- Agronomic: potatoes, hay
- Animals: poultry
- Animal Production: manure management, stocking rate, feed/forage
- Crop Production: crop rotation, cover crops, nutrient cycling, organic fertilizers
- Education and Training: on-farm/ranch research
- Production Systems: holistic management, organic agriculture, integrated crop and livestock systems
- Soil Management: soil analysis, nutrient mineralization, soil microbiology
I work on our family farm in northern Michigan. We raise mostly tree fruit, cherries and apples, but also grow specialty potatoes. I raise some poultry, and have rented some acres which I raise field crops on- mostly small grains.
Sustainable practices carried out before the grant: cover cropping, compost usage- though I had only been farming on my own for a year or so before getting this grant.
PROJECT DESCRIPTION AND RESULTS
Goals: To try and determine the soil building potential of having poultry raised on temporary pasture.
There were five test plots- two areas with chickens pastured, two controls, and one area where chicken litter was applied at about 10 ton/acre (plot 3)- a newly planted asparagus patch.
One batch of chickens was pastured in plot 1, followed by vegetables. Two batches of chickens were pastured in plot 2, followed by vegetables. The controls both had vegetables grown when vegetables were grown in the plots.
• Dr. Rob Sirrine, Extension- consultation with grant writing, evaluation of results
• Dr. Nikki Rothwell- consultation with grant writing, evaluation of results
• Joe Scrimger, Organic Crop Consultant- advice, evaluation of results
• Dr. George Bird- nemetologist, advice, evaluation of results
Basically, we found that there is a positive effect on the soil- there are more nutrients and soil microorganisms following the chickens. We did three types of soil tests- standard field tests (MSU) including NO3 and Organic matter, biological tests (solubility method, Bio-systems), and nematode full-community tests. These tests were all useful in tracking the nutrient and soil biota changes, although the changes were somewhat slight. There were measurably more nutrients after the two batches versus just having one, but both were somewhat mild, and neither were anywhere near a polluting level. The area where we spread 10 ton/acre chicken litter showed definite increases in nitrogen and other nutrients.
The results were basically as suspected, although the nutrient addition from having the poultry pastured for six weeks, at about 13 or so square feet per bird average, was a bit less than I had expected. The vegetables (mostly potatoes) did not show a large difference following the one batch, but did following the two-batches of chicken. Below are comments from Dr. George Bird:
Dr. George Bird Comments
As indicated in Table 1., I have designed the reporting format to include four management systems. It is my opinion that the asparagus/chicken manure plot and 2007 data should be considered separately.
The 2007 clover/grass cover crop plus poultry resulted in a total of 1128 nematodes/mycorrhizae spores/oligocheates per 100 cc soil on June 19, 2008, compared to a mean of 691 (563-759 range) for the other three management systems (Table 1.). The same response was observed on June 19, 2009, following the inclusion of poultry in 2008 (818, compared to 469). This is a strong indication that the inclusion of the poultry resulted in a significant increase in organic matter available for nutrient mineralization. It appears however, that the 2008 vegetable crop following the poultry in 2007 depleted this increase in soil resources available for biological activity. In general, the nematode community structure analysis, without the mycorrhizae and oligocheate data, was appropriate for monitoring the changes in soil biology associated with the four management systems (Tables 2 & 3).
When the research was initiated in 2007, the site had a moderately high population density of bacterivores (Table 2). The population density was significantly lower at the beginning of 2007, except were poultry was included or poultry manure was used in the asparagus system. In general, the soil biology was low to moderate and requires at least an additional four years of soil quality enhancement to reach an optimal dynamic equilibrium for an organic system
Here are some of Joe Scrimger’s comments:
We are going to try to put all the tests on a spread sheet to look for patterns, in general what you are saying in overview is good, but you need to track some with George's nematode test that suggests that you are bacterial dominated and our Bio-test also tends to say the same, in respect to phosphate release. In 2009 you showed more phosphate solubility on the 6/24/09 Bio-test in plots 2 & 3, which suggest more fungal organisms. Plot 3 also showed a too high of a nitrogen level for potatoes, which would lead to more potential scab. In a Biological System a beneficial fungal dominated system is needed to show fungal disease resistance, while keeping the nitrate and the beneficial bacterial side of the systems balanced, lower than needed for corn, if producing potatoes. Plot 2 showed the most potential for potatoes, but it was not balanced but rather approaching balance, needed more energy, less potash solubility and a little more phosphate solubility. More poultry manure by nature is going to push more nitrate, phosphate and potash and will be bacterial dominated. Which will not give good disease control in potatoes, but applied to poor testing soil would work for corn.
I will attach the Spreadsheet Dr. Bird sent to me, and I can provide copies of the soil tests upon anyone’s request. (phone: 231-371-3444)
Part of the findings of this study relate to my ability to determine how many birds over time I can have without causing nutrient overload or N leaching. I believe that in a Salatin- style setup, using chicken tractors, chickens could be passed over the same area 5 or more times per year (for short amounts of time) and help build the soil for a couple/ few years- however it would be good to see a test specifically of that type of system. In a more permanent or semi-permanent system (which I am moving towards,) it is probably possible to have two batches per year for several years without having a nutrient buildup problem. Having a cover crop after the second batch would help keep the soil healthy. This has affected my farming enterprise by helping me decide how many birds I can raise for the area that I have, using our semi-permanent methods.
The other part of what I learned is something about the benefits to the soil of having the poultry raised on it. First, it increases the microorganisms. Second, there is an added nutrient value, however, I think that the chickens would need to be pastured frequently and for a couple of years to do significant soil building. That said it does seem to be a valuable tool for soil building in conjunction with poultry rearing, and I think that the best way it can be used is to rotate between vegetable cropping- possibly one or two years (or three) of chickens, then back into vegetable production. This method has great potential for farmers who don’t have a lot of land, and are both market gardening and raising poultry. It should also be great for very intensive operations such as urban farming.
I spoke twice at the Michigan Organic Food and Farming Conferences (once in 2008 and once in 2009) about the project and expected results. I spoke about the project several times at the Northwest Michigan Horticultural Station in different meetings, and in different contexts. I had a field day at our farm which had light attendance but there were a couple people there. I sent a press release for the field day to the NW Horticultural Station, to the participators in the project, MSU Extension (Leelanau County,) and two Michigan organic listserves.
I plan to send to write up a small summary and send it to the NCAT specialist on livestock, and the NCAT specialist on poultry, and to a group of producers in northern Michigan who are involved in small scale poultry enterprises called the ‘Chicken Coupe.’
No recommendations, other than to continue the program.