What about bird netting? I have read they will get caught up in it. You can then cut it out and relocate the snake. We have black snakes that reside near our chickens, and I was planning on trying it this year. Just haven't implemented it yet (or seen a snake for that matter). They tend to come from under our shed which is about three feet from our chicken run. This year we've noticed a bunny living under there. I suppose that if any snakes were there they would eat the rabbit?
Anyhow, the plan was to skirt the shed with the netting.
Anyhow, the plan was to skirt the shed with the netting.