Developing a White Pine Strain Resistant to Blister Rust. You can always identify the white pines because the needles are in clusters of five and there are five letters in the word w-h-i-t-e. This also applies to the sugar pine of California, which is also a white pine. Count the letters in s-u-g-a-r. Five again!
White pines have a particularly vicious enemy the disease called blister rust. Long ago scientists found that the disease spores do not go from one white pine to another; they need an alternate host, either currant or gooseberry bushes. Destroy these bushes near white pine trees and the disease is stopped. This sounds easy, but it is a very expensive and tedious job.
Well, foresters arent satisfied with that. They have found a few just a few white pine trees that are resistant to the disease. Starting with these few trees, the Forest Service and other public agencies in the United States and Canada are trying to develop a resistant strain of white pine that will still have good timber quality.
How to nail a House Together. Nails are the principal fasteners used in building a wood-frame house. How these nails are selected and used determines how solid the building will be. Its important to know the size, number, and placement of nails necessary to construct a house so it will successfully resist such forces of nature as strong winds, hurricanes, earthquakes.
The Forest Products Laboratory at Madison, Wisconsin, a unit of the Forest Service, has made exhaustive studies of nailing techniques. The results, contained in a booklet, Technique of Hose Nailing, are of value to engineers, architects, carpenters, and home-owners as a guide to the building of better houses. With the booklet one can judge the quality of the nailing in the construction of his own house.Will sandwich Houses Be Practical? The Forest Products Laboratory developed a sandwich building panel with a core of honeycomb paper. Treatment with synthetic resins makes the honeycombed paper resistant to moisture and decay. To study the suitability of such panes for house construction, a test structure was built some years ago at the Laboratory Exposure to Madisons rigorous weather for some time indicates that sandwiches will be suitable for use in buildings. Sandwich panels are now used in doors, partitions, furniture, and demountable buildings. In time they will no doubt be used in house construction.
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