Can't find much information about this species... What I do know is:
Grows very fast, 2-3 flushes of growth in warm climates.
It produces juvenile foliage when it's young or stressed. This foliage has a lighter color and the needles are very short. I've noticed that on my tree the mature foliage has two needles per fascicle. The juvenile foliage has only one needle.
The longest needles are 6 cm, the shortest (juvenile) needles are 1cm long.
BUT at the top there are mature needles (2 per fascicle) that are only 1.5 cm long! These are probably from the last flush of growth. Also, at the top there is more light => less stress => more mature growth. And of course apical dominance bla bla...
In conclusion: the tree can produce short, mature needles, yay! I've read that once the tree is set in its basic shape, you should treat it like a Japanese red pine. Now, I don't have any experience with Japanese pines, so I don't know what that means (yet). But I'm going to make a wild guess and say that it has something to do with decandling during the summer. (?)
Now some more pictures of my little friend:
The base, again, in daylight:
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I'm probably going to repot it next spring. The soil looks like it has seen better days.
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Long and short mature needles:
View attachment 168384
Juvenile needles. You can see 4 (2x2) 'mature' needles on this shoot as well.
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And as
@milehigh_7 said, they backbud quite well!
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