As for fertilizers, I'll assume most come from manure *they try to get rid of it as much as possible, that's why spinach et gets salmonella (from poo).
Personally as I said before I grow as much as I can geographically and physically lol on my own. I compost our leaves & left overs. Haven't had to use poo and would be conserned about what the animals ate, what meds they were given et.
Personally as I said before I grow as much as I can geographically and physically lol on my own. I compost our leaves & left overs. Haven't had to use poo and would be conserned about what the animals ate, what meds they were given et.