Brush Killer Products and Aphid Honeydew on Crepe Myrtles

Two separate issues here:

1. Brush Killer Herbicides

Products labeled "Brush Killer" (e.g., Ortho GroundClear, BioAdvanced Brush Killer) contain triclopyr or triclopyr + 2,4-D. They kill woody plants (brush, vines, saplings) but also kill desirable trees/shrubs if contacted. Roundup (glyphosate) is non-selective—kills all green vegetation. Use carefully:

• Cut stump treatment: Apply concentrate to fresh-cut stumps.
• Foliar spray: Only on target plants, calm days, shield nearby plants.
• Read labels—some restrict use near water or desirable roots.

2. Sticky "Rain" on Crepe Myrtles = Aphids

The dripping substance is honeydew excreted by aphids feeding on leaves. Control aphids to stop the "rain":

• Systemic insecticide (imidacloprid, dinotefuran) applied as soil drench in spring—protects all season.
• Foliar spray (insecticidal soap, neem oil, pyrethrin) for immediate knockdown. Cover leaf undersides. Repeat weekly as needed.
• Beneficials: Lady beetles, lacewings, and parasitic wasps often control aphids naturally if you avoid broad-spectrum sprays.

Don't confuse brush killer (herbicide) with aphid control (insecticide). They serve completely different purposes.