Persimmon Borer
Sannina uroceriformis
A native clearwing moth whose larvae bore in the lower trunk and roots of American persimmon, tunneling through the cambium and into the taproot. It matters most in fruit growing because American persimmon is widely used as the rootstock for grafted Asian persimmon, and a girdled rootstock can weaken or kill the grafted tree.
🔎 How to spot it
The adult is a bluish black, wasp-like clearwing moth with a wingspan of about one and one eighth to one and one quarter inches. The larva is a pale, legless caterpillar found tunneling in the wood at the base of the trunk and in the roots. Because the damage is below or near the soil line, the borer itself is rarely seen without digging into the affected wood.
🥀 Damage it causes
Larvae tunnel in the cambium downward and, at or near the soil line, bore into the wood toward the center of the taproot and lateral roots. This feeding scars and can girdle the lower trunk and roots, weakening the tree, slowing growth, and on grafted trees endangering the persimmon rootstock that supports the fruiting top. Attacks concentrate at the base, so decline and instability there are the warning signs.
🛡️ Prevent it
Keep trees vigorous and avoid wounding the lower trunk with mowers and trimmers, since injuries and stress attract egg-laying clearwing moths. Inspect the trunk base and root flare of persimmons for tunneling, frass, or dead bark, and remove and destroy heavily infested wood. Protecting the graft union and rootstock of grafted Asian persimmon is the main concern.
🧯 If it is already here
There is no simple cure once larvae are deep in the roots, so management centers on keeping trees healthy and removing infested ones that serve as a source. On valued trees, individual tunnels can sometimes be probed, and trunk-base treatments timed to adult flight may protect against new attacks. Because this borer is specific to persimmon, moving the planting away is not practical, making vigor and sanitation the main tools.
💡 Good to know
The persimmon borer is found across the eastern United States and attacks only persimmon, with the native American persimmon its true host. Its life cycle takes two to three years to complete, so a tree may carry larvae of different ages at once. No natural enemies of this species have been recorded, which leaves cultural care as the main defense.
🌱 Plants it attacks
3 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.