I’ve been considering their use for a number of things too:
1. as a swale alternative
2. at the ends of swales to redirect water to drainage ditches
3. to line the bottom of drainage ditches: erosion control, but also to act as low flow control devices that permit water to flow unseen at the bottom of the ditch and not have it laying in pools like a stagnant creek e.g. mosquito control
Though the ones commonly available here, used by different Government Departments during road construction for erosion/silt control, are made from coir – coir logs. (Government is required to jump through lots of environmental control hoops, so they must be safe to use and function to set specifications.)
However, at the moment, they are prohibitively expensive given their relatively short lifespan.
There are lots of weasel-words used to sell stuff as ‘environmentally friendly’ – if it’s synthetic cloth it’s likely to break down to nano-sized bits of plastic that are significantly worse for the environment. If it’s a natural cloth fibre like hessian, calico, etc then that would be a better alternative.
I have had good luck using woodchips, branches, hay, or a combination to filter water and catch sediment. All of which add to the fertlility as they break down. I see no need for it in my rural setting.
Can you get your hands on some hessian (jute) fabric? I plan to start making bags out of this stuff and filling them with biochar for sediment traps which will also grab soluble nutrient loads from waterways.
I think it is probably worth mentioning that if the silt socks were filled with a woodchips or straw material they can be used to grow mushrooms on. The applications I have read about mention oyster or wine cap, pretty sure that was trad cotter's book. Though I suppose that is more an applicable function stack not necesarilly a reason on its own.
Organic Mushroom Farming and Mycoremediation: Simple to Advanced and Experimental Techniques for Indoor and Outdoor Cultivation https://www.amazon.com/dp/B00X6D9T78/ref=cm_sw_r_cp_apa_bR91BbF65CQPF
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