How many tens of cubic yards are there? I had 60 cu.yds. of mulch delivered this year and it's really not a huge amount. If you have enough land to pile it up and ignore it until it decomposes that would be the best solution IMO. The goal would be to get it to decomp as quickly as possible with the least amount of work. Perhaps adding nitrogen as well as the leaves would help as you'd need as hot a pile as possible to get it to break down.

Anyone doing bulk composting in the area who will be interested in it? If so and you deliver it you might get some free finished compost in return.

Can you just leave it there as a beach stabilizer? Here the seaweed collects sand and nourishes beach grass, which helps with beach erosion. I don't know where on the Cape you are, but some areas are constantly fighting erosion.

Claire

We ended up renting a small backhoe and stacking about 15-20 yds of eelgrass, layered with whatever leaves we had, (couple cubic yards when compressed) and about 200 lbs of fish scrap 'strategically' distributed around the middle of the pile to provide some nitrogen. The pile is about 3x3x2(tall) yards and has been running about 100 deg, measured with a 20" thermometer. Animals don't seem to be disturbing it to get at the fish scrap, and there's no appreciable odor.
It'll be interesting to see if much decomposition takes place; if not, I have a source of summer mulch for quite a while.

I'd be interested as well in how fast eel-grass can break down in a pile like that.

If it's heating up, something is definitely happening. The big question will be how long it takes to become compost. Luckily it's fall so it will have all winter to slowly break down.

eel-grass, as we call it in the cape cod area, is wicked tough stuff. I have never had it in a such a large pile, but IME it takes a very long time to fully break down. So as I say, this will be an interesting experiment.

FWIW, I noticed our recent snowfall melted off the eelgrass pile; indeed, a temp check showed ~120F in several locations 20" inside. Other than the lack of snow cover, the pile looks pretty much as it did when we made it.

Ok, that's pretty interesting. it's cooking away. Don't forget to give a report at plating time as to the condition of the pile. Thanks...

Here's a late update:
The pile shrank to maybe 2/3 it's volume by springtime. Now, ~2 years later, there are still identifiable eelgrass chunks in it, but most are Only issue was a suspected N boon - I 've had lots of leafy growth and mediocre fruiting for the past couple years.
I'll definitely continue using eelgrass on the veg. garden.

josko, thanks for the follow-up. It's always good to hear people's long-term results. I do remember reading you original post and feeling jealous about you access to seaweed. It's supposed to have superior amounts of trace minerals that garden soils need.

Paul