Fertilizing with Manure

[offgridbrandon]

I am new to organic gardening, but excited about the change. A neighbor is willing to ‘share’ manure from his chicken coop and goats. The chicken manure is mixed in with straw from the coop and has been composting for a year. Are their any health concerns about using manure for fertilizer? How long should it be composted before being used in the garden? 😮 and for the question I am most embarrassed to ask, does one type of manure need to compost longer than the other?

Any responses would be appreciated!

[Crabapple Farm]

Yes, pathogen contamination can be a concern with using manure for vegetable crops. It is more of an issue with crops like spinach or lettuce than, say, eggplant, which washes clean and you cook before eating.
Proper composting will kill pathogens, but “aging” alone might not. My basic rule is, if it seems like there’s still shit in there, don’t put in on your food. It should look, feel, and smell like compost, not manure. Feel is important – if you aren’t willing to handle it with your bare hands, it ain’t ready.
The Federal Organic Standards (we’re Certified so I’m up on them) require waiting 120 days after incorporating manure in the soil before harvesting a crop, or 90 days if the harvested portion is not in contact with the ground (such as sweet corn, well mulched tomatoes, etc.). That time period should be sufficient to allow soil-dwelling microbes to kill off any pathogens present in the manure. (that’s for manure, not compost)
Of course, if the source is animals that you trust are healthy, and you trust your immune system, don’t worry about. We sell vegetables to the general public, so are careful, but tend to eat a fair amount of manure ourselves over the course of an average week inadvertently (tail in the face when milking, hitching, etc. breathing dust in the chicken house, and so forth) Not Much, but enough to feel like our immune system at this point can handle a little bit of whatever our animals have. Especially since we aren’t real concerned about our animals carrying any serious pathogens.
-Tevis

[JBurch]

Does a person have to be careful where he get his manure? For example I don’t have enough animals at present to produce enough ‘clean’ manure to satisfy my need for fertilizer. If I were to go to one of my neighbors who has an excess of manure do I need to worrry about residual antibiotics, growth hormones and other pharmaceuticals in the manure and then contaminating my crops? This has been on my mind for years but recently even more a concern because of news reports of waste treatment plants in big cities having difficulting removing pharmaceuticals from the waste they were treating.

[jen judkins]

I too am concerned about residual toxins and antibiotics. I rarely use traditional wormers on my horses, but rely heavily on ‘manure management’. If I do chemically worm, I separate that manure and send it to my burn pile in stead of the compost bin for a few days. Its not very scientific, but ‘feels’ right to me. I use manure as compost all over the farm and want it to be as clean as possible. Parasites are an issue. I do fecals on my horses very regularly to be sure their parasite load stays low. I’ve been lucky…probably because the land I came to was never stocked with animals, so I’m not dealing with decades of questionable pasture management.

That said, I’ve of the mind that we shouldn’t keep our environment too clean…I think it is healthy to be exposed to plenty of microbes. I’ve always found it interesting that my dogs (we have 6) who eat horse manure fresh off a steaming pile all day, never have worms on their fecals each year…I’ve actually never had to worm them.

If you are getting manure from a boarding facility that does worming every 6-8 weeks, you might want to pass.

jennifer.

[Gulo]

Then there are weed-seeds that can be spread in manure, another reason for composting – kills the seeds.

Then there are pesticides. Quite a few people around here cut “ditch hay” – they mow the grass on the road allowances for ‘free’ hay. It’s a great idea, except for one thing. The county sprays the verges with something called “Tordon” to control thistles and such. Tordon has as much as a five year residual effect. They say it won’t hurt your livestock (of course they say that, it never does “hurt” anything when you ask, does it?), but what it will do is kill your crops if you use manure from animals that have eaten this ditch hay. So i wouldn’t want manure from people feeding ditch hay.

All this is another reason for a biodynamic model where your inputs all come from the farm itself.

If you do your own composting, remember to cover the manure, either with tarps or under sheds so that weather doesn’t leach out the nutrients. Ours goes six months to a year at which time it smells like nice fresh humus.

[JBurch]

This makes me feel somewhat better about keeping my hay burning horses around. My son and I hauled up a load horse manure (regrettable with a GMC PU- not DAP) from the location we have been feeding our horses. As far as I know this is the only ‘clean’ manure around since we rarely medicate our horses and up till this year we know the hay has been chemical free. I would bet the prairie hay I bought this year is chemical free too since it has weeds in it.

Now I just need to get busy teaching some of the hay burners to drive.

I did not know I needed to cover my compost pile to preserve nutrients. Thanks, Gulo.

[Author]

Posts