"I'm confused."

A lot of people are, including some of the frequent contributors to this forum so don't feel bad.

From what I can gather, because 30:1 is the 'optimum' ration of C:N for composting it sort of became a 'dividing' line. So if a material has a C:N ratio of, lets use 20:1, it is 'deemed' to be a green/nitrogen source. If another material has a C:N of 40:1, it is 'deemed' to be a brown/carbon source. The color of the material itself has nothing to do with the classification. I had one person ask me if a banana peel is yellow, is it a green or a brown. Taken out of the context of composting, it was really quite funny. Their daughter looked at us like we were nuts! Which, in her defense, I suppose had some a lot of merit.

How those ratios for the materials is determined, I have no clue but suspect it involves witchcraft and sorcery. And even if a material is given a ratio, it should be taken as more of a guideline. The ratio can, and will, vary for any number of reasons.

There are numerous tutorials online that explain it better than I ever could. Here is our local one. It even has some french stuff way down at the bottom of the link.

Warning though, composting can be addictive and people will look at you as if you are deranged, once again, not wholly without merit I suppose.

Good luck and have fun.

Lloyd

The best approach is to look at lists of "greens" and "browns." We have a list in the FAQs, but lists are all over the internet.

Your manure, though, is high in nitrogen and is, therefore, a "green".

(I don't care if something is a green or a brown; either way it's going in my compost pile.)

Starbucks sometimes puts a fine print label on their coffee grounds which are definitely brown in color. The label identifies them as "green" for composting. I find it very sad that someone stooped to creating this brown/green jargon to sell and article or a book. C and N worked so well.

I see green and brown used here and don't know what materials constitute them.

Your confusion is common if that is any comfort. ;) The green/brown labels are an artificial construct created eons ago by someone as a supposedly useful way of separating nitrogen sources from carbon sources for composting. Nitrogen=green and carbon=brown and those labels are far more accurate and better labels to use but old habits are hard to break.

As already pointed out, it has nothing to do with the color of the component and this is explained in detail on most knowledgeable sites about composting and in the FAQs here to a degree. Those FAQs are not perfect but still quite helpful to you so I strongly suggest a review of them.

Once you get clear on carbon vs. nitrogen then many tables are available on what the carbon/nitrogen ratio of any particular component is. Cornell University site (linked below) is highly reputable and their C/N ratios are not the result of witchcraft as suggested but scientific analysis of the material.

Common Materials

Carbon to Nitrogen Ratios

High Nitrogen Materials:
Grass Clippings C/N 19:1
Sewage Sludge (digested) 16:1
Food Wastes 15:1
Cow Manure 20:1
Horse Manure 25:1

High Carbon Materials:
Leaves and Foliage 40-80:1
Bark 100-130:1
Paper 170:1
Wood and Sawdust 300-700:1

See the differences?

Using their recommended effective composting break point of 30:1, one can easily determine which side of the line, carbon (brown) or nitrogen (green) any item falls.

That said, please do not fall into the trap of fixating about which it is - green or brown - just compost it. ;)

Dave

Here is a link that might be useful: Cornell Composting

Here is a link to the Composting FAQ's here.

Here is a link that might be useful: Composting FAQ

Gee, no WHITE stuff?

Thanks for the responses. I knew it didn't have to do with color but with some mysterious component of the material. Thanks for de-mystifying it for me. I really appreciate the detailed replies.

As for no white...apparently you can get some really large WHITE grubs called Green Fruit Beetle. They are actually good guys and provide the missing "white." LOL

Good answer janegael.
We won't discuss or even mention the "other" white stuff.

the "other" white stuff. You mean turkey right, otis? ;)

I added some old pumpernickle turkey to one pile earlier today but it was brown so ok.

Dave

I use 100% rye br..d which is close to Pumpernickel so I throw that in also. I have never seen it get so..y.

So yeah, we're doing Ok by the Compost Inspector.

While we are still near the subject, "green" is further confused by the environmentalists use of the word. There is a dictionary search tool called Onelook.com that finds "green" in 66 dictionaries and brown in only 47 dictionaries.

I have yet to find anyplace where lexicographers have put green and compost together. It seems to be clique jargon.

Being math challenged in the extreme my eyes glaze over at the numbers.

If 30:1 is optimum does that mean I would basically put down 30 cups of shredded leaves for every cup of horse manure? If so, to me this means that I need to put a LOT more carbon/brown onto my pile than I would green.

Some of the manure I will be getting will have hay/straw mixed in and some will have sawdust. It sounds as if, for me, it will be pure guesswork to figure out a ratio. I would think that as long as I don't burn my plants with fresh manure they should be ok with whatever I can get as long as I don't get too crazy with either the carbon or the nitrogen side of things.

Thanks a lot for the replies. I appreciate it.
Jane

You have to figure that HM, in and of itself, is close to 30:1 due to undigested hay, etc. That's why I don't put in more leaves than HM. Wood chips, sawdust, straw will increase ratio even more. If that's the case, I sprinkle cup of alfalfa meal, or dog food on each layer. After a while you will get the feel for right mixtures to get the heat.
thanks,

If 30:1 is optimum does that mean I would basically put down 30 cups of shredded leaves for every cup of horse manure? If so, to me this means that I need to put a LOT more carbon/brown onto my pile than I would green.

Yes, if you were going to actually measure it by the cup then technically you are right 30 cups of leaves for 1 cup of manure + 1/2 cup of kitchen scraps. ;)

But you honestly don't need to "do the math" or be nearly that technical for it to work fine. ;) Shoot for 3:1 - 3 parts carbon for 1 part nitrogen and you are in the ballpark for the most part. If it starts to smell bad or is too wet, add some more carbons.

An active, effective pile does contain more carbons than nitrogens - about 2-3 times as much.

And try for more diversity in components too - the more diverse, the easier the math. ;)

Dave

"If 30:1 is optimum does that mean I would basically put down 30 cups of shredded leaves for every cup of horse manure?

Uh, not really, no. The leaves have their ratio and the manure has its ratio.

I'm gonna guess that a 1:1 shredded leaves to pure HM by volume will get you close enough. If there is a little bedding in with the HM, less leaves (maybe none) are necessary. If there is bedding with a lot of urine in it, then more leaves may be necessary. If there is a lot of bedding in it, you might have to add N to get 'optimum'.

It may take a few attempts to get the amounts 'in the range', but if an offensive odor is detected, you can always add more leaves.

As glenam said, HM isn't far off of the optimum all by itself so not much in the way of a strong C is required.

Lloyd

Disclaimer: Never composted horse manure, I could be full of crap but composting is composting.

Somebody posted once that if you seal some 'greens' in a plastic bag in the fridge for a week they will stink when opened, while a batch of 'browns' treated the same way will not.

I find the terms useful -
Greens tend to be heavy, wet, fine-textured
Browns tend to be light, dry, coarse

Layering heavy/wet/dense with light/dry/coarse gives you an airy, damp pile that composts well. Too much 'greens' and the pile will likely stink and go anaerobic, too much browns and it won't heat up much and will break down more slowly.

I can't think of terms that do a more concise job than 'green' and 'brown' and figuring out which category the odd confusing ingredient, like coffee grounds and manure, falls into is a simple matter of checking a one-page, or less, list. C:N ratios are too complicated for the average composter to deal with, or want to.

I just throw everything (except whites surrounded by brown crust) in my compost bin. If it stinks/sticks together and slimy when being turned, I add more dry leaves and shredded newspaper/cardboard. I don't even shred the leaves, no lawnmower to shred them so I just throw them (red maple leaves) in whole. Any compost I get out of there is good enough for me. I don't grow veggies, no patience and too many slugs on my property. I lost the slug war.

Before following the post here on GW, I haven't done anything to my bin for the last 3 years. No turning, no harvesting. I didn't know that newspaper/cardboard when shredded could be added to the CP, and it is considered a brown. And I used to have too much green, so I stopped using the bin.
Last month I found out that the roots of my neighbour's trees snuck up into my compost bin and stole the nutrients out of my compost. There is a fig and pine tree growing near the fence.
I have that square black plastic compost bin with the door at the front that slides up to harvest.

Otis

This is more complicated that I'd hoped, but I was trying to get a feel for amounts. I don't think I want to sit around measuring horse poop by the cup. LOL

I'll just put down what appears to be relatively close and not worry too much.

Thanks for all the help. I really appreciate it.
Jane

Jane--My formula is to add what I have and mix it up. If it stinks, I add more high carbon (brown) matter and/or mix it more. If it doesn't get hot, I add more high nitrogen (green) matter and/or mix it up and/or add water.

I turn it every once in a while until I can't tell what's in it and it has cooled off for a week or so. Then I spread it on my lawn. If I used it on my garden, I might let it sit longer, but the garden mostly gets layers of leaves and coffee grounds in the fall.

Forget about C:N. Alternate 6" layers of horse manure with 6" layers of leaves. If the overall moisture seems like it will be dryer than a wrung-out sponge, sprinkle water over the layers as you go.

Then start reading up on C:N, nitrogen and carbon sources and all that, at your leisure, checking your pile every now and again over the next few months to a year to see how it's coming along.

My source for pure manure appears to have dried up, but I've found a closer source for manure. This, however, is mixed strongly with sawdust. I read up that sawdust will leach out the nitrogen of the manure and actually stunt plants unless supplemented with a strong nitrogen source.

I went to my local garden store and found that they had no idea what I was talking about and the only thing close to the Ohio State recommended level of 34-0-0 was chemical lawn fertilizer. I was talked into getting some blood meal, good but expensive and only 12-0-0. I decided to use it in a couple of small areas with the lasagna method but to go ahead and get the lawn fertilizer as I have over 60' of fence that I need to improve as the soil appears sterile. I intend to put Virginia creeper along the fence and hope it does get invasive as that would save me money. :)

I don't have any problem combining my love for organic gardening with the addition of some chemicals...if in the long run they benefit the soil and are not toxic.

It looks like my compost pile is going to get interesting and I've also decided to do some lasagna beds closer to the house for this year until I can get the compost cooked and find and afford the Virgina creeper.

Thanks for all your input. This thread is fascinating.

Here is a link that might be useful: Ohio State University Extension Fact Sheet

This is more complicated that I'd hoped

BINGO!

Simplify your life. Forget you EVER heard about greens and browns or carbon and nitrogen. Just start piling things up and they will always decompose.

I was posting this link on the sawdust thread when it occurred to me it also made good reading about the C:N ratio, with a helpful table on C:N and nitrogen content of common materials. Hope it helps!

Here is a link that might be useful: C:N ratio and nitrogen content