Soils and Systems Fact Sheets:
Ask an Organic Specialist: Soils Answers
Feed and bedding: Arsenic is the only prohibited feed input that could have been fed to non-organic animals, which would prohibit use of manure on organic land. Arsenic has at times been added to conventional broiler chicken feed. It is an element, and will remain in your soil since it does not break down. You must document that this is not in the feed if you are using broiler manure. Other than this, animals could have been fed genetically engineered (GE) feed, or given antibiotics or hormones, and the manure is still allowed on organic land.
However, if the manure includes bedding, it cannot contain prohibited synthetics, like treated wood shavings or glues/paints/heavy metal-based inks. On the other hand, GE corn stalks, or any conventionally raised crop is allowed as bedding in manure that can then be spread on organic land.
Piles and Lagoons: You must obtain a document from the manure supplier that a manure pile or manure lagoon did not have prohibited synthetic items used in or on the manure. For example, no non-approved fly sprays or herbicides may be used on manure piles, or non-approved synthetics put in manure lagoons to control odor. A natural lactobacillus bacterium is allowed as a manure lagoon additive, as long as it does not contain non-approved synthetics. Manure that has been piled outside or in a barn for 10 years with no turning and/or no documentation that it reached the high temperatures required for compost (see below) is still considered raw manure, and can only be used according to the manure restrictions on human consumed crops.
Human-consumed crops: If you are growing crops for human consumption, and the manure is not composted or processed, the manure must be incorporated either 120 days before harvest of the crops where the crop has contact with soil (either growing in or on the ground, or where rain might splash soil on the crop, such as beets, tomatoes, peppers), or wait 90 days before harvest where the crop does not have contact with soil (i.e. corn or soybean seed).
Compost and processed manure: Manure that has been composted (documented temperature of over 131 degrees for 15 days and turned 5 times) or processed (150-165 degrees for one hour and tested to have less than 1000 most probable number (MPN) of fecal coliform and 3 MPN salmonella per 4 gram sample) can be used up until day of harvest with no restriction. If you are composting only vegetative matter, without any animal by-products, then there is no requirement to track the compost reaching a specific temperature. Non-animal product compost can be spread this on your organic crops at any time.
Using manure: Be aware that raw manure that has not reached the high temperatures of composting or processing will contain viable weed seeds. You will be adding more, and possibly different, weed seeds to your fields. It is a good idea to obtain an analysis of the manure you are using so you can better manage for the nutrients it provides.
Compost that might contain manure must meet the composition, temperature and turning specifications in the National Organic Standards:
(i) Established an initial C:N ratio of between 25:1 and 40:1; and
(ii) Maintained a temperature of between 131 °F and 170 °F for 3 days using an in-vessel or static aerated pile system; or
(iii) Maintained a temperature of between 131 °F and 170 °F for 15 days using a windrow composting system, during which period, the materials must be turned a minimum of 5 times.
The county/city must provide the documentation to show these standards were met before you can use a material as compost. If they cannot prove they have met these standards, it may be possible to still use it, but it will not be considered compost, it will be considered raw manure, and will have different handling requirements:
1) Raw animal manure, which must be composted unless it is:
(i) Applied to land used for a crop not intended for human consumption;
(ii) Incorporated into the soil not less than 120 days prior to the harvest of a product whose edible portion has direct contact with the soil surface or soil particles; or
(iii) Incorporated into the soil not less than 90 days prior to the harvest of a product whose edible portion does not have direct contact with the soil surface or soil particles;
Composted and un-composted plant materials without manure have no application restrictions, but the composting center must verify that the compost contains only 100% plant materials. If there is a possibility that it contains pet waste (animal manure) then it must be handled as raw manure.
Whether or not it contains animal manure, you still must make sure compost contains no prohibited materials:
•Recycled building materials/lumber (due to paints, varnishes and glues)
•Plastics and other un-compostable synthetics
Check with the composting facility to see if they have the necessary documentation. If other organic farmers have been using their product, it is quite likely they have this paperwork on hand. Also check with your certification agency, which can do a product review if it has not already reviewed this compost for other farmers. Ultimately, your certifier makes the final call on whether a product is allowed or not. All new inputs should always be verified and added to your crop input list before use.
Resources & Research:
Organic soil samples needed
The National Soil Project is comparing soils on organic farms with those on conventional farms to see which sequesters more carbon. Researchers need more soil samples from organic farms. In return, farmers will receive free analysis of their soil’s total and sequestered organic matter content. Learn more and download the sample submission form.
Easily compare 58 crop species with a new cover crop chart from the Northern Great Plains Research Laboratory. The 67-page document includes the chart showing growth cycles, plant architecture, and relative water use, plus additional details for each species such as seeding depth, pollination characteristics, and forage quality. Primary sources of information include the Midwest Cover Crops Council, USDA-SARE, and USDA-NRCS PLANTS Database. For recommendations on choosing cover crops based on the desired outcomes, see the “How to Choose Cover Crops” MOSES factsheet available at the top of this page.
A team of cover crop experts from the Midwest Cover Crop Council has created a web-based system of Cover Crop Decision Tools to help farmers select the best cover crops for their area. The online tools walk farmers through the process of choosing their region, soil drainage class and goals such as finding soil builders, nitrogen sources, weed fighters and forage harvest values. The tools deliver recommendations of various cover crop species and their optimal planting date windows based on 30-year average frost dates in the user’s county.
The USDA-NRCS has a new series of short videos highlighting ways to improve soil health while benefiting the environment and lowering production costs. The series includes interviews with some of the nation’s leading experts in soil biology, agronomy, entomology, and soil ecology.
A guide to the Conservation Stewardship Program from National Sustainable Agriculture Coalition (NSAC). It is available for download at their website.
This checklist from the Natural Resources Conservation Service (NRCS) can help farmers increase crop production and profitability by managing for soil health. The 2-page PDF shows the benefits of various types of soil health management systems and covers the four basic principles for improving soil health:
1. Keep the soil covered as much as possible.
2. Disturb the soil as little as possible.
3. Keep plants growing throughout the year to feed the soil.
4. Diversify as much as possible using crop rotation and cover crops.
A long-term southern Wisconsin cropping systems study shows that soils under managed grazing have a number of positive characteristics compared to soils under other cropping systems. The Wisconsin Integrated Cropping Systems Trial (WICST) provided data on three cash grain cropping systems and three forage systems. The study found some interesting differences between the systems in terms of erosion potential, earthworm counts, water stable aggregates, soil carbon, and the Soil Quality Index.
The pocket-sized guide from Purdue University and the Midwest Cover Crops Council is designed to help farmers choose, grow and use appropriate cover crops in their farming operations. The updated edition features seven new topics, including suggested cover crops for common rotations, seeding rates, and research on cover crops’ impacts on cash crop yields. The 166-page resource is $5.
The National Wildlife Federation has released a report from a June 2012 meeting that brought together 36 of the leading experts in cover crops in the Midwest and Great Plains. These farmers, scientists, extension specialists, and policy experts met for two days to discuss what they saw as the biggest barriers to expanded cover crop adoption. The “Roadmap” they developed for addressing these barriers is the first step toward achieving the goal of 100 million acres of cover crops by 2025.
Provides soil data and information produced by the National Cooperative Soil Survey. It is operated by the USDA Natural Resources Conservation Service (NRCS) and provides access to the largest natural resource information system in the world. NRCS has soil maps and data available online for more than 95 percent of the nation’s counties and anticipates having 100 percent in the near future. The site is updated and maintained online as the single authoritative source of soil survey information.
The Natural Resources Conservation Service (NRCS) offers a series of fact sheets on soil management.
USDA Risk Management Agency has created a two-page fact sheet explaining allowable deadlines for termination of cover crops to qualify the subsequent crop in the field for crop insurance.
- Current and Future Prospects For Biodegradable Plastic Mulch in Certified Organic Production Systems
Extension experts from Washington State University, the University of Tennessee and Texas Tech explain how biodegradable plastic mulches are made; how biodegradability is measured; current techniques on evaluating biodegradable mulches; and research and policy progress to date. The purpose is to inform agricultural professionals, farmers, and policy makers about the suitability of biodegradable plastic mulches for use in certified organic agriculture.In October 2012, the National Organic Standards Board recommended that biodegradable mulch be added to the National Organic Program’s list of approved substances. NOP has stated it is working to include this on the approved synthetic list for crops, sometime in the next year. The NOSB recommendation is:
(iii) Biodegradable biobased mulch films to be reviewed meet the following criteria:
(A) Completely biodegradable as shown by:
- meeting the requirements of ASTM Standard D6400 or D6868 specifications, or of other international standard specifications with essentially identical criteria, i.e. EN 13432, EN 14995, ISO 17088; and
- Showing at least 90% biodegradation in soil absolute or relative to microcrystalline cellulose in less than two years, in soil, tested according to ISO 17556 or ASTM 5988;
(B) Must be biobased with content determined using the ASTM D6866 method;
(C) Must be produced without organisms or feedstock derived from excluded methods; and
(D) Grower must take appropriate actions to ensure complete degradation.
Biobased: organic material in which carbon is derived from a renewable resource via biologicalprocesses. Biobased materials include all plant and animal mass derived from carbon dioxide recently fixed via photosynthesis, per definition of a renewable resource (ASTM).
From the Organic Broadcaster:
Multiyear crop rotations are a central tenet of organic crop production, and for good reason. Read more.
The idea that nutrients are depleted from soil when crops are harvested is not correct. Nutrients are removed when plants are harvested, but this doesn’t mean the soil has no nutrients left. Read more.
Marvin Lynch, an organic dairy farmer from Cascade, Iowa, hosted a field day July 15, to share how he transitioned CRP (Conservation Reserve Program) land into organic production. Read more.
High tunnels allow vegetable farmers to extend the growing season, but often require supplemental heat to protect plants during spring and fall cold spikes. Read more.
The potential benefits of using cover crops are wide ranging and well documented. The potential benefits of using cover crop mixtures, however, have been less thoroughly explored. Read more.
Rotary hoeing and in-row cultivation during the grain growing season help suppress weed populations. Read more.
With the changing climate delivering hotter, drier summers, many farmers are seeking solutions by irrigating crops. Read more.
By observing the weeds growing in your fields you can better understand your soil’s ecosystem and nutrient profile. Read more.
Converting Conservation Reserve Program (CRP) land to organic production looks attractive: the land is already certifiable…. Read more.
Over the past decade, radishes have been redefined; once known almost exclusively as a pungent vegetable, radishes…. Read more.
Food safety, as we’ve learned to talk about it in the wake of troubles like the 2006 E. coli 0157:H7 outbreak from spinach…. Read more.
New Tool for Organic Growers: PuraMaize Blocks GMO Contamination
One of the challenges organic farmers face is the potential of organic crop contamination…. Read more.