, this pest long ago spread to all other parts of the United States except California and Nevada. The 3/8-inch long adult beetle is easy to spot: the showy polka-dot vest and striped pants are dead giveaways. The small, red-humped nymphs have articulated legs and rows of dark spots along both sides. Both adult beetles and nymphs denude plants, leaving black excrement as testament to their gluttony.
Target: Tomato-family vegetables and flowers.
Damage: Leaves and stems are chewed; whole plants may be devoured if the beetle population is large.
Life cycle: In spring, female beetles lay hundreds of elongated orange eggs in clusters on leaf undersides. About a week after egg laying, the larvae emerge and feed for a time, then burrow into the ground to pupate. The pupae can overwinter. There are one to three generations each year.
Notes: A thick mulch of straw or hay slows down the beetles.