Plum Trees In Puget Sound Area Susceptible To Diseases, Insects

Q: My Italian prune tree always seems to have fruit and leaf problems. Can anything be done for it?

A: Plums and other stone fruit are susceptible to several diseases and insects in our area. The brown-rot fungus organism can attack and kill blossoms and branches in spring and rot the fruit in the latter stages of its development. Properly timed sprays containing a proven fungicide may be necessary. Bacterial canker is another disease that can kill branches and even entire trees.

Insects, namely aphids, scales and leafrollers can be pretty devastating and may also need to be controlled, using appropriate insecticides. It would be helpful for you to have WSU's Spray Guide for Stone Fruit. Send 50 cents and a long, self-addressed, stamped envelope to WSU Extension, 612 Smith Tower, Seattle, WA 98104. Ask for EB 918.

Q: What can I do without hurting my pets to control root weevils eating my rhododendrons?

A: Several options are available. Go out at night with a flashlight and pick them off the foliage. Spread a tarp under an infested rhody and after dark go out and shake it. The weevils will all fall onto the tarp and can be drowned in a bucket of soapy water. Some folks have been successful using Tanglefoot around the base of shrub stems to prevent the flightless weevils from climbing up into the plants at night to feed.

Orthene is an insecticide that will control root weevils. Make sure your pets are not present when applying it. Once it's dry, it should not be a problem for cats or dogs. A new insecticide derived from the tropical neem tree shows promise for the control of root weevils. It is not likely to be available locally yet but a mail order source does have it. Write to the Ringer Corporation, 9959 Valley View Road, Eden Prairie, MN 55344 for more information.

Q: How do I get rid of moss in my lawn?

A: This question keeps reoccurring like a bad dream. Moss is a fact of life in our region. Full sun, well-drained soil, thatch-free turf, appropriate irrigation and fertilization, plus recommended grass species all can help to produce a nice, thick lawn that should be more resistant to moss and weed invasion.

Ferrous or ferric sulfate applied to moss will kill it, but it'll keep coming back if the recommendations above are not followed. Lime will not have significant effect in controlling moss growth.

For more information on lawn care call 296-DIAL and ask for tape 1523 "Fertilizing and Mowing."

Gardening runs Friday in Scene and Sunday in Home/Real Estate. It is prepared by George Pinyuh and Holly Kennell, Washington State University/King County Cooperative Extension agents, Mary Robson, Master Gardener program assistant, and volunteer Master Gardeners.