I am trying to hybridise alnus species. I am using A. glutinosa to
pollinate other species, eg A. cordata. For alders which flower near
together this is not a problem. For alders which flower earlier than
A. glutinosa,I cut A. glutinosa twigs and bring them into the warmth
of the house, they produce pollen earlier than they would have done
and I use them on the target species. For species which flower later,
I put A. glutinosa into the fridge to hold them back... .

But I can't see this working for species which flower MUCH later,
after the leaves come on. Are there ways round this?

Michael Bell

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