. Diseases of economic plants. Plant diseases. Small Fruits 103 leaves develop unequally, often with inrolled edges. Upon the lower surface very small spots about 1 mm. in diameter are produced, from which the diseased tissue often falls. In the older diseased spots the spore- bearing acervuli are just visible to the naked eye. Occasionally, an incipient attack may escape observa- tion during the first and second years, and even well into the third year. Then, with prospect of a good yield, the berries shrivel on the stems and later many plants die. More often the disease remains moderately in
. Diseases of economic plants. Plant diseases. Small Fruits 103 leaves develop unequally, often with inrolled edges. Upon the lower surface very small spots about 1 mm. in diameter are produced, from which the diseased tissue often falls. In the older diseased spots the spore- bearing acervuli are just visible to the naked eye. Occasionally, an incipient attack may escape observa- tion during the first and second years, and even well into the third year. Then, with prospect of a good yield, the berries shrivel on the stems and later many plants die. More often the disease remains moderately injurious from year to year, weakening the plants and diminishing the yield. In localities subject to this disease, it is best to rotate crops so as to avoid keeping raspberries or blackberries more than three years on the same soil, and to set out only healthy plants. When the disease appears, cut out and burn diseased parts immedi- ately after picking. Spray- ing with lime-sulfur is effective. Use three applications, (1) before the leaves appear, 1-20, (2) when the shoots are six inches high, 1-50, (3) just before Fig. 51. — Anthracnose on black raspberry, showing typical fis- sures. After 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
