Alfalfa: Leafhoppers are not the only insect pests we can find in alfalfa during the summer. Caterpillars are another group of insect pests that can be harmful to alfalfa during the summer. Mainly, we have three species of Lepidopteran larvae in alfalfa, Beet Armyworm: Spodoptera exigua, Western Yellowstriped Armyworm: Spodoptera praefica and Alfalfa Caterpillar: Colias eurytheme. Cutting the hay can mitigate caterpillar damages. Proper identification of these species is important because they have different economic thresholds. Using the economic threshold is crucial when the crop is far from the time of harvest and you decide to apply a treatment.
The following links from: The information will provide description, damage, monitoring and management of these caterpillars.
http://www.ipm.ucdavis.edu/PMG/r1300711.html
http://www.ipm.ucdavis.edu/PMG/r1300811.html
http://www.ipm.ucdavis.edu/PMG/r1300611.html
Cotton: With windy and dry spring weather, evaporative demand is running above normal. In addition, hot and dry weather is expected later this week. Growers should closely monitor soil moisture and avoid water stress. Water stress reduces plant stature and can produce square abortion.
All the best.
________________________________________
Ayman Mostafa, PhD
Assistant Area Agent, Field Crops IPM
University of Arizona Cooperative Extension
4341 E. Broadway Rd., Phoenix, AZ 85040
Phone: 602.827.8200 ext. 313
Cell: 602.290.8061
Fax: 602.827.8292
E-mail: ayman@cals.arizona.edu
http://extension.arizona.edu/maricopa/field-crops-program