i edited a little before you quoted:
"you can definetly grow thoose seeds and get enjoyable weed to smoke."
having enjoyable weed to smoke is my point mostly i don't care about a few ball or seeds if the weed still taste good enough and is potent enough. i m not advising to breed those seeds over many generations. just saying that first generation of hermie is still good enough to grow eventually and enjoy.
concerning my case i suppose little airflow and low light penetration bottom of the canopy cause a few single balls to pop on preflower nodes the first few weeks of flower, happen with a few strain not all, and never all phenotypes, from one to half a batch of seeds usually.
also some landrace strain like marrocan beldia and some other strains are known to carry the hermie trait more than some others.
Thats fine, just know if you keep regrowing succesive generations of those seeds, that trait will become more prevelant over time. It does with all hermies tbh, just with some to a higher degree then others and bare stamen will become balls will become fully formed male flowers with inbreeding those genetics, thats just how that works. Some land races have a higher chance of hermie, because their initial lineage that form,ed the land race was less diverse (i.e. more inbreeding) If the plants get as far as making full male flowers down low, you need to trash that lineage. Seriously. Not doing so, across a large scale, is is currently happening, can genuinely damage the future genetic potential of the plant we love so much.
And also, if your fem seeds are doing that, full male balls already, the plants used for the cross were not stress tested phenotypes. And were likely multiple inbred generations using entirely untested female plants for hermie pollen. But that being said, sometimes the best smoking plant out of a bunch just spits some bananas sometimes too, so thats the plant you run with. But unfortunately, breeding exclusively for things like potency and bag appeal, is also currently destroying the quality of cannabis genetics as a whole as well, entirely in the name of proffit margins.
If your plants are making fully formed balls, your only a few gens away from a ruined lineage that produces full formed flowers down low, genuinely may be as low as a single inbred generation away from it, can confirm from multiple experiences over the years. I havent seen anything but bare stamen on fem seed myself in years... On my wn fem seed i havent even seen that.
If you have anything more then that, you should definitely trash that lineage, or at the very least run a hepa filter so you arent putting that pollen out into the atmosphere. Growers making careless decisions with inbreeding and running monoculture crops... Ive been watching the same mistakes get made over and over for a couple decades now, and thse mistakes were being made before i even existed, and people still dont wanna learn from them just because the easy way forward is easiest lol.
If you dont want hermies, put the necessary work into making fem seed yourself, find a truly reliable breeder, or grow regular seed and pull the males out. Really all you can do. If you have plants that hermie easily, i strongly recommend you avoid growing that seed as well. And if you do, and live in a neighborhood or near other properties, please just be respectful to other potential growers, and put a hepa filter on your exhaust
And do not put those plants outside to grow. Please. that stuff can spread literally miles at a time. There's a grower on just about every neighborhood block these days in some places.
Fast and loose in the name of proffit and self satisfaction with plant genetics is very unwise. Ill stop rambling at one phrase: "I wonder what the gros michel tasted like... ill never know..."