Agrilus fuscipennis (persimmon agrilus) and Sannina uroceriformis (persimmon borer)
It doesn't take a rocket scientist (or an arborist) to see that the young persimmon tree at left probably has been invaded by borers. Two holes are clearly marked by the blackened gum around them. I think these are entry holes, but I suppose they also could be holes left by a woodpecker going after the borers.After seeing the holes in this tree's trunk, I did a little reading about tree borers and learned that two types attack persimmons: Agrilus fuscipennis or persimmon agrilus, and Sannina uroceriformis or persimmon borer
These holes are located at about 4 or 5 feet above ground level. That makes me think that persimmon agrilus is at work.
Persimmon agrilus
The persimmon agrilus is active in the lower trunk of the persimmon tree as well as the taproot. Forestpests.org offers this:
Dissections [of persimmons infected with agrilus] reveal that galleries [long holes made by the borers] are most prevalent around the root collar and commonly occur 1.2 m up into trunks and 0.5 , down into roots. However, a few galleries have been found in trunks to 2 m and in roots to 1 m.
The adult persimmon agrilus is a beetle, and it apparently lays its eggs on the trunks of persimmon trees near the ground. Damage to persimmon trees by the agrilus larvae usually does not endanger the tree's life, but it does decrease the value of its wood as lumber.
Sannina uroceriformis
The adult persimmon borer moth usually lays its eggs on the lowest portion of the persimmon trunk, rarely over 60 cm from the ground and usually much closer to ground level. She may lay eggs on the ground around the persimmon as well.
The egg-laying sites are near the ground because the freshly hatched persimmon borer larvae need to find their way to the persimmon's root system. They will spend the next year or two eating their way through the roots and creating tunnels as they go --hence their name, "borer".
The persimmon's roots can become so weak from the activity of persimmon borers that the tree falls over.
Tree borers
Don't dismiss persimmon trees just because they sometimes get borers. Many trees are attacked by borers.
If you think your persimmon or any other tree has borers, your county extension agent or university extension service is one of the best sources of specific information, available without charge.
Read more:
More about persimmon trees
More about persimmon agrilus
More about persimmon borer
Damage to persimmon roots from persimmon borer
Tree borers of the world
"The power to recognize trees at a glance without examining their leaves or flowers or fruit as they are seen, for example, from the car-window during a railroad journey, can only be acquired by studying them as they grow under all possible conditions over wide areas of territory. Such an attainment may not have much practical value, but once acquired it gives to the possessor a good deal of pleasure which is denied to less fortunate travelers."
2 comments -- please add yours:
Facinating reading.
I hope the Persimmon Tree survives as I am sure the wildlife will miss it.
You have such an informative blog... great job ;0)
Thanks for visiting, Carolyn. It sounds like most persimmon trees can survive the agrilus borer, though it spoils the lumber. Since the holes are so far above ground level, I suspect they're related to that borer rather than the persimmon borer that focuses mainly on the root system. By the way, I haven't seen a single persimmon with fruit yet this fall. I think the late freeze may have killed their blossoms.
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