Soil Fertility

 Soil Fertility

This page is under development–Stay tuned! (Contact hestrin@uvm.edu if you would like to contribute!)

Treated or raw, animal manure is the most common NPK fertilizer used on Vermont produce farms. Manure is an excellent source of time-released nutrients, and it helps to build organic-rich topsoil. But manure is also significant food safety risk and should therefore be managed carefully. Click here for a general fact sheet about manure management and composting.

To mitigate food safety risk, most Vermont produce growers follow the NOFA guidelines for manure management : waiting (between application and harvest) 90 days for plants with above-ground edible portions (e.g. corn, apples) and 120 days for plants with edible portion in contact with soil(e.g. lettuce, carrots). These waiting periods are based on common practice and practical experience and not on rigorous field research.

The FDA has recently stated that they will not “take exception to the NOFA standards, and that in the meantime, they intend to conduct a risk assessment and extensive research to strengthen scientific support for any future proposal, working with the U.S. Department of Agriculture and other stakeholders

VVBGA Fieldnotes:

Always record date and location of manure and store records securely

For the visually inclined, record spreading  and planting dates on a farm map, updated annually.

When making wind rows or piles for composting manure, position them on the down hill side of crop fields, makes sure they have adequate vegetation buffer and/ or, plant corn.

Planting a tall heavy feeder like corn adjacent to this wind row, may help absorb nitrogen and reduce risk of contaminated run off.

Is there enough buffer around this manure pile. Best Practice is to observe runoff patters during the heaviest rain events!