# Stump-Grindings as Garden soil? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 29, 2019, 6:29pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728 "2019-03-29T18:29:10Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Grestarian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/grestarian/32/3227_2.png) [@Grestarian](https://boards.straightdope.com/u/Grestarian)\ **Post date:** [March 29, 2019, 6:29pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/1 "2019-03-29T18:29:10Z")
Mods: I’m asking for opinions but, if you think small gardening matters belong in Cafe Society, feel free to relocate this. Hey, gardeners, I got an odd question for you all. Last week the city removed three coco palm trees from the parkway in front of my house. It took five guys with heavy machinery about three hours to remove three trees that were each over a hundred feet tall. I was very impressed. The crew even brought in a machine that looked like a giant circular saw and ground the stump to powder. The guy running that machine assured me those trees were never coming back. Great! But can I use that powder for something else? The spots where the trees stood are kind-of high and I’d like to level them out and put sod squares (just like the surrounding grass) there to make a unified mow-able strip along the parkway. Coincidentally, my wife is talking about putting a raised planter in the back yard. Q1: After I build the planter for her, can I fill it with the grindings? Once she starts watering and nutrifying her flowers or veggies or whatever, will those old palm trees start coming back? Q2: And do we need to supplement those grindings with real dirt/fertilizer for the flowers/veggies/whatever to grow in, or will the plantings consider that ground-up stuff to be suitable as soil? –G? Mary, Mary, quite contrary, How does your garden grow? With silver bells, and cockle shells, And pretty maids all in a row. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [March 29, 2019, 6:53pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/2 "2019-03-29T18:53:35Z")
No, your stump grindings aren’t going to produce new trees. But no, you can’t just use them as soil all by themselves, any more than you can sow plants directly in other kinds of sawdust. If the trees were healthy and not contaminated with pesticides and such, you could use the grindings directly as mulch on garden beds, or on an unpaved path. If you want to get soil out of them, you should compost them with other organic materials, which would probably take a year or so to make good dirt. What I’d be inclined to do, if you’re building your backyard raised planter directly on the ground, would be to put a layer of the grindings on the bottom and then fill the planter with soil. It should help drainage in your planter to begin with, and over time it will naturally compost into dirt. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [March 29, 2019, 6:58pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/3 "2019-03-29T18:58:12Z")
Wood chips of various kinds\* make good mulch and can be used as soil amendments, but it’s typically suggested that if using them in quantity in a soil mix, make sure to add extra fertilizer to break down slowly and make up for nutrients lost in the wood decomposition process. ---
**Author:** ![Kimstu](https://avatars.discourse-cdn.com/v4/letter/k/ecd19e/32.png) [@Kimstu](https://boards.straightdope.com/u/Kimstu)\ **Post date:** [March 29, 2019, 7:14pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/4 "2019-03-29T19:14:37Z")
> [@Jackmannii](#): > > Wood chips of various kinds\* ? Was there supposed to be a footnote there? ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [March 29, 2019, 8:17pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/5 "2019-03-29T20:17:34Z")
They have way too much nitrogen when freshly chipped. Fresh wood chips from chipping or chainsaws left on lawns will kill the grass. It has taken me 4 years to get grass to grow well over the last chipped tree I had done. This is with hardwood trees, dunno about any other type. Dennis ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [March 29, 2019, 8:42pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/6 "2019-03-29T20:42:14Z")
> [@mixdenny](#): > > They have way too much nitrogen when freshly chipped. Fresh wood chips from chipping or chainsaws left on lawns will kill the grass. It has taken me 4 years to get grass to grow well over the last chipped tree I had done. This is with hardwood trees, dunno about any other type. > > Dennis The advice not to use it’s right, but the rest of this is actually backwards- wood chip is [low in nitrogen](https://books.google.co.uk/books?hl=en&lr=&id=uMIXAAAAYAAJ&oi=fnd&pg=PA1&dq=wood+decomposition+nitrogen&ots=633S9iUOBQ&sig=q_iKEd7XHgrwUf2zekauB68mmzg#v=onepage&q&f=false). The problem is that the bacteria and fungi involved in the decomposition process actually require nitrogen, more than is contained in the wood, in fact, so they temporarily ‘strip’ nitrogen compounds from the surroundings, and it’s this that kills the grass. If you want to use it, compost it for a bit first, ideally mixed up with something higher in nitrogen like vegetable scraps or grass clippings, which will help it decompose faster. If it’s really ground to dust, it should break down pretty fast. ---
**Author:** ![Allecher](https://avatars.discourse-cdn.com/v4/letter/a/a6a055/32.png) [@Allecher](https://boards.straightdope.com/u/Allecher)\ **Post date:** [March 29, 2019, 9:25pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/7 "2019-03-29T21:25:39Z")
In my experience the high spots of the sawdust start to pack down pretty quickly. You may find that in a month or so the area is level or even slightly below grade. As others mentioned it still probably won’t be amenable to grass growth yet. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [March 29, 2019, 9:37pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/8 "2019-03-29T21:37:48Z")
I’m not so sure about trees like the palms which might be quite shallow rooted, but in general, yeah, you’re going to eventually have a hole where the trees were. The more of the grindings you remove now, the more dirt you’re going to need later to fill them in. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [March 31, 2019, 5:57pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/9 "2019-03-31T17:57:22Z")
\*stay away from using walnut tree chips as mulch or a soil amendment unless you’re sure the plants you’ll be growing are not sensitive to juglone. ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [March 31, 2019, 6:45pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/10 "2019-03-31T18:45:53Z")
> [@Filbert](#): > > The advice not to use it’s right, but the rest of this is actually backwards- wood chip is [low in nitrogen](https://books.google.co.uk/books?hl=en&lr=&id=uMIXAAAAYAAJ&oi=fnd&pg=PA1&dq=wood+decomposition+nitrogen&ots=633S9iUOBQ&sig=q_iKEd7XHgrwUf2zekauB68mmzg#v=onepage&q&f=false). The problem is that the bacteria and fungi involved in the decomposition process actually require nitrogen, more than is contained in the wood, in fact, so they temporarily ‘strip’ nitrogen compounds from the surroundings, and it’s this that kills the grass. You are right, I actually meant to say high acidity, mainly tannins. Chainsaw chips will turn grass yellow in a day or two. Dennis ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [March 31, 2019, 9:14pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/11 "2019-03-31T21:14:25Z")
In my experience the people who grind stumps rake the remains smooth to make them fit in with the surrounding ordinary soil, as if they were soil. And that spot grows gigantic mushrooms for years and years. ---
**Author:** ![Grestarian](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/grestarian/32/3227_2.png) [@Grestarian](https://boards.straightdope.com/u/Grestarian)\ **Post date:** [March 31, 2019, 9:15pm UTC](https://boards.straightdope.com/t/stump-grindings-as-garden-soil/831728/12 "2019-03-31T21:15:09Z")
Wow! Thank you, everyone! You’ve actually answered my questions above, plus one that hadn’t even occurred to me. Q3: Can I plop sod down where the old trees were and expect it to grow? A3: No. The sod won’t be nourished and the grindings will eventually break down and leave a pit. So it looks like I’ll dig out the grindings, line the bottom of the ‘raised’ bed planter with it, and dump useful soil/fertilizer/ammend where I want things to actually grow. –G! Not that I’m closing this thread; feel free to chime in if you have more simple landscaping advice to add to this discussion.