. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 8 BULLETIN 1374, U. S. DEPARTMENT OF AGEICULTUEE stages being found immediately under the plants and only per cent between the rows. Table —Total larvse, -pupse, the and pupal cases found in the soil immediately under row and between the rows Date Under the row Between the rows Aug. 19—.-- 1921 60 69 18 33 9 18 28 27 6 13 55 Sept. 11 25 „ 6 Oct. 18 . 10 29 - 10 Mar. 23 1922 1 Do - - 16 Do 19 Do 4 Do - - 6 Total 281 138 Percentafffi of total RESTING-STAGE LARV^ IN THE SOIL Not only does the larva
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 8 BULLETIN 1374, U. S. DEPARTMENT OF AGEICULTUEE stages being found immediately under the plants and only per cent between the rows. Table —Total larvse, -pupse, the and pupal cases found in the soil immediately under row and between the rows Date Under the row Between the rows Aug. 19—.-- 1921 60 69 18 33 9 18 28 27 6 13 55 Sept. 11 25 „ 6 Oct. 18 . 10 29 - 10 Mar. 23 1922 1 Do - - 16 Do 19 Do 4 Do - - 6 Total 281 138 Percentafffi of total RESTING-STAGE LARV^ IN THE SOIL Not only does the larva of the pink boUworm, in the Laguna dis- trict, go to the soil- during the summer for transformation into the. Fig. 4.—Cocoons spun by the pink bollworm in the soil. Top row shows type of summer cocoons and bottom row type of winter cocoons adult, but to a certain extent it also passes the winter there in the resting stage. The summer larva, after entering the soil, spins a light oblong cocoon in which it pupates. Later, in the fall, some cocoons of a much heavier texture and more spherical in form are noticed in the soil (fig. 4). In these the larvse are found in the same characteristic curled-up position that they assume on passing the winter in double seeds. Observations have shown that when dis- turbed, unless it is unusually cold, the larva readily leaves this cocoon. In Tables 6 and 7 are given the results of all the soil examinations made in 1921 and 1922 cotton fields. The maximum number of living stages found at any time is shown in the second examination of 1921 when a total of 83 living larvse and pup^ were found in 1 square yard of soil. This sample was taken from a heavily infested field of very large cotton on loose sandy 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 Sta
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