Anyone know what is happening to my pawpaw? Limb tips are dying for no apparent reason, very similar to fireblight. Mango pawpaw has a lot of issues, Wabash none and Susquehanna has one limb hit.
Mango
Susquehanna
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we had a heatwave in june in seattle WA most my trees had that i figure it was sunburnt. i just trimmed it off to were green and it has made new growth since then.
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Any caterpillar frass around dead tips?
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I’m seeing the same thing here in eastern AL - especially on mango. all of the leaves on a twig will wilt and die over the course of a week or two. I inspected those twigs very closely and there appear to be very tiny beetles probably some sort of ambrosia beetle. Never seen it before this year. They seem to only be boring into the current year’s growth - at least as far as I can tell. The wood inside the infected twigs in blueish-green.
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I don’t think it is heat related, these trees have seen some brutal temps over the years and not been effected. This year was fairly mild with good rain, it also just happened when temps are cooling, mid 80s.
I don’t see and frass like I have seen in the past on the main trunk in the spring. It does act like a beetle and like Barry it is isolated to this years growth, at least for now.
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I saw a tiny bit of frass on one leaf that was just below one of the bore-holes on a twig, but no frass otherwise - definitely no classic frass tube sticking out. We’ve had a ton of rain to wash that off if there was much to begin with. When I find a hole there are one or more beetles in there hanging out. They are extremely tiny, maybe less than a mm long. Exact same situation for me - mango hit hard but only one branch affected on susquehanna. No problems on shenandoah that I can find. I pruned off at least a dozen twigs and small branches back to clean wood on mango. Yeah kind of reminded me of fireblight pruning but hopefully this is more successful than my fireblight pruning efforts have been.
I am basically at ground zero of the ambrosia beetle and have dealt with them for years, it is odd that we are both having this same problem for the first time so far away from each other.
Ive seen them before in very early spring here on apple tree trunks that I cut back hard because of fireblight the previous fall, but have not see them on pawpaw here. I figured they went for those apple trees because they were stressed from heavy pruning, but these pawpaws seem super healthy. Let me know if you find any bore holes. I was surprised how small those holes are. It is odd that we are having the same trouble, if it turns out to have the same cause (which would not surprise me at all).
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I’ve had very early spring ambrosia beetles bore into the trunks, and kill, completely healthy 2, 3, and 4 year old pawpaws. This must be a different species based on the time of year and where on the tree they are boring. Sure hope I don’t have to deal with them.
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I have a friend with pawpaws in central IN. They had a hell of a time with ambrosia bettles eating and nearly killing their saplings last year and most of that year’s growth.
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Is this not what you’re dealing with?
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Not sure what is going on there ?
At first I thought asimina web worm, but the leafs are not wrapped up like they do. They kind of wrap the leafs into a tent with webbing . Does not appear to be , but could check to see if there are caterpillars inside those folded leaves ?
I would think ambrosia Beatles would effect the whole tree more so than individual shoots .but should check for small holes in bark.
Another possibility is Pawpaw peduncle borer. They enter through the flower base and tunnel down the pith in the twig. Could possibly cause this type of flagging on flowering size shoots.
So split some of those twigs in half to see if the pith is hollowed out
With a worm in there.?
Is the bark intact ? Cut some of those dead twigs off and dissect them.
I really don’t know what is causing this , but these are things I would look for .
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I went out yesterday and looked closer and it is some sort of insect boring into the limb. All the dead limbs had an area about a half inch long of dead almost rotten wood about a foot from the tip. One of the newer dead limbs still had the little tunnels visible but I never saw any live insects in any of the limbs.
Photos ?
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I will see if I can get out there later if it is not raining and take some pics. It is not the same ambrosia beetles that hit me in the spring, these are smaller in size.
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Sorry 
I’ve never seen anything like that before. Ambrosia beetles definitely will attack pawpaws.
Similar to periodic cicadas, other related insects will make slits in the bark and insert eggs. I know cicadas are aggressive enough with this that entire branches can be killed back, but not sure if others are as destructive.
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I could not get any good pictures, this is the best I could do.
Hole under sap
Cut showing small bore hole
They are hitting smaller limbs than the ambrosia beetles typically do in the spring. The limb in the pictures are about pencil sized whereas ambrosia beetles usually hit the trunk and larger limbs.
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That sounds identical to my problem. The beetles are so small I cant really see any features so can’t ID without a scope or magnifying glass. That and I know nothing about beetle ID haha.
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I wonder if Kentucky State, the paw paw breeding university that has released several cultivars, would have any interest in this issue? This seems like an insect pest that might be a new threat to paw paws. However I really haven’t seen them mention ambrosia beetles as threats either, which they clearly are.
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