6 FARMERS’ BULLETIN 1735. 
period of about 18 hours, begins to deposit her eggs. They are 
usually clustered rather closely, rarely occupying an area greater 
in size than that of a dime. 
For about 8 to 10 days the female lays usually about six eggs 
per day, thus making a total of about 50 to 60 eggs. Feeding 
continues from time to time throughout the egg-laying period. The 
average duration of adult life in summer, in South Carolina, is 
about 12 days. This period increases as the weather becomes cooler, 
and in winter the adults often live for 150 days. 
RELATION OF WEATHER TO BREEDING. 
Climatic conditions influence the development of the red spider 
to a marked extent. The influence may be either harmful or bene- 
ficial. In the course of the year the occurrence of the pest under- 
goes many changes. During December, January, and February the 
red spider merely maintains itself, but during March conditions 
usually become a little more favorable. Through April and May 
development progresses most rapidly, and infestation reaches its 
height on miscellaneous plants by June 1. Beginning about the end 
of September, a reduction begins in the numbers of the red spider, 
and this reduction continues as the weather becomes colder, until, 
by .the end of November, the low point is again reached. Hot, dry 
conditions, such as occur during times of drought, hasten develop- 
ment, while cool, wet weather retards it. A female laying normally 
about six eggs per day will, upon the occurrence of a hot day, 
suddenly increase the number, often to 15 or 20 eggs per day, or 
upon a chilly day the number deposited may drop as suddenly to 
one egg or none. 
DISPERSION. 
When cotton and other annual plants die in the late fall the red 
spiders are forced to seek green food. Many of them manage to 
locate upon the several kinds of weeds (mentioned on page 4) which 
remain green throughout the winter. Since these wild plants occur 
abundantly in the borders of fields and on terraces and roadsides, 
the pest frequently is found on cotton the following spring, in the 
portions of fields where planters fail to clear these borders of weeds. 
The cultivated violet occurs frequently throughout the South, and 
remains green through the winter. Infested violet beds have been 
found from Virginia to Texas, and in many cases they are the sources 
of infestation to near-by cotton fields. The infestation to cotton may 
arise directly from violets, if the beds are within a few hundred 
feet of cotton (fig. 6), or from a series of migrations covering con- 
siderable distances. 
A peculiar sort of red-spider infestation arises from pokeweed, 
which occurs commonly on terraces and along field borders. Owing 
to its long growing period it rarely becomes heavily infested until 
