I think you have to grow large internode/leaf acers in pots from early on to properly get the reduction required to be worthwhile specimens. My silver maples grow large leafs but the first leaf pair is usually small. You need to create ramification first early on so that you create enough budding points to distribute high energy trees' vigor after pinching and pruning. Use sacrificial branches as energy drains from other parts of tbe tree. Leaf cut and reduce photosynthetic material... Ryan Neil's theory of "gas pedals" if you will.
Yeah, bredda. I understand ramification on a cellular level.
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I was not trying to belittle AT ALL! I'd be proud to have some beefy ass Acer specimens like that!
I literally mean... I've grown enough from seed to know the numbers vs. what I am personally aiming for trait wise. I WANT to be able to "select"!
300-500 seedlings observed each year for a few now. Weeded down (yearly) to about 12-20 decent for bonsai. (Some others to landscape, but not many, most planted out on public lands)
The rate of "desirable" is much higher on Tatarican. As I imagine some of the other "usual suspects" are.
Like I said, all WILL reduce...
I just happen to know, regarding Silvers Reds and Freeman's.... You watch hundreds of seedlings to get those nice tight internodes and small leaves (off the "bat").
Now, regarding Silvers, Reds and Freeman's and planting 800(or so) seeds at a time, a decent amount (like another 20-25) normally end up in the 'medium range' which will reduce very nicely.
Hell! Even the huge leaf/long internode specimens will reduce reasonably with a touch more finesse... A guy in GB swears by tegmentosum... He gets 'what he is looking for"
I just really like the first 3 years of a trees life. And am obsessed with Acer genetics/traits.