Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: THURSDAY, July 5, 1990                   TAG: 9007030299
SECTION: CURRENT                    PAGE: NRV-4   EDITION: NEW RIVER VALLEY 
SOURCE: Philip K. Blevins
DATELINE:                                 LENGTH: Medium

WAYS TO IMPROVE THE HEALTH OF TREES

Inadequate soil aeration, moisture or nutrients, in addition to poor climate conditions and disease, can cause problems. Always identify the cause of your problem before you try to correct it.

Trees and shrubs should be planted in soil with good drainage to a depth of at least two feet.

Low sites may be either drained with tile or elevated with fill to improve drainage.

While excess moisture is bad, the lack of it in dry periods also is bad, especially in new plantings. The lack of water kills more trees and shrubs during the first year after planting than any other cause. The root becomes established slowly, so you must supply adequate water.

Soil pH and fertility also play a major role in plant performance. Most trees and shrubs do well at a pH of 6 to 7. Exceptions to this would include andromeda, azaleas, blueberry, camelia, laurel, and rhododendron. which require a pH of 5 to 5.5.

A soil sample should be taken to determine both pH and fertilizer needs. When fertilizing shrubs follow these general guidelines:

Apply one cup of 5-10-5 to shrubs four to eight feet tall, half this to those three feet or less and twice to those more than eight feet tall.

Sprinkle this over an area starting six inches from the base and extending a foot beyond the ends of the branches. Scratch it into the grass or mulch with a rake and water in. Do this about April 10 or Nov. 10.

For trees, apply two pounds of 5-10-5 for each inch of trunk diameter measured three feet above the ground.

Spread it on an area starting two feet from the trunk and extending several feet beyond the ends of the branches. Then water it in.

Use the same dates as for the shrubs for best results.

Attractive trees and shrubs are work, but they are worth it.

Agri-Tech '90 will be held Wednesday through July 13 at Virginia Tech in Blacksburg. Things of interest to the public will begin next Thursday.

Registration will begin at 8:15 a.m. at Litton-Reaves Hall.

Thursday's activities will include tours of the Kentland Research Farm, Hickory Hill Farm, the Aquaculture Center, the Urban Pest Control Research Center, the Horticulture Gardens and the vet school.

At noon a barbecued-chicken lunch will be served (pre-registration is required, cost $5).

July 13's activities will consist of presentations on the effects of industry promotion efforts, the keynote address by the Clayton Yeutter, U.S. secretary of agriculture, and concurrent sessions on livestock research programs at Tech.