Crepe myrtle aphid Sarucallis (Tinocallis) kahawaluokalani is an important pest of crepe myrtles throughout their range. Aphids use their piercing sucking mouthparts to extract sap from the tender, new growth of plants. Aphid feeding creates distorted/chlorotic leaves, and copious amounts of honeydew in which sooty mold grows on. Honeydew and sooty mold can coat; leaves, stems, and anything else growing underneath affected plants.
Treatment Strategy
Early detection is the key in reducing infestations of aphid. Examine areas near the buds and on the undersides of the new leaves for aphids. When natural enemies, like the lady beetle, are not sufficient in keeping the population in check, insecticides are very effective for controlling aphids. Contact insecticides can be used on exposed aphids. Soil applied systemic insecticides are also very effective and can be applied once in the fall or spring to deliver control throughout the growing season.
Other Treatment Practices
- Proper watering and the avoidance of heavy nitrogen fertilizer, which promotes succulent plant growth, can help reduce aphid damage.
Soil Drench/Injection, Systematic Bark Spray, or Foliar Spray Using Transtect 70WSP
Soil Drench/Injection or Foliar Spray Using Xytect 2F
Soil Drench/Injection or Foliar Spray Using Xytect 75WSP
Soil Injection Using Lepitect
Foliar Spray Using Up-Star Gold
Foliar Spray Using Tengard
Expected Results
Aphids are an easily controlled pest with Transtect and Xytect.
Signs of Damage
- Aphid feeding causes curled discolored leaves
- Feeding aphids excrete honeydew making the plant sticky
- A black fungus called sooty mold may be growing on the honeydew
- Aphids are slow moving, oval to pear-shaped insects ranging in size from 1/16 to 1/8 inch long
- Pipe-like protrusions extending off the back of the insect are visible with a hand lens
- Some aphids have transparent wings
- Monophagous, only found on crepe myrtle
Photo: Patrick Anderson, Rainbow Ecoscience
Photo: Patrick Anderson, Rainbow Ecoscience
Trees At Risk
- Crepe Myrtle
Biology
- Overwinter as eggs on hosts bark.
- In spring the eggs hatch and aphids migrate into summer hosts.
- Give birth to living young during growing season.
- In late summer eggs are laid.
- Several generations per year.
References
North Carolina State University:
https://content.ces.ncsu.edu/crapemyrtle-aphid-2
Texas A & M University
https://texasinsects.tamu.edu/crapemyrtle-aphid/
University of Florida
http://entnemdept.ufl.edu/creatures/orn/trees/crapemyrtle_aphid.htm
Always refer to product label for rates and approved uses. Some images courtesy of forestryimages.org or Wikimedia Commons. Use of the images does not imply endorsement of treatments.
