If it is really well composted you can probably use it fairly liberally. Just don't be too liberal with it where you want to grow root crops. It will cause hairy roots.

I'm sure you could add it to the compost pile. It all just depends on what you would like to do with it and the size of your garden.

George
Tahlequah, OK

Maybe its where I live but horse manure is pretty free around here especially during the spring and summer months. If the manure has been composted then it shouldn't be a problem to mix with the soil your adding for flower beds. And like George said adding it to your compost pile should be fine.

I agree with that the others said, but you need to be aware that certain herbicides that break down too slowly have been known to survive the horses' (and also cows') intestinal tracts and these residues can remain at high enough levels to contaminate your soil for several years.

While the issue with these persistent herbicide residues has existed since around 2000, only recently was it learned that these herbicides were showing up in bagged, name-brand horse feed. The herbicide residues were in the horse manure of animals fed that feed at such a high level that people who purchased compost that contained the residue had damage (including plant death) to their gardens. Once your soil is contaminated with these residues it can kill all or most non-grassy plants you attempt to grow in that soil for several years.

For a long time, though aware of this issue virtually since the first year it happened, I thought of it as something that happened someplace else to someone else, and not to me and the people I know. Then, a couple of years ago, one of our neighbors told me she thought she had inadvertently contaminated her vegetable garden with these herbicides and that she was going to have to make a new garden plot somewhere else on the property. She didn't mention if she had accidentally introduced the herbicide residues into the garden via contaminated horse manure, stable bedding, hay (most horse people here where we live do spray this class of herbicides on their hay pastures to keep them free of broadleaf weeds) used as mulch, or what....but it didn't really matter. Regardless how it occurred, it ruined her ability to use a garden space she had used for years and years and she was very upset about that.

So, always be careful when you "import" horse manure or cow manure to use in your growing beds. Even people who do not spray their hay pastures with these herbicides could unknowingly feed their horses bagged feed that is contaminated.

I'm linking one of the more recent articles on this subject because it is the one where I first read about the discovery that the herbicide residues were being found in horse feed. The description of how the killer compost was traced back to bagged horse feed is in the section of the article called "The Plot Thickens".

Dawn

Here is a link that might be useful: Killer Compost and the link to Horse Manure