Is Pond Weed Good for the Garden?

When we first came and viewed this property the pond was low and there was a white lacy looking substance on the ground around it.  I realized later that this was dried pond weed, and I wondered if it had any use.

Whenever the grandkids came over for a swim they had fun with all the tangled green stuff.  I got them and their dog to drag some of it to shore, and between us all, we left a small pile to dry in the sun.

Then I forgot about it.  Until today.

I was down at the pond checking the level, when I noticed a spot where the grasses were still green, and flourishing. 

 

The rest of the pond grasses were pitiful by comparison.  And right at the foot of the super grass was our pile of pond weed.

 

 I guess I'll be harvesting pond weed next year to use as mulch.

If anyone has experience with this stuff I would love to hear about it.