How to save dying Green Ash with dirt around base?

[acmpls]

I recently bought a house in Minneapolis that has a green ash (I think) in the front yard. I don't know how old the tree is but the trunk diameter is about 3 feet and the height is maybe 40 feet. The previous owners must have been amateur landscapers because they built a 1 foot tall circular concrete block wall about 9 feet in diameter around the tree. Then they filled in the area with dirt and planted about 10 hostas around the tree. The dirt measures 6-8 inches around the base of the tree. I think the wall was built 2 years ago and the tree looks very sick with several dead branches.

I've read several threads indicating that this is the exact wrong thing to do for a tree, but now that it's done, is there any way to save the tree? Can I remove the dirt from around the base of the tree but leave the hostas there? Or should I dig up all the hostas and remove the all the dirt from around the base of the tree? Or is it too late to do anything?

 

[Rtom45]

Removing the dirt completely would be a start. The tree may have other problems causing the symptoms you are seeing. Posting some pictures will help people on this board identify the problems.

 

[acmpls]

Here are some photos

Yesterday I started digging around the trunk and put in some plastic edging to keep the dirt away. However I realize I probably need to dig out all the dirt, not just right around the trunk. I could care less about the hostas at this point, I just want to save the tree.

Thank you for your help.

Adrian

 

[gink595]

Emerald Ash Borer??

 

[acmpls]

Emerald Ash Borer??

The emerald ash borer hasn't been found in Minnesota yet. Hopefully this isn't the first case.

 

[appalachianarbo]

Remove the dirt, stones, and hostas down to the original root flare level. Don't damage any roots. Apply 4" of mulch as far out as you can (to the dripline is ideal). You can mow the grass as low as possible beforehand. Keep the mulch off the trunk.

More photos of the whole tree canopy would be nice.

Yup.

 

[acmpls]

Photos of canopy

Thanks everyone for the advice so far. Here are some more photos I took last night. Clearly I'm not an arborist but I noticed that when a large branch has both dead and alive branches on it, the dead/dying branches seem to be on the bottom and the alive ones on top. Not sure if that's typical or not.

 

[sawyerDave]

Good pics, from my experience, which is limited to looking at pictures from the dept of agriculture, when EAB hits, it will cause 1/2 the tree to flag (go yellow), as the EAB makes galleries under the bark, kind of in a zigzag direction. In this case, I would be more worried about root damage, pull out that plastic liner around the bottom of the tree, and see if some intellectual giant did something smart like sawing a kerf into the base of the tree, to install that plastic. Do some digging, and post pictures.

 

[KsWoodsMan]

I thought with EAB the tree dies from top down.
With root problems it dies from the bottom up.

No expert here but uncovering those roots and getting that soil awy from the bark might bring it back if the trunk is still healthy enough to support a growing tree.

 

[acmpls]

Do I have to remove the dead branches?

I thought with EAB the tree dies from top down.
With root problems it dies from the bottom up.

Do I have to remove the dead branches? Not sure if you can tell from the photos but most of the dead branches are toward the bottom of the tree, so it would make sense that roots are the problem. The top branches seem mostly healthy.

 

[computeruser]

Looks like the early stages of EAB to me. The "top down" isn't universal with EAB. It can start with branch-tip death in one area, all around the canopy, or at the top. It can even start on one side and migrate to the other. The tree then starts trying to send out new shoots along branches, on the trunk, wherever. Then it just gives up and dies.


My sense from the pictures is that the tree is on the way out, one way or another.

 

[acmpls]

Well guys whatdya think?

Took about 3 hours to remove the hostas, dirt and bricks, then lay down the cypress mulch. Is there anything else I can do at this point? Water it a lot?

I'm no expert but I think EAB is unlikely considering it has never been reported in the state of Minnesota before. If it was EAB I'm sure the Dept of Agriculture would be very interested to know. Perhaps there's another type of borer at work...

 

[appalachianarbo]

Looks awesome. Good job! While you had the flare exposed, did you notice any girdling roots, decay, pathogens, etc.?

You could sacrifice some more of your lawn to the mulch. A mulch ring can never be too wide! I bet a good vertical mulching would do wonders for this tree.

Water if you don't get any rain - feel the soil under the mulch. If its too dry, add water, and vice versa.

I think the tree will do a lot better now. It'll be a wait and see though.

 

[Mr.Roehler]

If it's a root problem the tree will die from the top down. The nutrients will be insufficient for the entire tree and will start to slowly down from top to bottom. It doesn't look to be the EAB. I would say that most likely there is something with the roots or if it's the lower dead they're just being shaded out by a think canopy and should most likely be removed. A fertilization program might also be a good place to start to increase the vigor of the tree. No good pictures of the canopy but perhaps thinning but if the tree is stressed make sure it's not to excessive.

 

[acmpls]

Looks awesome. Good job! While you had the flare exposed, did you notice any girdling roots, decay, pathogens, etc.?

You could sacrifice some more of your lawn to the mulch. A mulch ring can never be too wide! I bet a good vertical mulching would do wonders for this tree.

I've extended the mulch out another couple of feet. I looked at the roots when they were exposed but I didn't really know what to look for. The large roots looked strong. Also the smaller roots had been growing up into the hosta bed above the normal lawn grade (you can see this in the photo close up of the roots). It was difficult to remove the dirt without damaging the smaller roots, although the larger ones were easy to avoid.

 

[def38]

Save the tree

I was born and raised in Edina (Drexel Ave) and recall the wonderful large trees that lined the streets there. It would be a shame if you loose your tree. Keep us posted...opcorn:


I am rooting for your tree (no pun intended).

 

[Woodie]

I'd like to know a little bit more about this root right here:

I'm not used to seeing surface roots like that on an ash tree. What would cause that? Is it possible your lawn was one of those "put two inches of topsoil on top of hardpan clay" lawns?

I have to say it doesn't look like EAB to me, given that it's dying from the bottom, and the beetle hasn't been reported in your state yet. The easiest way to tell is to examine the bark all around for D-shaped holes. They'd be the size of a woodpecker hole, but they're shaped perfectly like a capital D.

Caveat: I'm not an arborist, nor have I played one on TV, nor have I stayed in a Holiday Inn Express anytime in the last two years.

 

[Woodie]

One other thought...you have a good-looking lawn there...not a weed in sight. Do you apply a great deal of weed-killer to it? The break-down salts present in broadleef weedkillers can sometimes do a number on even fully grown trees.

 

[acmpls]

One other thought...you have a good-looking lawn there...not a weed in sight. Do you apply a great deal of weed-killer to it? The break-down salts present in broadleef weedkillers can sometimes do a number on even fully grown trees.

It's funny that you mention that because the weeds have begun to take over and I was thinking about getting some weed killer. I haven't done a thing to the lawn yet, but I can't speak for the previous owners.

My neighbor told me that there is sand below the soil...I don't know how that would affect the tree. There are lots of large trees in the area and I also have a large old elm in my yard.