. Manual of tree diseases . Trees. OAK DISEASES 253 and the larger roots. The decay extends from the surface of the ground upward in the heartwood for a distance of one to a few feet and in its final stages leaves a large hollow cavity. Symptoms. When badly rotted trees are cut, they fall after the thin shell of heartwood is cut through and the trunk carries with it the partially rotted hollow cylinder of wood from the stump. The odor of the freshly cut rotted wood is very strong and resembles anise oil. The first indication of the decay is seen in longi- tudinal section as a yellowish or whit
. Manual of tree diseases . Trees. OAK DISEASES 253 and the larger roots. The decay extends from the surface of the ground upward in the heartwood for a distance of one to a few feet and in its final stages leaves a large hollow cavity. Symptoms. When badly rotted trees are cut, they fall after the thin shell of heartwood is cut through and the trunk carries with it the partially rotted hollow cylinder of wood from the stump. The odor of the freshly cut rotted wood is very strong and resembles anise oil. The first indication of the decay is seen in longi- tudinal section as a yellowish or whitish area from four to eight. Fig. 50. — Fruiting-body of Polyporus Berkeleyi. inches long. The summer-wood in this region is delignified and the ipdividual fibers are separated by the dissolving of the cementing layer between them. As the decay progresses the dense whitish summer-wood is completely destroyed. This leaves the medullary-rays and strands of porous spring-wood intact. The interwoven rays and strings of wood are brownish at first but soon are covered with whitish mycelium. The strands slowly become more brittle and finally collapse, leaving a hollow cavity. The decayed area becomes larger and is bordered by a zone of whitish wood with the string and ray rot stage projecting into the hollow cavity. The sporophores arise from the exposed larger roots or may. 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 Rankin, W. Howard (William Howard), b. 1888. New York : The Macmillan Company
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1918
