This is the alligator weed in 2007 in the lake on the right side of 5. If it is left unchecked it can take over an entire lake causing it to be aesthetically upleasing and causing problems for the wildlife that inhabits it.
The crew uses 36" landscape rakes with ropes tied to the handles. They throw them in the water past the alligator weed and then pulls it back to the bank so it can be removed.