From the Field
Degree-Day Models
Wednesday Apr 08, 2026
Have you ever wondered why different pests have different degree-day sums? Here is why:
How to Effectively Manage Codling Moth
Wednesday Apr 08, 2026
Without any intervention, codling moth numbers increase about four-fold from generation to generation. Therefore, targeting the first generation is important to reset the population size to a minimum. Control measures for subsequent generations can be adjusted to the local pest pressure indicated by trap counts.
San Jose Scale Management
Wednesday Apr 01, 2026
San Jose scale is a relatively easy pest to control, but a dangerous one to leave uncontrolled. After a few years of infestation, limbs and even entire trees can be killed if heavily attacked, and high percentages of the fruit can be infested. Large trees are most often associated with scale problems, because of the suitable habitat they provide and the difficulty of obtaining good spray coverage. However, young trees can also develop a scale problem surprisingly quickly. San Jose scale is a pest that is easily prevented, but hard to control if the populations have built up too much.
What is DAS?
The Decision Aid System (DAS) is a collaborative project between WSU Extension, the WSU Agricultural Research Center, and partners in agricultural industries. The DAS is a web-based platform designed to transfer time-sensitive information to decision makers. We run insect, disease, disorder, and horticultural models to predict on-farm conditions in real time, and link these site-specific forecasts to appropriate management and pesticide guidelines.
