Collecting wet (fresh) or dry (aged) manure is a matter of personal preference and either way will work for the compost pile. Manure should be composted before being added to the soil. If you are lucky enough to have a choice of manures, try different aging levels and see what works best for you.
Fresh, Wet Manure
Fresh, wet manure has a higher moisture and nutrient content, but can be more than a bit odorous. If you collect the proceeds of mucking out a stable, manure will already be mixed with straw or sawdust or other organic carbon which will help to balance the nitrogen and moisture. Throw it all in the pile. The better the carbons are mixed in with the manure, the less the stink. You will add more carbons while building your pile, but probably little or no need to add water.
If the manure has been left in the pasture where it dropped, with no protection from the elements, rain will leach nutrients into the soil over time. Unless the manure is extremely old, it will still contain nutrients after it has aged. If it is ancient, it may be low on nutrients but is still good to add to your pile or directly to the soil because it will improve the soil structure.
Aged, Dry Manure
Much of my childhood years were spent on my grandparents’ farm. We would somersault down hills, perform cartwheels across fields of hay and race each other to the far side of the pasture. Thus, my earliest encounters with cow and horse manure were accidental so, naturally, I developed a strong preference for dry.
The best thing about dry is that it doesn’t stick. It is less heavy than wet, making transporting and shoveling it a lot easier. Last but not least, a lot of the stink has gone out of it. It can get so dry and aged that you can just crumble it up into bits – while wearing gloves.
But manure can get too dry to decompose easily in a pile, so be sure to add plenty of water after every 4” layer is added. Organic materials should be about as wet as a wrung-out sponge. When working with a high proportion of manure in the pile you may just want to “guess-timate” moisture levels rather than test by squeezing.
On the negative side of dry manure, you have to deal with the “dust.” It’s best not to work the pile on a windy day. You can use dust masks sold in home improvement stores.
Dry manure has probably been out in weather elements while it aged, so a portion of the original nutrients have leached out in the rain. But it is still very beneficial to your pile and the finished compost will be good for your soil.
Theoretically, if you stored fresh manure out of weather elements while it dried, it would retain more nutrients. I can’t quite picture how the average person would do this in a practical way, so if you have any ideas, let me know.
Mary Tynes, Master Composter, www.mastercomposter.com
Image Credit: http://www.flickr.com/photos/tedpercival/2115091668/