For the past two years, I collected Trident Maple seedlings and placed them in one-gallon containers with nothing but (Fir) bark (a few pots had Perlite, most did not). These plants have done remarkably well. In late Winder/early Spring, I moved them into a Bark, Pumice, Perlite mix. I haven't lost a Maple yet.

Josh

I'm glad to see you used pumice in your mix. Pumice is God made. It has nutrients, as opposed to Perlite/Vermiculite, but it has the same characteristics of providing excellent aeration to the soil, and loosening heavy clay soil and at the same time, it retains moisture well. Where I live, Pumice is cheap compared to the alternative, and a whole lot nutritionally better!!

There should be a glut on the market soon for Pumice. That big volcano in Iceland? wherever, is putting a lot of it out!!

Pumice is insoluble rock, so it does not provide any nutrients, but it is a great amendment for drainage.

Thanks for the feedback. So it sounds like maples can be grown in pure pine bark. I might try this and see what happens.

Josh, do you screen out the fines and large pieces when growing your maples in pure pine bark or just leave the fines and all in there? Also did you fertilize the maples or add lime to the pine bark when planting?

Thanks.

For the maple seedlings, I used a 3/8 inch screen - and I kept everything that fell through.
If the pieces are too large, I find that the bark/mix dries out too quickly/unevenly.

I did not lime the bark the past two seasons, but I did fertilize with Osmocote 4-month.

This year, my collected Maple seedlings are in bark, perlite, and pumice - with Osmocote
and firewood ash added to the mix. I also fertigate with Foliage Pro 9-3-6.

Josh