What's eating my robinia pseudoacacia 'frisia'?

Robinia pseudoacacia 'Frisia' (golden false acacia) is prone to locust borer beetles, which are the most serious pest and can kill branches or whole trees. Aphids colonize new growth, and caterpillars of various moths defoliate branches. Its brittle wood makes borer damage especially problematic. Keeping the tree vigorous reduces borer attraction.

Adults lay eggs in bark cracks in autumn; larvae tunnel deeply into heartwood, causing sawdust-like frass, branch dieback, and structurally weak wood. No reliable chemical cure once inside; maintain tree vigor with good soil and watering; apply pyrethroid to bark in late summer to deter egg-laying adults.

Colonies on soft new shoot tips, especially on the golden foliage; honeydew drip and sooty mold below. Insecticidal soap or neem oil on affected shoots; strong water jet to dislodge colonies; natural predators generally keep populations in check.

Irregular holes or wholesale stripping of leaflets; silk webbing may be present with tent-forming species. Hand-pick egg masses and caterpillars on small trees; Bt spray for young larvae; pyrethroid for heavy infestations.