To get an inch of coverage you're going to need about 50 gallons.

9ft = 108 inches

9ft x 9ft x 1in = 108in x 108in x 1in = 11664inó (cubic inches)

11664inó = appx. 50 gallons.

....25 gallons for 1/2" cover...12.5 gallons for 1/4" cover...etc.

Something is better than nothing, though...even if you don't want to deal with 50 gallons. This calculation assumes an even spread...which is hard to do with manure applications below an inch because of it's natural clumping...so if you apply under 1" it may not totally cover the surface...just get close-enough-to-even distribution and don't worry about covering every little bit of space.

Wow; 50 gallons seems like a lot. If I put 25 gallons in this week and bury it as best I can, being lumpy and all. in the spring will it be easier to re-spread evenly?

Unless your area falls into some weird arctic freeze lasting all winter, by the time spring rolls around it should be broken down to the point where you can't tell the manure from the soil you added it to.

At that point any mixing/turning of the soil you do will incorporate whatever's around quite easily.

It doesn't have to be totally spread evenly...just avoid putting too much in one area and totally skipping other areas for best coverage application.

This post was edited by nc-crn on Tue, Oct 15, 13 at 21:13

How much manure you may need depends on what that soil needs and that can only be determined by having a good reliable soil test done.
What is the pH of that soil?
How much organic matter is in that soil?
What are the nutrient levels in the soil now?
Available nutrients in horse manure will vary depending on what they are fed but generally it can contain about 0.7 percent N, 0.3 percent P, and 0.7 percent K per ton.

kimmsr, If I had a 3 by 3 patch, would you still recommend a soil test?

Yes!

I had the soil tested last year and the PH was 6.8 and the soluble salt was 149. That's all the info they sent back.

So, taras, who did the test? Did you check the lab and what they did before submitting the sample? Did you ask the lab what they tested for?

Can I store the manure in sealed black garbage bags for the aging?

It needs oxygen to do it's thing...you'll have an extremely smelly mess that will probably gas off anaerobically enough to bust the bag if you seal it.

Piling manures to "age" is probably not a good thing to do since that manure can loose 25 to 50 percent of the Nitrogen and 5 to 25 percent of the Phosphorus and Potash. Much better is to compost the manure with 3 parts vegetative waste to every 1 part manure or, at this time of year, work it into the soil in the garden.

For myself, I am not so worried about 25 to 50 percent mineral nutrient loss. I still get some good nutrients, but perhaps even better is the organic matter from the rich hay and straw plus the manure.

I should have mentioned that I live in the Bronx and know as much about phosphorus and potash as I know about nuclear chemistry; I just want a better "farm" for my nine tomato plants. From what I've heard so far, the best advice would be to get the manure and turn it into my soil, cover it with mulched leaves and whatever grass clippings I have left to reduce the odor and flies. I was trying to avoid that procedure because turning the manure into the soil could get a little "messy". Again, I'm from the Bronx.

Taras, putting that manure down on the soil and covering it with the leaves and grass clippings, if 3 or 4 inches thick, would be as good as tilling the manure into the soil.

Problem solved! I can do that, Thank you kimmsr