. Circular. Insect pests; Insect pests. 12 THE RED SPIDER OX COTTON. locality. In all, 99 fields Avere examined as carefully as possible. The following table presents the results: Table III.—Rcsutts of (in investigation to determine the degree of infesfatif,), of cotton hij the red siyider at Lecsville, 8. C, 1912. Degree of iiifestatiun. Numl)er of fields ex- amined. Per cent of tola1 fields ex- amined. Very acute Verv considerable Sli?ht IS 20 2C Total 99 Total numl)er of fields visited Total number of fields infesled Average percentage of infestation for the commu
. Circular. Insect pests; Insect pests. 12 THE RED SPIDER OX COTTON. locality. In all, 99 fields Avere examined as carefully as possible. The following table presents the results: Table III.—Rcsutts of (in investigation to determine the degree of infesfatif,), of cotton hij the red siyider at Lecsville, 8. C, 1912. Degree of iiifestatiun. Numl)er of fields ex- amined. Per cent of tola1 fields ex- amined. Very acute Verv considerable Sli?ht IS 20 2C Total 99 Total numl)er of fields visited Total number of fields infesled Average percentage of infestation for the communit v 99 73 KiG. 7.—Cotton plant in an early stage of infestation by the red spider. Many leaves are discolored and some of the lower ones have dropped. (Original.) Fig. 8.—Cotton plant in well ad- vanced stage of infestation by the red spider. Nearly all leaves, squares, and bolls have been shed. (Original.) This occurrence was one of the severest and most general that has at any time come to the writer's attention. Perhaps the most severe case in this locality (and one of the worst yet seen) was one which had its origin in a large clump of badly infested pokeweed stalks at the edge of town (fig. 9). The pest spread fanlike until it reached in one direction a point GOO feet from the pokeweed. The final affected area, semicircular in shape, comprised 13 acres, and within its confines the occurrence was general. While such a case as this was unusual. 1-acre or 5-acre spots, with 25 to 100 per cent dam- age, are frequently to be 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 United States. Bureau of Entomology. Washington, D. C. : The Bureau
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsectp, bookyear1904
