a heavy flowering happens frequently with highly stressed trees.
A fruit is a seed. Maples produce seed. There is not difference except to the pallet.That's true.
But I'm not sure this is the only explanation for Acer palmatum, which is not a fruit tree.
I never said the tree was stressed. I only said that trees frequently produce extra seeds in relation to stress.@AlainK is right. Flowering of Acer palmatum is not always stress related.
JM flower on mature branch tips. You air layered off the mother tree's mature branch tips. This is why your air layer is flowering and the mother tree is not. It will take a couple of years for the mother tree to produce the branching for it to start flowering again.
@RKMcGinnis Trees flower on mature branches or on the tips of mature branches. When you air layered those branches off your 'Shishigashira' you took those mature branches that are capable of producing flowers. The mother tree now doesn't have the mature branches to produce flowers.JM flower on mature branch tips. You air layered off the mother tree's mature branch tips. This is why your air layer is flowering and the mother tree is not. It will take a couple of years for the mother tree to produce the branching for it to start flowering again.
I see this all the time when I air layer JM's.