Friday, August 5, 2016

Sugarcane aphid update and conditions for using Transform insecticide

As of this writing on Friday, August 5th, sugarcane aphids have been found over much of the Texas High Plains. Tommy Doederlein, Extension IPM Agent in Dawson and Lynn counties, raised the alarm on Monday. Today we know that fields in Floyd, Crosby, Lubbock, Hale and Hockley counties have required insecticide applications. In the northern Panhandle the aphid has been found as far north as Perryton and as far west as Bushland. We are seeing abundant winged adults, so it goes without saying that sugarcane aphids could be anywhere on the High Plains.

Scouting procedures and treatment thresholds are presented in our 2016 sugarcane aphid publication. There are only two good insecticides for sugarcane aphid control; Sivanto and Transform. By "good" I mean high efficacy with little effect on beneficial insects. Sivanto has a full label and Transform can be used through its Section 18 label. This puts some additional restrictions on Transform use, although they are not onerous. Dr. Ed Bynum summarized the conditions of the Section 18 label in his newsletter today, and here is what he said.

"The Section 18 Emergency Exemption label for Transform has some specific information regarding application use and application restrictions. A COPY OF THE LABEL MUST BE IN HAND WHEN APPLICATIONS ARE MADE.

Here are some of the specifics from the Texas Section 18 Label. However, be sure to read the label before applying.
 • Rate range: 0.75 to 1.5 oz. per acre.
 • Application by ground or air (no chemigation).
 • Wind speed not to exceed 10 mph.
 • Droplet Size: Use only medium to coarse spray nozzles (i.e., with median droplet size if 341 μm or greater) for ground and non-ULV aerial application according to ASABE (S 572.1) definition for standard nozzles. In conditions of low humidity and high temperatures, applicators should use a coarser droplet size except where indicated for specific crops.
 • Boom height for ground application: Not to exceed 4 feet.
 • Carrier volume for ground application: A minimum of 5 to 10 gallons per acre - to be increased with increasing crop size and/or pest density.
 • Carrier volume for aerial application: A minimum of 3 gallons per acre, but a minimum of 5 gallons per acre is recommended.
 • Preharvest Interval: Do not apply within 14 days of grain or straw harvest or within 7 days of grazing, or forage, fodder, or hay harvest.
 • A restricted entry interval (REI) of 24 hours must be observed.
 • Do not make more than two applications per acre per year.
 • Minimum Treatment Interval: Do not make applications less than 14 days apart.
 • Do not apply more than a total of 3.0 oz of Transform WG (0.09 lb ai of sulfoxaflor) per acre per year.
 • Do not apply product ≤ 3 days pre-bloom until after seed set."


The final bullet point about restricting Transform use from three days before bloom until seed set is there to protect honeybees. Extension IPM personnel were asked to make note of honeybees in blooming sorghum this year, so I have been paying close attention. Well, I am highly allergic to bee venom and I always pay close attention because I'm not ready for mortality quite yet. My observations on the AgriLife Research and Extension Center at Lubbock have been that it is very common for large numbers of honeybees to visit sorghum. This usually occurs early in the morning prior to 10:00 am. After that time I seldom see honeybees in blooming sorghum fields. When I get more time I may post video of honeybees in sorghum.