- Author: Elizabeth E Grafton-Cardwell
In Tulare County, the first flight of male red scales began the week of March 19, so we are using that as the biofix for the San Joaquin Valley. As our degree day page shows http://ucanr.org/sites/KACCitrusEntomology/Home/California_Red_Scale/Degree_Days_885/
the scales have accumulated 117-171 degree days so far, depending on location. This is well below the 30 year average of closer to 300 degree days by the middle of April. The warming trend this week should speed things up. We expect the first generation of scale crawlers to emerge at 550 degree days. Please log onto my web pages to follow the degree day accumulations as the season progresses.