I have a Taiwanese or Formosan Trident Maple which is covered in seeds, I would like to sow them but I need to know first when are they ripe? Second when and how to sow them? I have searched around and the information tends to be contradictory. I tend to think they have to stay on until early autumn, and to be sown straight away. Opinions gratefully received.
Geoff

What does nature do? Seeds fall off in autumn, lay in/in the ground through winter and they sprout in spring.
So, collect them in autumn, place them in a seed tray, let them stay outside during winter ( maybe covered a bit if you have winters of -30 during 4 months...) and watch them grow in spring

Yes, I have been doing some research and Taiwan is generally not cold, apart from mountains. They do grow by the roadside, and in Teipai which is temperate. I will leave them on the tree until autumn