Monday, June 29, 2015

Lubbock County Positive for Sugarcane Aphid

Sugarcane aphids were found in a colony on Johnsongrass on June 29th in central Lubbock County on the north fence of the Lubbock airport. Pat Porter, Extension Entomologist, found the aphids and the identification was confirmed by three other Extension Entomologists and IPM Agents. It took only ten minutes of looking to find the colony, and 30 additional minutes of looking on other Johnsongrass elsewhere did not result in additional detections. Sorghum was not sampled but soon will be. Today's earlier post confirming sugarcane aphid in Coleman, Runnels and Tom Green counties noted that the aphid could be found on sorghum, and Dr. Charles Allen said that sorghum may be the preferred host in those counties because Johnsongrass is now in decline.

Blayne Reed, Extension Agent - IPM in Hale, Swisher and Floyd counties, did not find sugarcane aphids in any of the two dozen fields he or his scouts examined in Hale and Swisher counties today. He is confident that those fields are not infested. Floyd county has not been sampled.

Sugarcane Aphids showing up in West Central Texas

Dr. Charles Allen, Extension Entomologist, San Angelo, emailed the following to our statewide Extension entomologists last Friday, June 26:

"I got a call 2 days ago from Michael Palmer, CEA Coleman County. Michael told me he had gotten an “unconfirmed report” that there were sugarcane aphids on grain sorghum in Coleman County. I went to Abilene today to attend the Texas Boll Weevil Eradication Foundation Board meeting. After the meeting, I inspected headed Johnsongrass and pre-heading grain sorghum. I found no sugarcane aphids on the mature Johnsongrass, but I found small colonies of sugarcane aphids (10 or less) mostly without winged forms present. This field was about 1 mile north of Coleman.

In Runnels County, just west of Rowena, I inspected  the south side of field of heading grain sorghum. I found winged aphids and a single newly born nymph.

In Tom Green County, just east of San Angelo, I inspected the south side of a field of heading grain sorghum. I found winged aphids and no nymphs. It was harder to find winged adults in Tom Green County than in Runnels County.

The bottom line is, sugarcane aphids are beginning to show up in West Central Texas."

Tuesday, June 23, 2015

Sorghum insecticides for all pests; which ones to choose in light of sugarcane aphid

Questions have arisen on which insecticides to use on pests other than sugarcane aphid so that the chance of having to also treat for sugarcane aphid does not increase. As more fields in Texas are treated with insecticides for various pests like stink bugs, sorghum midge, caterpillars and sugarcane aphid, we have developed some considerations for choosing insecticides for the different pests.

It is also important to treat these "other" pests at their economic thresholds and not withhold treatment out of worry about what sugarcane aphid might do.

Insecticide Selection for Sorghum at Risk to Sugarcane Aphid Infestations, 2015 .