# Burying tree trunks **URL:** \ **Category:** Factual Questions\ **Created:** [October 7, 2015, 4:32pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826 "2015-10-07T16:32:34Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [October 7, 2015, 4:32pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/1 "2015-10-07T16:32:34Z")
This is hypothetical. I’m not actually going to do it. Every so often I look out at the back yard. It slopes from left to right, and it slopes from the house for about half of the property before dropping off sharply to a little creek. ‘Wouldn’t it be nice,’ I think, ‘if I could put a retaining wall at the drop-off and level the rest to make it more usable?’ The thing is, there are several nice cedars that provide shade (the sun is often low here) and shield us from high winds. Suppose I put in a retaining wall and levelled the ground. The trunks on some of them would be buried six or eight feet. Would the trees survive? ---
**Author:** ![TroutMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/troutman/32/6721_2.png) [@TroutMan](https://boards.straightdope.com/u/TroutMan)\ **Post date:** [October 7, 2015, 4:47pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/2 "2015-10-07T16:47:21Z")
It would eventually kill the trees. The shallow feeder roots need access to oxygen and nutrients, and the additional depth would hinder that. Some trees will put out new roots from the now-buried trunks, but these can strangle the tree as they get bigger. Here are a couple links about it: [http://www.thetreetender.com/Soil%20Level%20For%20Trees.html](http://www.thetreetender.com/Soil%20Level%20For%20Trees.html) > **[Mulch Can Kill Trees](http://www.coldclimategardening.com/2011/11/14/mulch-can-kill-trees/)** > > Mulch can kill trees–that sounds kind of extreme, doesn’t it? But it caught your attention, right? I suppose it would be more accurate to say improper mulching can kill trees, but as I … ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [October 7, 2015, 4:55pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/3 "2015-10-07T16:55:51Z")
Probably not. While many can survive some additional soil added to the top, the roots need air to operate correctly and that much soil would smother them. What you could do though is to build [circular retaining walls](https://www.google.com/search?q=retaining+wall+around+oak&biw=971&bih=646&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMItZfO6-iwyAIVxhseCh2Awwcn#tbm=isch&q=circular+pit+hole+retaining+wall+around+oak&imgrc=Na7Ubn0CFx-K3M%3A) around their canopy perimeter that leave them in a sort of pit and that might work. I’ve seen that done with oaks, probably need to investigate further if it’s been done successfully for cedars as well. Another consideration, do like the Incas and [terrace](https://www.google.com/search?q=retaining+wall+around+oak&biw=971&bih=646&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMItZfO6-iwyAIVxhseCh2Awwcn#tbm=isch&q=circular+pit+hole+retaining+wall+around+oak&imgrc=KyaNnaghOk411M%3A) the slope while maintaining the original elevation where the trees are. ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [October 7, 2015, 5:26pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/4 "2015-10-07T17:26:50Z")
Seconding the retaining wall idea. My father did this for a tree in our yard back in the 60s, and last time I checked it was still there and healthy. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [October 7, 2015, 5:41pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/5 "2015-10-07T17:41:57Z")
> [@lieu](#): > > What you could do though is to build [circular retaining walls](https://www.google.com/search?q=retaining+wall+around+oak&biw=971&bih=646&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMItZfO6-iwyAIVxhseCh2Awwcn#tbm=isch&q=circular+pit+hole+retaining+wall+around+oak&imgrc=Na7Ubn0CFx-K3M%3A) > [@silenus](#): > > Seconding the retaining wall idea. Just to be clear, I’m not going to level the back yard. I was just curious. ---
**Author:** ![Renee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/renee/32/287_2.png) [@Renee](https://boards.straightdope.com/u/Renee)\ **Post date:** [October 7, 2015, 6:18pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/6 "2015-10-07T18:18:53Z")
Some years ago when we lived in a neighborhood, one of our neighbors built a flower bed, maybe 18" deep, 8’ diameter, around a big old tree. It killed it within a few months. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [October 7, 2015, 6:58pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/7 "2015-10-07T18:58:48Z")
You can let a tree grow in a well, but 8 feet is pretty deep. Just snake the wall around the trees at the bottom of the slope and maybe you could use wells for some half way up that wouldn’t be so deep. ---
**Author:** ![Cabin\_Fever\_1](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cabin_fever_1/32/2908_2.png) [@Cabin\_Fever\_1](https://boards.straightdope.com/u/Cabin_Fever_1)\ **Post date:** [October 7, 2015, 8:23pm UTC](https://boards.straightdope.com/t/burying-tree-trunks/733826/8 "2015-10-07T20:23:03Z")
I just woke up from a nap and as usual headed for SDMB GQ and parsed this thread title as “_Buying tree trunks_”. I chuckled to myself, “What is **Johnny L.A.** up to now?” I even had a factual answer for said question. 😃