Growths on Pignut Hickory

[uniballer]

I found these growths, and many more, on a pignut hickory on my property. I forgot to put something in the picture for scale so I will tell you that the leftmost growth in the picture is about 2.5 inches wide. The biggest one I noticed is about 4 inches long.

Any idea what these are? I cut one open to see if anything was inside and it looked solid (no insect pupating, for example).

 

[ATH]

that is called a gall. Galls can be caused by bugs (usually an aphid or wasp), bacteria, or most likely for your tree by a fungus.

I'm pretty sure that is Phomopsis Gall.

The stuff you see is actually plant tissue...the pest caused the plant tissue to react in a certain way - basically turning on and off certain growth switches, if you will.

This one is odd as I often will see one hickory in the woods just absolutely covered with them, but none of the surrounding trees implacted. In the long-term it will kill the tree (or perhaps, more accurate to say, it weakens the tree enough that secondary pests kill the tree). If the galls are big enough they will completely girdle a little twig. Not a big deal...until that happens to 10,000 little twigs. If the tree doesn't have too many, it is probably decades away from declining in health. even if they are on every twig, but you are not seeing twig die back, it has quite a bit of time. Unfortunately, there is no treatment.

 

[uniballer]

Thanks for your insight. I suspected a gall, but most of them that I am familiar with are caused by insects and often have larvae or pupae inside.

I was planning to take this tree down anyway because it is in my "too close to the house zone" from the
Just remove ash trees, or clear cut young dense wooded area thread.

Should I be concerned about disposing of this material in any particular way, or will it be unlikely to affect other trees if I just throw it in my slash pile?

EDIT: I see recommendations online to prune out the galls and dispose of them by landfill or burning to avoid spreading the fungus. I don't know how feasible this is going to be. Is it OK to throw the rest of the small branches in the slash pile?

 

[ATH]

As I mentioned, I see infected trees in the middle of others that are not. I wouldn't worry about sanitation in this case. I would clean tools as much as practical before cutting another hickory...that may be as simple as cutting through a bunch of ash after this tree, but before a live hickory...

 

[old CB]

ATH can run circles around me when it comes to plant pathology. What I know about trees is mostly how to cut them.

However, I have some acreage upstate from you, St. Lawrence County. Bitternut hickory is one of the three most dominant trees in my woods (sugar maple & ironwood, the others). Those hickories are often covered with those galls. I dropped one this spring with countless such galls on it, healthy as can be in all other regards. (I cut it for thinning purposes.) I would not be concerned with those galls.

 

[ATH]

...I dropped one this spring with countless such galls on it, healthy as can be in all other regards. (I cut it for thinning purposes.) I would not be concerned with those galls.

If I am thinning or marking for harvest, I certainly select gall-infested trees over healthy trees so I think what you did is a good call in that thinning. However, I wouldn't go out and say "get rid of all of the gall infested trees". Sometimes, as I'm sure you are well aware, you just have to find a reason to pick one over the other. That is enough to push me over the edge if all else is equal... But if I am choosing between a gall-infested hickory or an ironwood (is that Ostrya or a different species for you?), I'd keep the hickory every time.

 

[old CB]

is that Ostrya or a different species for you?

Ironwood is Hop Hornbeam, a great little tree that is often called a weed in those woods, it's that prevalent. I drop a lot of ironwood and let it rot, in order to favor sugar maple and others. But it's top notch firewood, lovely stuff to burn.

 

[waross]

that is called a gall. Galls can be caused by bugs (usually an aphid or wasp), bacteria, or most likely for your tree by a fungus.

I'm pretty sure that is Phomopsis Gall.

The stuff you see is actually plant tissue...the pest caused the plant tissue to react in a certain way - basically turning on and off certain growth switches, if you will.

This one is odd as I often will see one hickory in the woods just absolutely covered with them, but none of the surrounding trees implacted. In the long-term it will kill the tree (or perhaps, more accurate to say, it weakens the tree enough that secondary pests kill the tree). If the galls are big enough they will completely girdle a little twig. Not a big deal...until that happens to 10,000 little twigs. If the tree doesn't have too many, it is probably decades away from declining in health. even if they are on every twig, but you are not seeing twig die back, it has quite a bit of time. Unfortunately, there is no treatment.

Actually there is a treatment. Injection of fungicide. I have treated a couple hickories over the last two years. The growth of the galls cease and no new galls.

Sent from my SM-G892A using Tapatalk

 

[ATH]

Which fungicide? What is the retreatment schedule?

I could see it being useful in select circumstances...but normally I'd just let it go.

Thanks!

 

[ATH]

Ironwood is Hop Hornbeam, a great little tree that is often called a weed in those woods, it's that prevalent. I drop a lot of ironwood and let it rot, in order to favor sugar maple and others. But it's top notch firewood, lovely stuff to burn.

OK...same thing I learned as ironwood: Ostrya virginiana. Some people know Hornbeam (Carpinus caroliniana) as ironwood as well. In other regions, there are other species also called ironwood...

Certainly is a weed in the woods, but a nice ornamental in the right setting. I find they have really invaded old pastured woods.

 

[waross]

Which fungicide? What is the retreatment schedule?

I could see it being useful in select circumstances...but normally I'd just let it go.

Thanks!

In that case I used Mauget Fungisol injectors. I like the ease of use with Mauget on some things; however it does take longer to administer than my Arborjet.
However, it all depends on what I am treating as to what I use.