Problem with unbalanced cedar elm

[Michael P]

I originally posted this in Markscott's excellent new thread on defoliation. It was a bit of a hijack and never received a response, so I'll it a separate thread.

This year my cedar elm just began to leaf out and immediately developed a massive scale and mealy bug infestation on the lower third of the tree. I've never seen anything quite like it. I got it under control with a combination of physical removal, soapy water spray, and a systemic insecticide. The tree now appears pest-free.

The top two thirds of the tree are growing strongly, but the bottom third never fully recovered. No branches died, but all have very sparse foliage. I have been fertilizing and letting the tree grow freely to regain strength. But the top is dense and the lower branches are not catching up.

Should I let the tree continue to grow freely this year, or should I prune or partially defoliate the top to redirect energy to the lower branches? This tree is a collected specimen that I styled in a workshop with Nick Lenz, so I really don't want to lose it, damage it, or have to redesign it.

I'll post some photos later today.

 

[coachspinks]

I have one cedar elm. It too was top heavy. I have kept the top cut back and it is putting out new growth in several spots on the trunk.

 

[Forsoothe!]

I Don't know anything about these Cedar Elms specifically, but if you let any deciduous tree lower limbs get shaded out for any reason, they will shed those lower branches because that's the normal process. It doesn't matter why it happens, only that it starts and the normal process of growth is to support what has good light and conditions and shed all others. I say defoliate the top, fertilize, and favor the lower branches by not allowing the top to grow as dense as it might until it gets back into balance. In fact, never let the top get too dense, or else. Remember, triangular shapes actually work.

 

[penumbra]

I would like to see a picture but my gut instinct would be to judiciously prune the top back to redirect some of that energy to the bottom branches.

 

[markyscott]

I originally posted this in Markscott's excellent new thread on defoliation. It was a bit of a hijack and never received a response, so I'll it a separate thread.

This year my cedar elm just began to leaf out and immediately developed a massive scale and mealy bug infestation on the lower third of the tree. I've never seen anything quite like it. I got it under control with a combination of physical removal, soapy water spray, and a systemic insecticide. The tree now appears pest-free.

The top two thirds of the tree are growing strongly, but the bottom third never fully recovered. No branches died, but all have very sparse foliage. I have been fertilizing and letting the tree grow freely to regain strength. But the top is dense and the lower branches are not catching up.

Should I let the tree continue to grow freely this year, or should I prune or partially defoliate the top to redirect energy to the lower branches? This tree is a collected specimen that I styled in a workshop with Nick Lenz, so I really don't want to lose it, damage it, or have to redesign it.

I'll post some photos later today.

Many apologies - I’ve been having significant connection problems. I would not recommend defoliating the crown. Keep the new growth under control by pruning lightly, but do not defoliate. It may take a season or two for the lower branches to regain vigor. Next spring, I would thin the top and leave the lower branches more full.

- Scott

 

[Michael P]

Scott, no apology necessary! There was a lot going on in your thread. I am going out to take photos of the cedar elm now.

 

[Michael P]

This is a photo of the full tree.

 

[Michael P]

The vigorous top:

 

[Michael P]

The middle third:

 

[Michael P]

The weak bottom third:

 

[Michael P]

A close up of a badly affected bottom branch. You can see buds that began to swell in early spring, but stopped, then aborted, and are dead now. To my eyes the tree looks worse in person than it does in the photos.

 

[BobbyLane]

good thing about elms is you can cut back hard into old wood and they will generate buds on bare branches.
this is just a matter of doing that all over, but much harder in the top and middle.

 

[Bnana]

Isn't that branch simply shaded by the branch above?

 

[Michael P]

A few general notes: The tree was repotted in late winter as it had become root bound and drainage was suffering. I normally prune the top of the tree much more then the rest to maintain balance. My main question now is whether it will help to prune and/or partially defoliate the top to redirect energy to the bottom third? Or should I simply let all of it grow for the rest of the season?

 

[Michael P]

Isn't that branch simply shaded by the branch above?

It was strong last year, and I did the normal amount of pruning above it early this year before the pest explosion. This loss of foliage and aborted new growth is something that I've never seen before.

 

[markyscott]

I’d do some light thinning near the apex, but other than that, I’d let it go. Think about where you want to take this tree. A lot of the lower branches are thick, but not particularly interesting - they’re straight, without branching and they don’t exhibit much taper. If you like the tree as is, it’s not a problem. If it were mine, I’d be looking to correct that issue and it would make a difference for what I would be doing now.

 

[Michael P]

Thanks for all the replies and suggestions!

Scott, I am fairly happy with the tree as it is, but please tell me waht you have in mind. My first priority this year is restore the health of the tree, but I might be up for changes next year.

 

[markyscott]

Thanks for all the replies and suggestions!

Scott, I am fairly happy with the tree as it is, but please tell me waht you have in mind. My first priority this year is restore the health of the tree, but I might be up for changes next year.

If it were mine, I’d consider starting over. As I did with this Cedar Elm. If you like it as is, you’ll need to strengthen the lower branches. I’d do this by thinning the apex and controlling the growth there this season. You could leaf thin, but I wouldn’t completely defoliate the apex.

Scott

 

[Michael P]

Thanks again! I will study your elm progression in detail as a possibility for next year.

 

[ConorDash]

Balancing of energy in a tree:

Defoliation on Elms (and a lot about balancing of energy too):