Palmetto Weevil
Rhynchophorus cruentatus
The largest weevil in North America, a big black or red snout beetle whose grubs bore into the crown of stressed, wounded, or recently transplanted palms. By the time the crown collapses and the top folds over, the palm is usually beyond saving.
🔎 How to spot it
Adults are large, three quarters of an inch to over an inch long, and vary from solid black to mostly red with a black pattern, with a long curved snout. The legless grubs are creamy to yellowish with a hard dark-brown head and can grow very large. Early infestation is hard to spot; a late sign is the crown wilting and the top of the palm falling over, sometimes called popped neck.
🥀 Damage it causes
Females lay eggs in leaf bases and wounds, and the grubs tunnel into the soft tissue near the growing point and destroy the bud. Younger leaves decline irreversibly and the crown structure fails so the top folds over and the palm dies. The weevil targets stressed, dying, and freshly transplanted palms rather than healthy ones.
🛡️ Prevent it
Keep palms healthy and unstressed with proper watering and fertilizing, and avoid wounding the trunk and crown, since wounds and transplant stress attract egg-laying females. Take special care with newly transplanted palms, which are the most vulnerable. Choosing climate-appropriate palms reduces the cold and stress injuries that draw the weevil.
🧯 If it is already here
Remove and destroy infested palms before the adults emerge to keep the weevil from spreading. Preventive insecticide treatments, including systemic neonicotinoids, can protect high-value or newly transplanted palms. Because the damage is deep in the crown, prevention and early action are far more effective than rescue.
💡 Good to know
The complete life cycle takes about eighty days, and the weevil is native to the southeastern United States. Native cabbage and saw palms are rarely killed because the weevil prefers severely stressed trees, but introduced palms such as Canary Island date, Bismarck, royal, and coconut are at greater risk when newly planted. It is a relative of the destructive red palm weevils watched for worldwide.
🌱 Plants it attacks
4 plants in the library can be attacked by this pest
For educational and informational purposes only. Pest control advice is general guidance drawn from university cooperative extension sources; always identify a pest positively and read and follow the label on any product before use, especially around food crops, children, and pets.