The causal fungus develops only at cool temperatures, with plenty of soil moisture, and thus does the most damage in the spring. Roots may be rotted so severely that when the fruit is developing they do not provide an adequate water supply and the plants wilt and die. Red stele can be differentiated from all the other root rots by the characteristic red-brown color of the stele or central cylinder of the root. This discoloration is readily seen by scraping off the outer part of the root. The red stele fungus will remain in the soil for at least ten years and for that time it should not be planted to strawberries without treatment.
Resistant varieties are available.
Although preplant fumigation will reduce red stele, planting in well-drained soils is more reliable. Among the compounds registered for use in Connecticut are metalaxyl and fosetyl-Al. Consult the label for dosage rates and safety precautions. Verticillium wilt, Verticillium dahliae. This disease is caused by a soilborne fungus and causes a wilt in cool temperatures.