What's eating my mahonia pinnacle?

Mahonia aquifolium 'Pinnacle' is susceptible to mahonia rust and aphids like other Oregon grapes. Outdoors it also faces vine weevil and occasional slug damage on young plants. Its spiny holly-like foliage generally discourages deer and rabbits, though harsh winters can drive deer to browse the lower leaves.

Orange-brown spore pustules on leaf undersides, yellow-green spots on top, early leaf drop Cut out and dispose of infected foliage; use copper-based fungicide; avoid overhead watering

Sticky residue and distorted growth on young shoots in spring and early summer Strong water jet to dislodge; neem oil or insecticidal soap spray; encourage beneficial insects

Irregular notches on leaf edges (adult); wilting from larval root feeding, especially in containers Apply entomopathogenic nematodes in late summer; use physical barriers; inspect rootball when repotting