[Illustration:  Apple tree windbreak at Devil’s Lake Nursery.  Hibernal in the foreground.  Patten’s Greening in the distance.]

There is another phase of protection that has been emphasized this year very much, and that is, protection against summer frosts and late spring frosts.  A gentleman living at McIntosh, near Crookston, in this state, told me that corn matured up there wherever it was protected from the north wind.  At the Devils Lake Nursery we had a 400-bushel per acre potato crop protected only by the blocks of nursery stock, whereas the yield in the vicinity was from nothing to fifty bushels per acre—­and I believe if Mr. Andrews will inquire into the location of the good apple crops about Faribault he will probably find they were saved by similar shelter protection, or the natural lay of the land.

Mr. Kellogg:  What is your best windbreak?

Mr. Maher:  The evergreen is the best windbreak for the reason that it gives more shelter, retains its leaves in the winter and fewer rows of trees will make a good shelter-belt.  The variety—­that is, west of the timber line in Minnesota—­I should say the best would be the Ponderosa pine, or bull pine, after that the jack pine may be, or else the Colorado blue spruce and the Black Hills spruce.

Mr. Kellogg:  Colorado spruce is too expensive to set out as a windbreak.

Mr. Maher:  Well, the green varieties.  I don’t see why they should be any more costly than the others.  Of course, they are held at a higher price, but they make a good windbreak because they are easily grown and are perfectly hardy to stand the dry atmosphere and the hot winds.

[Illustration:  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.