American Elm windbreak at Devil's Lake, N. D.
Mr. Kellogg: What is the reason there are so few of them really blue?
Mr. Maher: I don't know. There is only a small percentage, probably 15 per cent., that are blue. I think the dryer atmosphere produces more blue than the more humid atmosphere. We have more blues in North Dakota than you will find even here. I believe it is the dry atmosphere and the intense sunlight that causes the blue, because the red cedar in North Dakota, the native red cedar, is really a silver cedar and has a blue sheen, or rather, a silver sheen.
A Member: How large do the trees have to be to be of benefit?
Mr. Maher: I have a friend out of Devils Lake who had 160 acres of flax destroyed by a spring wind that hits the earth at such an angle. It picked up the earth and cut the flax off, by reason of the clay hitting the little plant, except about a hundred foot strip along the west side, and that was protected by a growth of grass and weeds not to exceed a foot in height. So it depends on the kind of wind a great deal and the angle at which the wind strikes the grounds.
Now, the distance that a windbreak will protect a field has been studied out and measured and demonstrated by a great number of men. Mr. McGee, at Indian Head, gave a great deal of thought and study to the windbreak proposition and measured the distances that the shelter-belt would shelter the crops, and he came to the conclusion that for every foot in height there would be an absolute protection for a rod in distance, and outside of that actual protection there would be a long distance that would be partially protected. The same study was made by a gentleman in Iowa—I can't call his name just now—and he came to practically the same conclusion as to the distance that the protection reached in proportion to the height of shelter-belt.
Mountain Ash windbreak at Devil's Lake, N. D.
A Member: I want a shelter mostly for apple trees. Would it be five or six years before I receive any benefit, or seven or eight years?