Will burying already established nebari rot the bark?

[Rodrigo]

I just purchased a new elm that already had relatively okay nebari, but had some gaps where there were no roots. I repotted it yesterday and saw some new roots forming in the gaps, so I ended up burying the nebari a bit more than I would've otherwise and added a thin layer of sphagnum moss.
After I was done though, I got to thinking that maybe I shouldn't have because the nebari that was already there had formed a bit of bark on them. Will the bark on the newly buried roots rot by the time I repot again? I couldn't think of any other way to make sure the new roots survive than burying it.

 

[BobbyLane]

I just purchased a new elm that already had relatively okay nebari, but had some gaps where there were no roots. I repotted it yesterday and saw some new roots forming in the gaps, so I ended up burying the nebari a bit more than I would've otherwise and added a thin layer of sphagnum moss.
After I was done though, I got to thinking that maybe I shouldn't have because the nebari that was already there had formed a bit of bark on them. Will the bark on the newly buried roots rot by the time I repot again? I couldn't think of any other way to make sure the new roots survive than burying it.

If its a smooth barked elm I wouldnt worry much

 

[Leo in N E Illinois]

Buried bark on roots can rot, but usually if one needed to bury the nebari, it was important for the health of the tree. As the nebari is exposed later, bark will redevelop, and there will be somewhat better equalization of bark texture between older and newer roots as nebari is re-exposed. So the loss of bark while buried is not necessarily bad, if one wants new roots to match older roots.

 

[Shibui]

Only the outer layers of bark will rot. Trees know how to change to suit conditions so the buried roots will just be roots. If this was not the case there would be no trees left on floodplains where soil levels change every few years after flooding events.
If roots rotted when buried ground layering would not be recommended either. Or air layering or cuttings which all rely on previously above ground bark being subjected to constant dampness.

Planting deeper as you have done is the sensible approach to promote more roots and enhance the current nebari.

 

[Rodrigo]

If its a smooth barked elm I wouldnt worry much

It's a siberian elm so it does have a bit of bark but nothing like a full on right bark. Thanks Bobby! I appreciate the input

 

[Rodrigo]

Buried bark on roots can rot, but usually if one needed to bury the nebari, it was important for the health of the tree. As the nebari is exposed later, bark will redevelop, and there will be somewhat better equalization of bark texture between older and newer roots as nebari is re-exposed. So the loss of bark while buried is not necessarily bad, if one wants new roots to match older roots.

That's a good point Leo, thank you! It definitely needed it for the health and asthetic of the nebari as it had quite a a large gap between roots. I did try to al least keep the sphagnum moss a bit separated from the trunk so that's not causing a problem with the trunk bark.

Only the outer layers of bark will rot. Trees know how to change to suit conditions so the buried roots will just be roots. If this was not the case there would be no trees left on floodplains where soil levels change every few years after flooding events.
If roots rotted when buried ground layering would not be recommended either. Or air layering or cuttings which all rely on previously above ground bark being subjected to constant dampness.

Sorry, to be clear I did mean just the outer bark rotting- it makes sense that the roots themselves will be okay but I appreciate the input anyways! You do make good points though glad to hear I did the right thing!

 

[Vincent Tanner]

Buried bark on roots can rot, but usually if one needed to bury the nebari, it was important for the health of the tree. As the nebari is exposed later, bark will redevelop, and there will be somewhat better equalization of bark texture between older and newer roots as nebari is re-exposed. So the loss of bark while buried is not necessarily bad, if one wants new roots to match older roots.

Sorry to “derail” the thread a bit, but I have a related question— will bark reform on the nebari and trunk if the tree was rot damaged from moss staying on too long? I removed a lot of moss from a Chinese elm and have some rot/damaged bark.

 

[Leo in N E Illinois]

Sorry to “derail” the thread a bit, but I have a related question— will bark reform on the nebari and trunk if the tree was rot damaged from moss staying on too long? I removed a lot of moss from a Chinese elm and have some rot/damaged bark.

Yes, bark will reform. It will start reforming the minute you get the moss off. HOWEVER it can take years, several years at least and with exhibit quality trees it can take a decade to repair the visual damage that moss does to the bark. It will take a long time for the reformed bark to blend into the bark above where the moss grew. For this reason, it is important to keep on top of removing moss from trunks, especially on older trees with better developed bark. One summer with moss can leave a visual mark that takes several years to get rid of.