I am a newbie since I have only had my hens since August but I have learned on some old forums from people on this one that all hens have worms. But a natural worm preventive that some others & I use are pumpkin-cucumber-zucchini-squash seeds & cayenne pepper flakes. The veggies they get all winter and as they grow from the garden. The cayenne pepper flakes I add once a month or so to their FF. I can say that I have never seen an overload of worms in my hens poop ever. I believe prevention is better than treating a problem.
How old do they need to be before adding the pepper flakes & do you just sprinkle on top of their food or mix it in?
Definitely adding the above to my chicken's dietary repertoire!