For what it's worth i was brought up on a farm, had most animals at some stage or another, and have grown veg all my life , and my opinion on "dung" is ;- all of it should really be left in a compost heap for a year to get the best benefit from it ,most bird manure is pretty high in nitrogen, and tends to make things above the ground grow ,leaves etc, horse,cow,sheep,goat etc great stuff,when about a year old and dug into the ground over a few years the fertility will soar, pig manure is pretty "cold" manure but high in iron minerals and also good for the ground in the longer term,
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