What types of trees have roots that grow down, rather than out?

greengardener07April 14, 2008

I will be replacing a retaining wall in the near future. The current one, made of cinder block, is bowing as there was a lilac bush that was there for years before we moved in, and the roots made it bow out. So, that will go and a modular block wall will go in to replace it.

I want to put in a nice shrub/tree to anchor the planting bed which will be held back by the wall. The area gets full sun, especially in the afternoon. I was thinking of a Crape Myrtle or an Emerald Green Arborvite.

Any suggestions?

Thanks for any help!

Thank you for reporting this comment. Undo

None. All trees (and shrubs) have almost all of their roots in the top 20cm of soil, with only a very few special anchoring roots going deeper.


    Bookmark   April 14, 2008 at 3:47PM
Thank you for reporting this comment. Undo

So, I take it is only the "weeping" trees that have a tap root type system.

Resin, (or anyone will to chime in) if your were going to plant an "anchor specimen" 5 feet from a 3 foot high retaining wall (the top side of it, not the bottom), what would you recommend?

    Bookmark   April 14, 2008 at 8:06PM
Thank you for reporting this comment. Undo

There is nothing about a weeping tree that makes it have a taproot. Often, oaks, hickories, and such do have taproots, especially if growing in sandy or gravelly soil. But.........most of their roots will still be near the surface.

As to what to plant, give us a little idea of what growth form, size, etc you are after. There's a lot of trees out there;^)


    Bookmark   April 14, 2008 at 9:03PM
Thank you for reporting this comment. Undo

You may want to do some research into the crape myrtle. I've heard that they have roots similar to a palm's. I've heard it from a fairly reliable source, (it was in reference into fertilization), so you may want to explore that bit of info further.

    Bookmark   April 15, 2008 at 8:38PM
Thank you for reporting this comment. Undo

Palm roots actually can have a considerable spread - 30-50' from the trunk on well established specimens - so I'm not sure what relevance that would have in this situation. I'd also be interested on what basis the comparison of crape myrtle roots to palm roots was made, as other than the the crapes producing a very dense network of significant roots beginning immediately adjacent to the trunk and just below the soil surface, as do palms, I don't see much similarity. Palms have an ability to regenerate almost their entire root system, so can be transplanted with a minimal rootball of 12-18" surrounding the trunk. I'm not sure I'd recommend something quite so harsh with a crape of any size.

    Bookmark   April 15, 2008 at 9:31PM
Sign Up to comment
More Discussions
Who has snow?
Post your snowy garden pics. (Locally, almost none...
Help my dying tree it's leaves are drying
I found a dying tree and brought it home just to have...
2015 Midatlantic/SE/New England winter damage thread
I don't mean to exclude the midwest but I think for...
davidrt28 (zone 7)
Is this diseased?
This is a new young tree I purchased from Ebay. I planted...
where to prune these maples?
ugh what happened to GW?? anywho - need some advice...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™