Occurrence of Psorophora columbiae eggs in different field types comprising a Texas riceland agroecosystem

Soil samples (3,258) were collected from soybean fields, rice fields and permanent pastures in Chambers County, TX over a 2 1/2-year period and examined for the presence of Psorophora columbiae eggs. Eggs occurred more frequently and in greater numbers in samples taken from soybean fields than in samples from either rice fields or permanent pastures during the summers of 1979 and 1981 when there was heavy rainfall in the study area. Under dry conditions, as during the summer of 1980, the frequency of egg occurrence and abundance increased in samples taken from rice fields. However, egg occurrence and abundance in soybean field samples still remained relatively high even during this particular year.