Rocky Mountains

August, 2004
Regional Report

Watch for Disappearing Tomato Leaves

Be on the watch for disappearing leaves and stems on your tomato plants. It can often happen overnight. The culprits are hornworms, large caterpillars with voracious appetites. Their green camouflage blends in with foliage and makes them difficult to spot. You can hand pick the worms and drop them in a bucket of soapy water. Or use a biological control -- Bacillus thuringiensis (Bt) -- which kills the caterpillars by infecting them with a fatal disease.

Pay Attention to Yellow Leaves

The sudden appearance of yellow leaves on newly transplanted trees and shrubs is often a good indication of stress to the root system. It may signal too much water and oxygen starvation, or soil compaction. Aerating the soil will help to alleviate the problem. Do not fertilize woody landscape plants now, since applications of nitrogen can stimulate late growth that is susceptible to an early fall freeze or winter injury.

Spray Wooley Aphids

If you observe an accumulation of white, fuzzy deposits on branches and pruning wounds of crab apple, hawthorn, cherry, and pear trees, you have an invasion of woolly aphids. These fascinating insects will produce a protective, white covering that renders insecticides ineffective. One of the most effective ways to control the lint-like accumulations is to wash them off with a forceful spray of water.

Remove Pine Cone Galls

The swollen growths on the tips of spruce branches are caused by pests called spruce gall adelgids. These growths turn brown and resemble tiny pine cones. The galls don't damage the tree but they are unsightly. If you are bothered by them, don a pair of leather gloves and hand pick them off the tips of the branches, disposing of them in the trash.

Clean Tree Wounds

If you have fast-growing trees in your yard, including cottonwoods, elms, and maples, they may begin to "bleed" from cracks on the trunk or wounds on the branches. This is often associated with a bacterial infection called "wetwood," that causes the sap to ferment and produce an unpleasant odor. This will attract a variety of insects, such as flies, sap beetles, and earwigs. The insects are not damaging to the tree so don't be talked into spraying them with poisons. Instead, just clean the oozing areas with rubbing alcohol to help dry out the areas and discourage insect activity.

Donate Today

The Garden in Every School Initiative

Special Report - Garden to Table

— ADVERTISEMENTS —