Progression of Acer macrophyllum B

[MaciekA]

With the help of wind, my potted/boxed hydrangeas and strawberries managed to capture a few of these seedlings over the last 24 months or so. I've decided to see what it'd be like to grow them using colanders, later using colander stacking.

In the first year or two of watching them grow in their captured containers, I had a lot of trouble ID'ing them (I'm surrounded by various sorts of landscape maples that could have been the source of the seeds). This spring however, the foliage looked very different, and I searched around and eventually found this thread.

Your very first photo in the thread matches the juvenile leaf form I saw last year and the year before that. This year, my foliage finally looks decidedly like an Oregon Maple.

 

[parhamr]

It’s doing well!


This is from May 19. I’m pretty sure my water here is either more alkaline and/or has more dissolved solids than my last house. I have a water testing kit I need to use.

All that is to say this tree appears slightly chlorotic and needs a bit more acidic water and nitrogen.

I’m aiming to pump it up with quite a lot of fertilizer and defoliate it to encourage some more fine ramification.

Here it is in the middle between two of its three sibling trees in my garden

 

[MaciekA]

At what year did you start partially defoliating?

 

[MaciekA]

Also, I'm seeing nearly-identical discoloration on mine and am anxious to hear your results with increased acidity / fertilizer. I'm thinking I'm going to limit to fish fertilizer until summer starts to wane and if summer heat hasn't caused major issues by then, maybe add osmocote.

 

[parhamr]

At what year did you start partially defoliating?

This year! I’ve had them 9 years and they were each urbandori, so they are likely somewhere around 13 to 15 years.

Also, I'm seeing nearly-identical discoloration on mine and am anxious to hear your results with increased acidity / fertilizer. I'm thinking I'm going to limit to fish fertilizer until summer starts to wane and if summer heat hasn't caused major issues by then, maybe add osmocote.

I went a little heavy on cottonseed meal this year because I’ve heard it acidifies when it breaks down. I also applied two sprayings of liquid fertilizer this year and added an acidified to the concentrate. It worked pretty well!

Here’s the tree today


I’m forgetting what I had done to it this year. I know I defoliated its sibling trees

 

[Crazy Diamond]

Curious how the same tree put really small leaves in weak zones and gigantic ones in strong shoots

 

[parhamr]

Oh!! I forgot to post a water update.

It’s usually around 8.1 to 8.3 pH and the contents of dissolved solids (especially calcium and magnesium) is extremely low — to the point of barely being perceptible within the calibrated range for the test equipment. The total ppm is around 10-20, meaning it’s very soft water.

I am guessing this is softer than any of my previous homes, which explains the minor chlorosis.

It feels funny that I have to supplement to make things… normal

 

[parhamr]

I don’t love each of the primary branches. Some will continue to be replaced as sustainably as possible. The scaffolding for the next few layers of branching are underway…


The pruning to be done next May will knock back a few of those longer branches to their interior nodes.

 

[Crazy Diamond]

You defoliate them in late spring or summer?

 

[BrierPatch]

Thanks for all the progression updates! I like it, nice job! Not your usual maple you normally see. I just posted about one I have that I have in my yard, it's about 3-4 yrs old and was unsure if I should try something with it. Guess I'll give it a go, better than the waste bin.

 

[parhamr]

You defoliate them in late spring or summer?

It depends

Somewhere around the summer solstice works well, but the specific date deserves to be pushed around for weather trends. This year it was very hot in the mid and late spring, so I would have risked sunburn in May or June.

I did the full defoliation around July 6.

This species and this climate usually have a dry, Mediterranean summer of drought. They will definitely go into summer dormancy after the solstice, so I was careful to not wait too long.

 

[parhamr]

I think I’m approaching a more sustainable setup where I’ll have more balanced and controlled growth. This planting feels good.



I repotted it to allow more root growth — the prior pot was too small:

 

[greenguy]

This is really cool. I've been looking at all the Big Leaf Maples near the Sandy River where I live and wondering if it's possible. Thanks for sharing this

btw I love the term "urbandori" haha