How much damage might we accidentally do to our ash tree?

We live in a suburb and are participating in our city's "flip your strip" program, which will pay us to remove grass from the parkstrip. We were getting rid of all of the grass anyway, and thought we might as well collect money for this part of the project if they way to give it to us

The problem is that the parkstrip (i.e. growing space between the sidewalk and the street) is sloped, with the sidewalk uphill from the street. Not only that, the soil is actually mounded up *above* the sidewalk level before sloping down--as much as 6" in some places. There's a youngish ash tree planted in the strip, I'd estimate 10-15 years old.

We killed the grass by burying it deeply in leaves and wood chips over the winter, and have just been digging out the last stragglers around the base of the tree and the edges of the strip. I'd hoped to dig a bit of a basin around the tree, and in any case the program guidelines say we should dig down 3-4" below sidewalk level to accommodate the mulch we'll be putting in.

But even digging down a couple of inches--not even to sidewalk level--exposes and breaks tree roots the thickness of my fingers.

How important are these roots? Can the tree withstand some damage to them, or should we give up the idea of digging at all?

You might check to see what the emerald ash borer predictions are in your area.  If they are bad, it might be best to go ahead and replace the tree with a different species.

I find that a very strange proposal. Why are they paying you to remove grass?

What are you planning to have there instead?

Jae, thank you for sharing about "Flip your Strip" as it looks like several cities are adopting the idea.

As for your tree roots, I don't like to disturb tree roots that are close to the trunk.  Maybe you could hide the roots under wood chips rather than remove them.

I hope you will share a little more about what your plans are.

replace it with water-efficient landscaping using drip irrigation

https://jvwcd.org/file/21deb524-b059-49ab-afd5-22e7bc42bb88/Flip-Your-Strip-Program.pdf

And this one:

No, this program requires plants and drip irrigation to be installed. This rule is in place to follow local city ordinances.

https://utahwatersavers.com/Program/2/flip-your-strip

Has that strip been irrigated in the past?  That might explain if the reason behind lots of surface roots.  Is the mulch going to be wood chips?  I hope so...  Can you just leave the root area alone and cover with chips or would it be too high?  Digging out 3" around a tree in an irrigated yard might damage it.  

Could you put in a dainty retaining wall just above the curb to allow for adding mulch without digging?

I'm sorry Jae.  Referring to the WesternGarden book on the shelf - Perhaps the root-store was not damaged, and only the root-tips-feed area is damaged.  Not a great situation, but the root-store might keep the tree thriving through the summer and autumn.  Anyway, if you have the WesternGarden book, I'm looking at the "basic planting and care" section, "how plants grow" subsection.

And along the lines of this project, I live in a city where the city "owns" the trees on the verge, but I am responsible for the sidewalk being smooth and flat.  I cannot prune, or touch the tree. Should the city's trees damage the pavement, I have the honor of paying at least 50% of repairs.  After some 10 years of repeated damage, I have the honor of paying for the removal of the city tree!   And now the kicker - the contractor the city use to "repair" the pavement just cut the root-tips area - just whack away at them, literally - no concern at all for the health of the tree.  Ugh.

Gray Henon wrote:You might check to see what the emerald ash borer predictions are in your area.  If they are bad, it might be best to go ahead and replace the tree with a different species.

Thanks Gray! There are a lot of ash trees in the neighborhood and they all look healthy, and I'm loathe to get rid of a well-established tree even though I might later regret not having taken action. Also, since the tree is technically the property of the city, I'm not sure that would be straightforward to do.

Michael Cox wrote:I find that a very strange proposal. Why are they paying you to remove grass?

What are you planning to have there instead?

They're paying us to remove grass to save water. Utah, where I live, is the second driest state, and has the second highest per capita water use due to irrigating completely unrealistic landscaping and crops. Parkstrip grass is the worst because sprinklers always overspray and end up watering the sidewalks and streets, so they've got rebates to take out the grass and put in either low-water ground cover or low-water ornamental plants that will result in at least 50% coverage of the strip at maturity, with 3-4" mulch and drip irrigation.

They should be incentivising  curb cuts and rain gardens, but that would be hoping for too much. At least they're not promoting just rocks, which kill the soil and raise the temperature.

Anne Miller wrote:Jae, thank you for sharing about "Flip your Strip" as it looks like several cities are adopting the idea.

As for your tree roots, I don't like to disturb tree roots that are close to the trunk.  Maybe you could hide the roots under wood chips rather than remove them.

I hope you will share a little more about what your plans are.

replace it with water-efficient landscaping using drip irrigation

https://jvwcd.org/file/21deb524-b059-49ab-afd5-22e7bc42bb88/Flip-Your-Strip-Program.pdf

And this one:

No, this program requires plants and drip irrigation to be installed. This rule is in place to follow local city ordinances.

https://utahwatersavers.com/Program/2/flip-your-strip

Hi Anne! That Utah program is the one we're doing. We live in Salt Lake City, and it's all-hands-on-deck right now to save the Great Salt Lake... at least in our area.

Thanks for your thoughts on the tree roots. They are so abundant and shallow, I called the Localscapes people who are administering the program and got their permission not to dig down. That feels like a good decision, but it does mean we'll have to stay on top of sweeping the mulch that slides onto the sidewalk back up onto the parkstrip. I wish we could have started from scratch and created a rain garden instead, but that's the downside of buying a home in a historic neighborhood: nothing is from scratch.

I do love the tree.

Mike Haasl wrote:Has that strip been irrigated in the past?  That might explain if the reason behind lots of surface roots.  Is the mulch going to be wood chips?  I hope so...  Can you just leave the root area alone and cover with chips or would it be too high?  Digging out 3" around a tree in an irrigated yard might damage it.  

Could you put in a dainty retaining wall just above the curb to allow for adding mulch without digging?

Hi Mike! Yes, the strip has been irrigated with sprinklers... shallowly. And in fact since we killed the grass with 10" of wood chips over the winter, and haven't watered yet this year, the tree is looking very thirsty.

The mulch on that strip will definitely be woodchips, as deep as we can manage. We got the plants put in over the weekend and I'm watering deeply now, and the drip irrigation guy will be here in a couple of weeks to sort that out. I thought about a dainty retaining wall, but as a former personal trainer to people in their 80s and 90s I know that a little bit of edging or retaining wall that only sticks up a few inches is the worst kind of tripping hazard. Nobody sees it. So I think we're just going to end up sweeping the sidewalk a lot.

calbo collier wrote:I'm sorry Jae.  Referring to the WesternGarden book on the shelf - Perhaps the root-store was not damaged, and only the root-tips-feed area is damaged.  Not a great situation, but the root-store might keep the tree thriving through the summer and autumn.  Anyway, if you have the WesternGarden book, I'm looking at the "basic planting and care" section, "how plants grow" subsection.

And along the lines of this project, I live in a city where the city "owns" the trees on the verge, but I am responsible for the sidewalk being smooth and flat.  I cannot prune, or touch the tree. Should the city's trees damage the pavement, I have the honor of paying at least 50% of repairs.  After some 10 years of repeated damage, I have the honor of paying for the removal of the city tree!   And now the kicker - the contractor the city use to "repair" the pavement just cut the root-tips area - just whack away at them, literally - no concern at all for the health of the tree.  Ugh.

Thanks, Calbo! I have that book but it never occurred to me to consult it. Doh!

Our situation with the parkstrip trees is very similar, though I don't know all the ins and outs. My plan is just to love it and take very good care of it.

Emerald Ash Borer (EAB) arrived in the US from China, in 2002 near Detroit. 40 States are now infested. It is nearly always fatal to ash trees. It is thought to have not yet arrived in Utah. But it will.

I would talk to the city or county gov't about EAB, and what their plans are when it kills the trees. Here in N. Ohio, they sprayed bug poison from the air, they banned transport of firewood across county lines, they tried culling infected trees. It did absolutely no go. All the ash are dead. The same is coming your way.

If you have young ash trees you might as well cut them down now when it will be much less expensive. There are many other species of trees that are not affected. Maybe plant oak or maple or honey locust. I would do it now, and later you will have shade when all your neighbors do not.

Check out Brad Lancaster on youtube.  He has done some really amazing things with street trees and water harvesting.