From the Field
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.
Powdery Mildew of Cherry: Fungicide Resistance Management Guidelines Spring 2019
Wednesday Apr 01, 2026
Cherry growers in the Pacific Northwest have multiple fungicides at their disposal for managing powdery mildew. Products in the powdery mildew “toolbox” include members of the DMI, QoI, SDHI, quinolone synthetic compounds and multiple “contact” fungicides from other classes (e.g. sulfur and narrow range petroleum oils). A more inclusive list of fungicides is presented in the table below. The table includes fungicide class information, Fungicide Resistance Action Committee (FRAC) group number or code, and resistance risk.
Western Flower Thrips
Saturday Mar 21, 2026
Western flower thrips feeding causes bloom distortion and poor fruit set. Egg-laying punctures create "pansy spot" on some cultivars. Adults can be sampled using either beating trays or blue sticky cards.
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.
