As a rule manures, with a Carbon to Nitrogen ratio of about 20:1, are a Nitrogen source or a green. You do not need, or want, 20 times more leaves (a misinterpretation of what is written) but you can mix 3 times more leaves then manure and get a good mixture.
You want a Carbon to Nitrogen ratio of about 30 parts Carbon to 1 part Nitrogen and in practice that works out to around 3 parts vegetative waste to 1 part manure.

Hay has a C:N of about 400:1. Seeing as its all contaminated with manure and urine, lets say its about 350:1.

You can do the math from there.

(350/30 to figure out how much N you need per volume)

I have never seen hay listed as having that kind of a C:N ratio, 35:1, some places 25:1, is more likely. Manures are listed as having a C:N ratio of 15:1, so what you have is a "green".

If the bedding was shavings (as in wood) or straw (I've never seen anyone use hay as a bedding or any hay with C:N of 400:1) and there wasn't copious amounts of it, then the C:N probably doesn't need any adjustment.

I'd still consider adding leaves for the nutrients but I wouldn't go too far out of my way to add some.

Lloyd

I meant wood shavings (which is usually put in horse bedding), has a C:N of 400:1.

Here's the math i came up with:

Idea is a 30:1 Carbon/Nitrogen ratio (Browns:Greens)

Determine the C:N ratio of the Browns and Greens you will be adding. There are many charts online that give the C:N ratio of commonly composted items.

Browns Greens
C1:N1 C2:N2

Divide the C by 30 for Browns and multiple N by 30 for Greens

N1 = C1/30 C2 = N2*30

Divide those 2 numbers

NUMBER = C2/N1

Multiply C by the number for Browns and divide the N by the number for Greens

High Carbon High Nitrogen
C1*NUMBER N2/NUMBER

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Example:

Wood Chips Urea
400:1 1:46

N needed to make a 30:1 ratio for Wood Chips(N1)
= 400/30
13.3

C needed to make a 30:1 ratio for Urea(C2)
= 46*30
1380

NUMBER = C2/N1
NUMBER = 1380/13.3
NUMBER = 103.8

C1*NUMBER
400/103.8 = 3.9

3.9 lbs of Wood chips to 1 lb or Urea will balance out the 400:1(Wood Chips/Browns) and 1:46(Urea/Greens) to 30:1
-or-
.26 lbs of Urea to every 1 lb of Wood chips. (1 divided by 3.9)

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The problem with calculations is everything (including the magic 30:1 ratio) is based on dry weight, and none of the stuff is dry, nor can you weigh it easily anyway. So managing the pile is a combination of guesswork and experience.

It's impossible to tell whether the horse stall cleanings are balanced or not because we don't know the ratio of manure and urine to wood or straw. A fast practical way to gauge it is to pile it up and let it rot for a few days. If it doesn't heat up, it's low in N. I suspect it will, at least somewhat, which means it's probably going to compost OK. If it gets very hot, it's on the high end of
OK for N content. If it gets very hot and smells like ammonia and other noxious aromas, too much N, so mix in some dry leaves, straw, shredded paper, sawdust etc.

PS: Hay and straw are not the same thing. I thought everyone knew this but I had to explain it to my wife just the other day, and she's an experienced gardener. :-D

When figuring ratios, is it by weight or volume?

Kevin

Dammit!

I forgot to read toxcrsadr's post ---LOL

Never mind.