Given that those seeds are packed with nutrients, everything the seedling will need once it germinates and starts to grow, I would think of them more as a "green" and not a "brown".

Agree with kimm -- C:N ratio of the total "maple copter" is about 9:1, so a green.

Here is a link that might be useful: Analysis and Composition of Silver Maple Seed

This post was edited by TXEB on Fri, May 17, 13 at 11:38

I would definitely compost maple seeds, and have done so in the past.

I was thinking that seed should be high in N. Well, meanwhile, the compost is going gangbusters and is not smelly and manure-like as it gets with too much grass clipping greens. Maybe the wings give some brown.

It's all in the C:N ratio.

Wings (perciarp) are brown, ~39% C, 1.3% N, C:N ~ 30. The seed is ~4.4% N (from 27.5% protein content) and ~ 29% C; C:N ~7. The seed represents ~70% of the "copters" weight, the wings only ~ 30%, so the seed wins.

Just realized I had an error in what I said previously - the C:N ratio for the total "copter" is more like 9:1 (corrected).

This post was edited by TXEB on Fri, May 17, 13 at 12:09

It dawned on me that until the seed coat is broken, a maple seed will probably behave as a brown material in composting. I believe most of the protein (and N) is inside. So unless the seed opens or the coat is decomposed, then it's a brown. If/when the seed interior is exposed, then it's a green.

Thank you so much TXEB. That was very precise info. Where do you get it?

The pile is still hot and not slimy. I'm pleased.

I calculated the %C and %N for each of the two phases using the analytical data from the paper I referenced above, and then weight average for the total using the 70:30 ratio from the papers analysis of the composite seed. Sugars are ~40% carbon, crude fiber (lignin) and crude fat are both ~ 62% carbon, and the nitrogen is given.

Sorry, didn't see the reference in your first post.

That article is a fascinating piece of history, besides the still-valid science, I assume. Did you see the date on it?!

Thanks for contributing your expertise and calculations. There are such amazing people on these forums.

The compost is still steaming along.

It was a very interesting motivation to do the analysis. In my experience the old analytical work (pre-instrumental days) was some of the nest.

I'm curious, have any of the seeds broken open?

I'll check. Those that I swept up from the street had many open seeds already (from foot and car traffic), though, so it may not be so simple to know what's happening.

Here's what I found. The seed coating seems to be decomposing rapidly. The inner seed that had been fat and bright green is now flat and black-ish green. Progress, I would say!