Last week aphids were spotted on johnsongrass in Orangeburg County and Monday they were confirmed by Clemson Entomologist Francis Reay-Jones to be sugarcane aphids. This is the first report of sugarcane aphids for the 2015 season.
This is a new pest that first showed up in South Carolina in October of 2014. Sugarcane ahpids, as it’s name suggests, traditionally have fed on sugarcane, but in 2013 it switched to sorghum. Populations can build up rapidly and can produce large amounts of honeydew that has been reported to gum up combines during harvest. Direct feeding damage can also occur reportedly causing yield reductions of 20-50% and complete losses in some instances. The photos below show an infestation on a grain sorghum leaf.
The only known instance of sugarcane aphids on sorghum in SC so far this season is in Calhoun County, but we should expect them to spread rapidly. Sorghum fields should be scouted regularly to monitor presence and population sizes.
Control options are limited. Transform has recieved a Section 18 label and Sivanto has recieved a Section 2(ee) and may be used on sorghum in SC this year. You can look at those labels here: Transform, Sivanto. These seem to be our best control options for now, though more research is being done throughout the Southeast.
For more information on sugarcane aphids, look at this fact sheet by Francis Reay-Jones and Jeremy Greene: sugarcane_aphid_pest_alert
Please report any suspected sugarcane aphids to your local Clemson Extension Agent.