I'll add that I posted this question several days ago, and it disappeared several times because someone flagged it as having "inappropriate content". Somewhat delusional, but ... Thank you to Houzz for replacing it.

"The question is, how do you most effectively store viable squash pollen?"

"So at the end of the season, one ends up with squash with a half-dozen female flowers and NO male flowers."

No, the question is why would you want to? What would the purpose be, outside of a purely academic exercise? It's the end of the season -- you're not going to get any more squash to ripen.

(BTW: I did notice your post disappeared, I thought it was you who deleted it. That is odd - I've seen inappropriate things on these boards, this ain't it LOL!)

The reason I'd like to know was expressed in my original post. First paragraph. I DID have female flowers with no male flowers. Yes, where I live, one CAN harvest squash through out the winter, with some luck. I've done it. We get freezes here about half of all winters. As it happens, I just got one the other day, and the squash are gone, but, that's the breaks. No luck this year. But an answer to my question would be useful for other years.

Also, I frequently hear about people with small patches, who just don't have a lot of flowers. Statistics being what they are, you can easily have a crop of a few female flowers with no male flowers.

Easy peasy,all you need is cryogenic equipment.

Out of curiosity I did a quick search and freezing seems to be the answer. Lots of hits on Google.

Yes, if you look in the right place, there is some advice about saving pollen for various other plants.

https://forums.botanicalgarden.ubc.ca/threads/pollen-how-to-store-them.62962/

https://ecosystems.psu.edu/research/chestnut/breeding/pollination/male-flowers

Freezing does seem to be the answer for long-term storage, but one repeated caution is not to allow moisture to contact the stored pollen. Dessicant is advised, though once you're in the freezer, the dessicant won't do much.

But one reference suggests that for cucurbits, it isn't easy, but maybe storing a male flower overnight in the fridge the day before it completely opens can work. That involves some tricky timing, because you have to predict when the female flower is going to be receptive.

https://cucurbit.info/1983/07/influence-of-temperature-and-humidity-on-longevity-of-squash-pollen/

Somewhat puzzling that there is so little consensus about this.

I never thought about trying to extend the life of the pollen, I just harvest the flowers and eat them 😀

Flowers are tasty, but squash are nicer. I grow squash for the fruit, not the flowers.

I like both.