. Chestnut blight. Chestnut blight; Chestnut. Mar. as, 1915 Dissemination of Chestnut-Blight Fungus 497 present in the air. At the same time the growth of E. parasitica on this medium is vigorous and characteristic. As supports or stations on which to expose the plates, it was found con- venient and satisfactory to make use of the numerous large flat-topped stumps scattered throughout the coppice stand of diseased trees. To facilitate the recording of data, all of the stumps used were numbered with crayon and carefully described and located with regard to surrounding trees (fig. i). Here it ma
. Chestnut blight. Chestnut blight; Chestnut. Mar. as, 1915 Dissemination of Chestnut-Blight Fungus 497 present in the air. At the same time the growth of E. parasitica on this medium is vigorous and characteristic. As supports or stations on which to expose the plates, it was found con- venient and satisfactory to make use of the numerous large flat-topped stumps scattered throughout the coppice stand of diseased trees. To facilitate the recording of data, all of the stumps used were numbered with crayon and carefully described and located with regard to surrounding trees (fig. i). Here it may be mentioned, however, that other supports, such as the top rail of a fence or the top of a stake driven into the ground, were used in case of emergency attendant upon certain weather Fig. of chestnut coppice growth at West Chester. Pa., in and near which the experiments on wind dissemination of the chestnut-bUght fungus were earned out. The stumps, rails, and stakes used for this purpose were all of such an age or nature that they were entirely free from lesions of the chestnut blight. Under conditions of ordinary fair weather the routine followed m making the exposures was similar throughout the tests. Plates were ex- posed at the rate of one about every half hour during the day and the average length of exposure was about 5 minutes for each plate dunng the first 18 days. Then it was found advisable to lengthen the time of expo- sure, and thereafter 10 minutes, more or less, was the usual time allowed. Wind direction determined what stations were utilized each day, smce an. 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 1906-1960
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Keywords: ., bookcolle, bookcollectionbiodiversity, booksubjectchestnutblight
