Gardening Articles: Landscaping :: Trees, Shrubs, & Vines
Garden Guru: Whitney Cranshaw (page 2 of 2)
by Cathy Cromell
Cranshaw is researching plant varieties resistant to this pest, the potato (tomato) psyllid, which injects a toxin that has insidious effects on plants. It's what inspired him to write Pests of the West.
This summer Cranshaw is helping gardeners with myriad insect problems brought on by the drought. Trees and shrubs are stressed, and as a result they are more susceptible to attack by borers and bark beetles. Thrips are usually controlled by rain, which traps nonfeeding pupa stages of the insect in the soil, but the drought has allowed them to thrive. Spider mites also are frolicking in the dusty soil, and dry lawns are more welcoming to chinch bugs, largely because their natural enemies are inhibited by the arid conditions. Honeydew from aphids and soft scales is building up in tremendous amounts on some plants because there's no rainfall to wash it off.
"Also, in isolated areas we are seeing a bit of an 'oasis effect' where the irrigated landscapes concentrate the activity of insects," says Cranshaw. In these areas flea beetles and leafcutter bees are having a heyday.
He also forecasts a big yellow jacket year. The lack of rainfall has allowed good nesting sites, and the high temperatures have accelerated population growth. "They'll run out of food in August and get grumpy," he predicts. "I'll be receiving a lot of calls."
When Cranshaw isn't conducting pest management research, teaching, or working with the public through the Cooperative Extension Service, he squeezes in time for writing. He's now working on a new book, Garden Insects of North America, to be published by Princeton University.