Handy Tips, From Trees To Bug Zappers

I bet I have the world’s largest collection of “scrap” articles. Scattered about the office, little pieces of paper containing vital gardening information have been carefully stockpiled in assorted manila envelopes and folders. In keeping with New Year’s resolution number 212, they’re either going to be categorized into booklets of organized tips or they’re headed to the big brown can next to the garage. As I wade through this collection of tidbits, I’ll pass on a few interesting gems.

As a result of damage from the November ice storm, certain tree varieties have come into question for replanting in this area - namely trees with narrow crotch angles (tight angles between branches or between branch and trunk.)

It was assumed the branches growing out of these tight angles were incapable of supporting heavy weight, especially that of thick ice coatings. If the weight was too heavy, the branches could be snapped from the tree.

However, a study in Ohio on branch strength and crotch angles of silver maples revealed that small crotch angles can provide as much strength as large crotch angles. If there was failure in the branch angle, the cause was usually that of inner tree decay or bark inclusions. (Bark inclusion is the result of two maturing side-by-side branches coming together, resulting in a tight squeeze.)

The researchers also found no differences in branch strength between silver and Norway maples, despite beliefs the silver maple is more prone to branch failure. (Source: Journal of Arboriculture, November, 1995.)

Israeli researchers report foliar sprays containing potassium nitrate can protect plants against powdery mildew. Spray every seven days with a weak solution of potassium nitrate and a surfactant. This mixture proved effective on cucumber plants, but whether potassium nitrate sprays will prove useful against mildew on other plant species remains to be seen. (Source: Crop Protection, February, 1996.)

Do we plant dogwood trees in shade or sun? Experiments conducted at the University of Tennessee have confirmed suspicions that shade can increase the severity of the fungus disease dogwood anthracnose.

Potted flowering dogwoods (cornus florida) were grown outdoors in 100 percent, 50 percent, 10 percent and 2 percent light. Some trees were exposed to moderate drought conditions by withholding irrigation and blocking natural rainfall. The most telling result was that, while only 5 percent of the trees grown in full sun were affected by the fungus, 35 percent of trees grown in shady conditions (10 percent light) were affected. Also, drought conditions did not affect disease progression with 100 percent light, but the disease spread with less light.

The researchers concluded that planting dogwoods in full sunlight and keeping them thoroughly watered should help to control dogwood anthracnose. (Source: Journal of Environmental Horticulture, December, 1995.)

A word about bug zappers - those black light traps that lure unsuspecting flying insects to their electrocution. Zappers are largely ineffective against biting flies and mosquitoes. Mosquitoes are searching for a blood meal, not light. The majority of insects caught by the zappers are harmless, non-biting insects. Many are even beneficial predators and parasites of other insects.

Figures from a University of Delaware study indicate that four million bug zappers operating for 40 nights each summer could destroy as many as 71 billion non-target insects each year, with no essential change in the numbers of mosquitoes! (Source: News Information, July 5, 1996.)

And finally, how about a recipe for growing moss. Who needs a recipe? Well, some of us do. Moss is beautiful growing in certain areas.

To establish moss, mix a handful of moss with 1/2 teaspoon of sugar and one can of beer. Blend these ingredients in a blender and spread the soupy mixture over bare ground or rocks. You can substitute buttermilk for beer. (Source: Water Colors in Rathdrum)

Well, that took care of a few slips of paper out of a stack of thousands. As I find more gems, I’ll pass them along.

, DataTimes The following fields overflowed: CREDIT = Phyllis Stephens The Spokesman-Review