Knowledgebase
Uses for Stump Grindings - Tree Selection #874937
Asked June 27, 2024, 10:49 AM EDT
We have a dead Noble Fir in our front yard that we are having taken down. There is no evidence of disease in the tree. The stump will be ground down below the surface, and I'm not sure whether the grindings that are left behind have any value for use in the yard. Here are a few questions:
* If we leave the grindings in the hole:
- will they decompose and leave a depression over time?
- If we plant a new tree in the same hole, will the grindings pose a problem for the new tree (too acidic, too much heat from decomposition, too much moisture retention...)
* Can the grindings be safely spread in flower beds, and/or mounded around existing plants?
* Can the grindings be used on the lawn as fertilizer?
* Can the grindings be used to fill low spots in the lawn under grass, or will they simply decompose and become a low spot again?
* What are the safe and beneficial uses for the grindings, if any?
As a secondary question, can you provide suggestions for a tree to replace the Noble Fir? The location is south facing, and gets a lot of sun all day, with almost no periods of shade. We would like a tree to provide shade to the front of the house. Considerations are:
* Water and sewer lines run underground below/near where the tree will be planted.
* Decomposition of root system of the previously mentioned Noble Fir.
* Something approximately 40' tall
* Preferably a tree that will allow grass to grow under/around it.
* Looking for a leaf bearing tree as opposed to a conifer.
Thank you,
Patrick Walsh
Washington County Oregon
Expert Response
These grindings can be used to fill in holes, but not much will grow there for awhile unless they are mixed with a fair amount of compost to allow grass to have some nutrition while the grindings decompose, which they eventually will. I would definitely not plant another tree in the grindings... best would be if you could pull native soil from another area to fill around a new tree hole.
I'm concerned that you want to plant a tree over or near water and sewer lines. The roots can often cause problems for these utilities and it would be better to think of smaller shrubs or at least keep the new tree small and as far away from these lines as possible. You don't say what killed the Noble fir, but it would be good to figure it out so you don't repeat or aggravate a problem.
A good place to start for a deciduous (leaf bearing) shade tree that can cope with full sun might be the Portland street tree lists. These will let you select how big an area you have and then give you a list of trees with their requirements as well as hints on planting, maintenance and some native suggestions.
https://www.portland.gov/trees/tree-planting/tree-species-and-planting-lists#toc-approved-street-tree-planting-lists
If you are interested in native trees, the following brochure lists large trees first followed by small trees and shrubs. Look for the ones that have the full sun icon and whatever you decide to plant, make sure to water it for a couple years in the summer to help it get established.
https://www.oregonmetro.gov/sites/default/files/2020/06/30/native-plants-for-Willamette-Valley-yards-booklet-high-res-20200107.pdf
Have fun choosing a new plant and I hope this answers your questions.
