> Your tree produces female flowers first and later in the year produces male flowers. This is to prevent self-pollination

How does this work in practice? Do other trees from the same species produce male flowers first, and then female? Logically, if all trees produce female flowers in spring and male flowers in the summer then the species can only survive if the seeds can remain viable unfertilized for months (which is probably not that exceptional for plants, I wouldn't know). But if the female seeds are still viable by the time the plant sprouts its male flowers, exactly how does this prevent self-pollination?

Actually I just looked it up and they're more bizarre than I thought. They are actually "protogynous". Meaning all flowers start off as female and as they mature they turn male.

I should've just said "later" instead of "later in the year"

I'm not sure how long pollen stays viable in the environment. Some species can stay viable for many weeks but most are just a few days I think. They can stay viable for years if refrigerated properly however.