Grass and Leaves

Why is it that dried leaves are considered browns, but dry grass is considered greens?

Grass is high in nitrogen, even when it's dried (think of hay). Dried leaves are not.

At least, I think that's why! Feel free to correct me, anyone...

I believe it's the Nitrogen content. Those items that contain high amounts of Nitrogen are generally considered to be "greens" while those that are high in Carbon are considerd to be "Browns".

Okay, usually this kind of information sends me out on the web to try to figure out : WHY? But I tried that and there are way too many false threads to follow so next question is:

Both leaves and blades of grass perform the same function, photosynthesis, for the plant, so what makes them different?

Difference is how, why, when it was removed from the plant. If the grass way cut from a live, growing, green lawn, it's a green. If grass dies from drought, disease, or whatever, and you then cut it off, it's a brown.

Hay is a green (N) material, while straw is a brown (C) material.

Karen

Ok, that's makes some sense. So if I prune a tree and it's during the growing season, it's considered a green...right? If I rake up the leaves in the fall they're a brown. Okay so far? Now, how about the branches that will be chipped and/or shredded? Do we follow the same logic? Green when growing and brown when dormant? Or, (I know you should never start a sentence with a preposition) is the "wood" always considered a brown?

jkochan: Hmmm........ I was referring of grass specifically . Dead dry wood has a very high C:N ratio, as high as 500 or 600, but I'm not sure about fresh wood cut from a healthy tree. It would be lower it seems but I don't know how much lower. Anybody know? Or you could google it, look through some online charts of C:N ratios if it's important to you.

Never been an issue for me because I compost little wood or wood products. and I honestly worry little about stuff I toss in there.

Karen

I'm not an expert on C:N ratios or the structural makeup of plants but the general rule of thumb that I use for my compost bins is if it's hard or "woody" it's likely that it will be a "brown" or have a high carbon content. Conversely if its soft, moist and "Green" it's likely to have a high Nitrogen content.

That would only apply to plants, and as Karen states above, I lookup the C:N ratio if it's a point of interest.

Having stated all that, I do know that wood products don't break down very easily. They are considered a brown and take considerable amounts of Nitrogen to break down, and if used in a compost bin should really be chipped down as much as possible. Sawdust would be preferred.

I will place relatively fresh Chicken manure in my compost bins that may be mixed with sawdust (old bedding). If you look at the Nitrogen content of Chicken manure you will see that it is very high.

When it's "ready" I will still see some of the sawdust in the "finished" compost. This is ok in small amounts. Large amounts that are not completely broke down will essentially rob the Nitrogen out of the soil because its still breaking down and needs the Nitrogen to complete the process of decomposition.

This is the reason that I don't like to use sawdust too much for our Chicken coop bedding. I know that it's going into the compost bin and generally prefer to use straw for bedding material. It's not quite as woody and breaks down much faster.