Spittlebug Infestation on Variegated Dogwood

White Frothy Substance on Dogwood Stems? Spittlebugs

A variegated dogwood showed crinkled, holey, curling leaves for two years. White liquid substance found on stems during trimming raised disease concerns.

Diagnosis: Spittlebug (Froghopper) Nymphs

The white "liquid" is actually a protective foam produced by spittlebug nymphs feeding on stem sap. The foam hides them from predators and prevents desiccation. Adults are small, inconspicuous jumping insects. Feeding causes leaf distortion, stunting, and cosmetic damage but rarely kills established shrubs.

Control Measures

• Strong water spray to dislodge foam and expose nymphs.
• General insecticide (e.g., pyrethroid, neem oil, insecticidal soap) applied to stems and leaf undersides for nymph control.
• Monitor in spring for first foam appearance—treat early for best results.

Additional Notes

Variegated dogwoods may be more susceptible to stress. Ensure adequate water, mulch, and avoid excessive nitrogen fertilization which promotes succulent growth attractive to sap-feeders. The leaf damage described could also involve other pests; inspect for aphids, scale, or leafhoppers if spittlebug control doesn't resolve symptoms.