ok lets fix this horse muck and any other manure question sorted once n for all .... whatever your adding its humus and fertiliserrs organic and chemical in 99% of places , horse muck isnt a patch on cow manure . firstly its dodo content is tonnes lower than cows ,its nitrogen content is massivley lower . but its bulk in fibre is higher . why simple because horses dodo apples in a stable usually on its own where cows are kept by the dozen in a byre or open barn and all they do is mill round tromping the dodo which is soggy sticky stuff into the straw they are bedded on . the cow manure is rich in nitrogen with all this chit tromping etc it cooks even in the barn having been put down at the beginning of winter and not touched other than to have more straw piled on top of the previos lot .
this is done on some farms once a week sometimes twice . then when spring comes the cows are let out to pasture and the now heavily manured bedding is dug out with a tractor mounted fork bucket and piled high the stuff cooks even more to the point where i have cooked eggs in it and seen it catchg fire .
Horse manure with load of shaving s flakes or chipped up medicated straw and its couple hundred apples gets piled high and it cooks but no where like its cow counterpart so ok use horse manure if that what you can get its fine to use if its not got masses of wood shavings in .if it has leave it one side and let it rot down for a couple years .i have a stable pile on the estate its been there 6 /7 yrs and its still got discenrable chips in it .i use it for tubs and hanging baskets because it holds water better .i also collect the apples from the pastures and pile them up . but you with horse manure only, add stuff to it chicken shed stuff even look for people with racing pigeons in your area ask for the dodo , any rabbit keepers can if they wish use the rabbit dodo straight away and its really the only dodo you can . but add it to the manure heap as an activator . now cover the lot with a thick black tarp or even a pond sheet to help cook it . these new green recycling places can turn this stuuff they collect into compost in 6 mths using activators and covering it so why cant you . incidently horse manuere does not burn plants anything like cow manure does when its applied .
hope this helps with making straw and chit into the best stuff ever for gardening all hail the * pile