Usless coir rolls

I can but agree with T Lang about the uselessness of coir rolls fastened to canal banks, and concur that not only do they not stable banks, but do the opposite, and are pointless is providing habitats for insects as is claimed.

There was a long line of them installed many years ago along the Shropshire Union Canal, as all who have travelled that canal know is saturated with vegetation, but as the rolls fell away with the passing of boats those responsible would not give up so inserted a barrier at each end to protect the pathetic few that were left.

As can be seen from the photograph the bank here is sound and as can be seen there is ample foliage for insects, so I too ask, what is the point?

Jo Deaken