Commonly, the third, and fourth flights are difficult to distinguish from the 2 nd flight because the generations are starting to overlap and the heat units are accumulating very fast. The time between generations of scale is about 1100 Degree day units and so if the temperature were to stay that hot, the scale could complete their development in about 30 days. In the Kern County and the Foothill citrus growing regions, we expect the third crawler emergence to begin between August 9 th and 16 th , and continue to build through August 23. The insect is small, moving around and very susceptible to these insecticides. Esteem is very toxic to eggs and pupae of the vedalia beetle.
Vedalia beetle is the best natural control of the cottony cushion scale.
We need to avoid spraying Esteem during March through June in order to allow the vedalia beetle time to finish cleaning up the cottony cushion scale problems. Oil is still the recommended insecticide for the Aphytis release program. Generally it is applied during July. However, even oil has a negative impact on Aphytis because it can synchronize the scale stages and leave the Aphytis without 3 rd instar scale to lay their eggs in. Come to the workshop and learn about methods for sampling citricola, the complex of parasites that attack it, and current and future insecticides that are effective in controlling it.