The list of diseases reported and confirmed so far this year shows the extremes in weather patterns within the state. Cedar-apple rust galls on cedars have been active for several weeks, a condition requiring moisture. Anthracnose on sycamore and bacterial blight on lilac have also been seen—both requiring moist, mild conditions. On the other hand, powdery mildew has been common on turf, and it requires cool, dry conditions. The reason we will continue to see all types of diseases is that the “textbook” conditions are usually those needed for infection. That process can occur in a few hours or a few days. Don’t let the overall dry pattern lull you into disease complacency. Other diseases confirmed at the Plant Clinic include Verticillium on magnolia, Dutch elm disease, and Cytospora canker on Douglas fir.