Sugar Cane Beetle
Adult Sugar Cane Beetle
Sugarcane Beetle Euetheola humilis,
a New Pest in North Carolina Turfgrass
Amy Lockwood and Rick Brandenburg*
The sugarcane beetle, also known as the rough-headed corn stalk-beetle and in some publications referred to as Euetheola rugiceps, is a relatively new pest of turfgrass in North Carolina. It was first named and described in 1856 but was not considered a pest until 1880 when it was observed in sugarcane fields. It was first recorded as a pest of corn in 1914 in Virginia. Since then it has been a sporadic pest of the Southern States in corn, sweet potatoes, rice, and sugarcane. In North Carolina the sugarcane beetle was first noted in turfgrass about 10 years ago. Since that time it has been an emerging pest, with many reports occurring in 2009.
The sugarcane beetle belongs to the family Scarabaeidae. The beetle is dull black, about ½ inch long, and has small punctures along the abdomen which make up vertical stripes. The forelegs are designed for digging and have four projections per leg. Larvae of this beetle are C-shaped grubs. Third instar larvae (fully developed) are creamy white, may reach 1 ¼ inches long and have a red head capsule.
The sugarcane beetle has four stages: egg, larva, pupa, and adult. The beetle overwinters as an adult and emerges in early April. A lot of adult activity may be witnessed from April until early June. The adults mate during this time frame and the females lay eggs in the soil. It is unclear where exactly the female lays her eggs, though it has been reported that she looks for moist areas. After mating the adult generation dies off and activity decreases. The egg hatches into a white grub. Grubs have been found up to a foot under ground, but again their exact diet and location is yet unknown. About 75 days after hatching the larva pupates. It takes approximately 17 days for an adult to emerge from the pupa. Another surge of adult activity begins in August. The adults feed through October and then overwinter until March.
These beetles are often found on warm season turfgrasses, primarily bermudagrass, but have also been found on zyosiagrass. Adults may be found dead or crawling along the grass surface during the day or night, though activity is primarily during the early nighttime hours. Adults can also be found just under the turf, and are suspected to feed on the roots and crowns of turfgrass. Adult beetles are attracted to lights at night, and this method has been utilized to sample and monitor for this beetle. The larvae are most likely found in bermudagrass and other warm season grasses as well. It is unknown what they feed on but the organic matter in the thatch and soil is probably the main component of their diet.
Damage to turfgrass is presumed to be caused solely by the adults. Damage to the turf includes some tunneling, as well as brown and dying turf due to root and crown damage. Birds may prey on these beetles during the day and cause damage to turfgrass.
Effective management of any insect pest requires a sound knowledge of pest biology. Unfortunately we do not have a good understanding of the sugarcane beetle life cycle and biology at this time. However, we do know that adults are active during April and May and again in August through October. The use of synthetic pyrethroids such as Talstar, Menace, etc (bifenthrin), Scimitar or Battle (lambda-cyhalothrin), Deltagard (deltamethrin), Tempo (cyflutrhin) and others do kill the adults and reduce their abundance. Application late in the day is probably most effective given their night time feeding habits.
*Amy Lockwood is pursuing a Masters degree and her research focuses on the development of a better understanding of sugarcane beetle biology and ecology.
Dr. Rick Brandenburg, Wm. Neal Reynolds Professor, is co-director of the Center for Turfgrass Environmental Research and Education.