. Diseases of economic plants. Plant diseases. 378 Diseases of Economic Plants be undercut so that the fiUing will be held firmly in place, but, lest they dry out, should not be less than three- quarters of an inch thick, better an inch and a half. If there is but little undercutting, nails may be driven into the interior to hold the filling. The final cutting around the cambium should be made with a sharp knife and imme- diately followed by a coating of shellac covering the edges of the cambium, bark, and sapwood. In cavities more than two feet long, it may be necessary to reinforce the remai
. Diseases of economic plants. Plant diseases. 378 Diseases of Economic Plants be undercut so that the fiUing will be held firmly in place, but, lest they dry out, should not be less than three- quarters of an inch thick, better an inch and a half. If there is but little undercutting, nails may be driven into the interior to hold the filling. The final cutting around the cambium should be made with a sharp knife and imme- diately followed by a coating of shellac covering the edges of the cambium, bark, and sapwood. In cavities more than two feet long, it may be necessary to reinforce the remaining wood by bolts placed every 18 to 24 inches at appropriate angles. After excision is completed, the entire inner surface. Fig. 199. — Least objectionable method of an- choring guy wires to trees. After Stone. should be disinfected with creosote or carbolineum, and over this a heavy coating of tar or hot asphalt applied. The cavity may then be filled, using Portland cement and sand (1 to 3) well tamped in, the cement being put in to form blocks about 12 inches high and separated by tarred roofing paper. The face of the cement should be trimmed back to the level of the cambium. Instead of filling the cavity with cement, a mixture of dry sawdust and asphaltum, 3 or 4 parts to 1, may be used, with the advantage of greater elasticity to meet the winds. Or the cavity may be left un- filled and simply covered with a concrete layer with ap- parently equal advantages and much saving of cement. Metal coverings of tin or zinc are sometimes used, but in general are not so desirable. Shallow cavities are merely. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Stevens, Frank Lincoln, 1871-1934; Hall, John Galentine, 1870-. New York, Macmillan
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Keywords: ., bookauthorstevensf, bookcentury1900, bookdecade1920, bookyear1921
