You can, but you might be happier just saving them for seed.

They are growing next to bush beans, any chance of cross pollination?

not much. beans are pretty self-contained

Thanks. I guess if they were cross pollinated the seeds would probably look different.

Actually if they're crossed the seeds will look the same, and you won't find out until you plant them the next year (unlike with corn). There is a chance of cross-pollination but it's small. If you live in a hot dry area with lots of bumblebees and carpenter bees you'll get a small proportion of crosses, but in other climate/bee regimes it's rare to unheard-of. At the Bests' farm in Kentucky their rows are only 2 feet apart and they basically never get a cross, but if I do that I get 1-10% crosses. Some bean varieties are reported to cross much more readily than others as well, mostly big-seeded old types. I've seen Goose, Jeminez, Blue Shackamaxon, and Ma Williams called out as being free with their genes.

Thanks. I have plenty of bumblebees and carpenter bees. But if the chance is small, could be a fun surprise for a few seeds.

Fortex would be less than ideal as a dried bean, but you could use them that way. I harvest all of my immature beans every year just before frost, and use them as shellies... which IMO is better than giving them to the frost. Waste not, want not.

Thanks, zeedman, I had quite a few green beans go past their prime this year so that's a really good solution. I'm guessing that would hold true for most green beans? (lookin' at you, Grandma Roberts.) I planted way too many green beans this year and, of course, you can never have enough shellies.