What's eating my totem pole cactus?

Totem Pole Cactus (Lophocereus schottii 'Monstrosus') is a smooth, spineless columnar houseplant. Its lack of spines means pests have fewer hiding places, but mealybugs still congregate in the depressions and folds of its monstrose skin. Scale insects and spider mites are secondary threats. Root mealybugs can lurk undetected in the soil below the large column.

White cottony clusters in the skin folds and dimples of the monstrose surface; sticky honeydew and weakened growth Wipe affected areas with isopropyl alcohol on a soft cloth or swab; spray with neem oil or insecticidal soap; repeat every 7–10 days

Brown or cream flat shields adhered to the smooth skin; yellowing or sunken patches at feeding sites Scrape off with a soft brush dipped in rubbing alcohol; follow with neem oil spray; systemic insecticide for heavy infestations

White powder on roots; large column may slowly lean or show basal softness without obvious above-ground pest signs Inspect root zone when repotting; wash roots and repot in fresh cactus mix; drench with imidacloprid solution if confirmed