Degree-Day Models

Tuesday Apr 08, 2025

Have you ever wondered why different pests have different degree-day sums? Here is why:

San Jose Scale Management

Tuesday Apr 01, 2025

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

Tuesday Apr 01, 2025

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.

Weather Data Makes DAS Run

Friday Mar 21, 2025

Around-the-clock and accurate weather data are at the core of DAS. But when they are missing, DAS cannot make model predictions. While insect and plant development models are less prone to disruption, disease models cannot run without the necessary weather input.

Western Flower Thrips

Friday Mar 21, 2025

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.