From
Sandipa Gautam in the Central Valley

Hello everyone,

Please find first California red scale memo for 2024 season. CRS degree days for four counties, Kern, Tulare, Fresno, and Madera are updated on the LREC website. Please visit link for biweekly DD updates using the CIMIS station data https://lrec.ucanr.edu/Citrus_IPM/Degree_Days/.

Management choices for CRS – Mating disruption (CheckMate CRS), Biological control Aphytis melinus release; insecticides (Check UCIPM guidelines) 

How can we better manage CRS – three key points to remember

• Spray applications are most effective when populations consist of immatures and are synchronized. Spray as crawlers of the first or second generation are emerging. Expect first generation crawlers in 1-3 weeks depending on your location.  
• Monitor for CRS
• Pheromone cards for monitoring males, weekly or per flight.
• Leaf/twig sampling – sample the edge, interior or top of the tree. Determine if the scale is live or dead by rubbing your thumb.
• Use high gpa (750-1000) and drive <1.5 mph for a thorough coverage, except for Movento – apply at 250 GPA.

Attached is the first CRS memo of 2024 season with links to field trials conducted on CRS in the last decade.

Have a great season!