I live in rattlesnake country. As in literally up against PRIME rattlesnake territory. We also have several species of constrictors.
A snake that can kill a chicken (but not eat it unless it’s a <1# chicken) in our area would easily be able to get into any flexible netting. There is netting that is much thicker that’ll stop most larger/older snakes, but to stop almost any snake that would actually challenge a chicken you’d need a less than 3/4” opening that can’t be stretched.
Snakes can fit into the same hole that’s a rat (and sometimes mouse) sized hole.
That means for us the rules for rat proofing holds for snake proofing.
To keep our local snakes out of yards, they install a snake barrier that is at least 3’ tall with fencing that has a 3/4” or smaller hole that can’t distort.
I put 1/2” welded wire hardware cloth up 5’ (12” buried) and then put the 3/4” thick plastic bird netting the rest of the way up + the roof.
Electrified netting or a very low electric wire should work for snakes also. When there are other predators around, electricity can keep a lot of them away. That still means though that they have to touch the wire + a ground, so you still have to have really small holes down low, so as they try and go above it the hit the hit wire + still be on the ground.
Unfortunately if you’re talking about this:
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That’s simply not small enough hole (because it can distort. Think about what a rat could go through …
I used this on the roof of the hoop coop:
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But I also have 5’ walls of 1/2” welded wire hardware cloth.
YMMV, but in my opinion from someone in serious snake country—no, the bird netting that is used over trees will not work to keep snakes out.