By Jennifer Dorsett
Field Editor

Sugarcane aphids have been found in small populations across several South Plains and Panhandle counties, and entomologists urge farmers to stay alert and treat infestations quickly if found at treatable levels.

The pests have been identified in Tom Green County, as well as Carson, Castro, Gray, Hale, Lamb and Lubbock counties, according to Texas A&M AgriLife Extension Service Entomologist Dr. Ed Bynum.

“To this point, they have been at non-treatable levels, but as we know, it does not take long for these populations to multiply into treatable levels,” Bynum told AgriLife Today. “We are advising producers to be diligent in their scouting and take actions before heavy infestations build up.”

These tiny insects initially infected sugarcane crops but made the jump to grain sorghum in the 2013 growing season, causing farmers to lose up to 50 percent of grain yields that year.

AgriLife Extension entomologists recommend scouting sorghum fields at least once a week for signs of aphids, including “honeydew,” a shiny, sticky substance secreted by the pest.

Aphids damage sorghum by feeding on the plant, and the honeydew they leave behind can attract a fungus called black sooty mold, causing further harm to plant health. Honeydew can also clog harvesting equipment.

When infestations reach an active threshold, treatment should begin immediately. Preventing lower infestation levels from moving to higher populations is vital in preventing severe losses to the crop.

Entomologists recommend treatment in the High Plains when:

  • 20 percent of plants have aphids in the pre-boot stage;
  • 20 percent of the plants in the boot stage have more than 50 aphids;
  • 30 percent infestation of plants in the flowering-milk stage;
  • 30 percent infested with localized areas of heavy honeydew and established aphid colonies when plants are in soft dough and dough stages.

When the black layer growth stage is reached and heavy honeydew and established aphid colonies are present, treat only for preventing harvest problems.

Sugarcane aphids have unfortunately become an annual pest for sorghum farmers, Dan Berning, DuPont Pioneer technical services manager for the western Corn Belt, said in an interview with the Texas Farm Bureau Radio Network.

“These populations tend to explode fairly quickly, especially when we have higher temperatures and drier conditions,” Berning said.

He noted selecting tolerant hybrid plants and scouting and treating with insecticides as necessary can be effective in dealing with sugarcane aphids.

Field trials have shown only two chemicals—Transform and Silvanto—provide good control of the aphid, according to Bynum.