Paperbark Maple - Acer griseum

When I posted about partial defoliation of my paperbark maple in the Defoliation thread @Anthony suggested that the species might be worth its own thread. The peeling bark is a real asset, but the large internodes, petioles, a leaves will take some work. I am kicking this off with pictures of mine which I bought as Nursery stock at a convention in Victoria, BC in 2004. I think I am finally getting some of the tools and techniques to bring it along as a bonsai rather than a tree in a pot. The best one I have seen belongs to David DeGroot and when I asked how he got his to have small leaves he said treat it like any other maple - build it up and cut back and defoliate.

A bushy and not great focus picture from Sept. 2018.

I fertilized reasonably (not a great build up) and did a fairly hard cutback and near full defoliated in May/June 2019. I got a fair bit of back budding and here is an image from April 2020 just before I repotted where you can see some twigs developing.

I had managed to develop a decent root pad during those years as a tree in a pot which is starting to merge with the bulge at the base.

I did a partial defoliation by a mixture of cutting off one of the leaflets and cutting others in half after the partial defoliations streams in May/June 2020. I also cut some of the branches back completely if I saw buds.


I got a fairly good response with new, smaller shoots on the lower branches, but not as many in the apex. Here are pictures from August 2020 of the tree and some of the new leaves. Some are full sized while others are much smaller.


I am hoping to get more, smaller leaves and internodes as I continue to fertilize consistently with a good organic and use partial defoliation to build the number of twigs and leaves.

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Looks great! I tried collecting seeds from some landscape griseums at my work a few years ago, but none sprouted. I hear most seeds are not viable :frowning:

Since it’s a trifoliate leaf, how did you do the partial defoliation? Take off two of the three leaflets, or did you cut each leaflet?

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I agree the germination rate is low. That is why I collect the seedlings from under the tree in my yard. I am guessing the germination rate is well under 1% in that situation.

I did a mix of partial defoliation methods on the trifoliate leaves. Sometimes I cut out the largest leaflet and cut the others back a bit. Other times I cut all three back by about 2/3. I have also done this will a box elder (Acer negundo) seedling that I have been growing in a pot for a decade because it had a nice textured bark. Still a very coarse tree, but smaller leaves and internodes than the one in the yard.

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That is…amazing! Never seen a paper bark maple before. Super dope. Reminds me of river birch without the merciless and sudden branch die-off.

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Great thread, thanks for the detailed post. This will be a helpful reference. And will temper my expectations when I collect seeds from the trees near my house lol.

Just collect a couple of hundred to put the odds in your favor :laughing: