It looks like mostly like a thick crop of Chara - technically an advanced form of algae. For irrigation consider using several grass carp per acre and some tilapia. Both will eat Chara. Amount eaten depends on how many fish you add per acre. You may need to do some significant removal of the Chara prior to adding the fish so they can sooner get ahead of the weed.

Last edited by Bill Cody; 09/11/15 07:57 PM.

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