Farmer-Led Trials Program Spotlight: O’Meara Family Farm
Interseeding Sunn Hemp for Soil Health and Hay Production
Written by Mary Hathaway, OFRF’s Research & Education Program Manager, and John O’Meara, FLT Program participant
This on-farm trial at O’Meara Family Farm will compare sunn hemp grown alone with sunn hemp interseeded with Japanese millet for hay production. Results from this study will help organic farmers determine whether interseeding can improve forage yield and quality while supporting soil health.
Source: O'Meara Family FarmCows grazing at O’Meara Family Farm.
O’Meara Family Farm is a certified organic livestock operation located in Northern Maine, near the Canadian border. Founded in 1999, the farm grows grain and raises grass-fed beef, pork, lamb, and geese. The farm comprises 160 acres, 110 of which are wooded. In addition, John farms another 100 acres of organic land that he does not own. The farm spans two properties located about half a mile apart. The property where John lives has generally higher-quality soil, while the second has been steadily improved since he purchased it and continues to benefit from ongoing land rehabilitation efforts. The operation has been certified organic since 2005 and has participated in the Real Organic Project since 2021.
The heart of John’s approach is a commitment to the health, happiness, and longevity of his animals and the land management practices that make that possible. His farming vision centers on increasing productivity and building soil fertility, with a particular interest in finding crops that serve double duty: first as hay, then as grazing ground. In past summers, John focused primarily on grazing and making hay from local grasses, but now he is shifting to incorporate summer annuals into his hay production. Sunn hemp (Crotalaria juncea), a warm-season legume known for its nitrogen-fixing capacity and rapid biomass accumulation, is a crop that is common in the south, but is not well tested in northern climates.
Finding a Dual-Purpose Forage Crop
One of John’s goals is to rehabilitate fields that have historically been underproductive. The second property, in particular, was farmed intensively for roughly a century, its fertility depleted over generations. While John has made meaningful progress, there is still work to do. He identified several areas that are weedy or low-yielding and began looking for crops that could build soil health while also generating real economic value through hay production.
Sunn hemp stood out as a strong candidate. A tropical legume that thrives in warm conditions, sunn hemp fixes atmospheric nitrogen, suppresses weeds, and produces substantial biomass in as little as 60 days. For a farm where land improvement and forage production are equally important, the crop’s dual-use potential was a clear draw. John had previously explored interseeding it with companion grasses through a SARE-funded grazing project at the University of Maine involving Japanese millet, which gave him a useful starting point.
The core question John wanted to answer was practical: does interseeding sunn hemp with Japanese millet produce higher quality or greater quantities of hay than growing sunn hemp alone? Japanese millet is a fast-growing warm-season grass with a solid track record in Maine. John hypothesized that the two crops might complement each other: the millet adding structure and bulk, and the sunn hemp contributing protein and nitrogen. Getting real data from his fields, under his management, was the motivation behind applying for OFRF’s Farmer Led Trials program.
On-Farm Trial Plan
Source: University of MaineSunn hemp in bloom.
With technical support from OFRF, John designed a replicated on-farm trial comparing two hay crop treatments: sunn hemp grown as a pure stand, and sunn hemp interseeded with Japanese millet. The trial follows a randomized complete block design with four replications of each treatment, for a total of eight plots. Each plot measures 80 feet long by 13 feet wide, sized to match John’s 13 foot seed drill and ensure at least one round bale can be harvested per plot. All plots are located within a single long field on the farm to minimize variability. Seeding rates are set at 50 pounds/acre for sunn hemp in pure stand, and 25 pounds/acre each for sunn hemp and Japanese millet in the mixture, with sunn hemp seed inoculated with an OMRI-listed cowpea-type inoculant prior to planting.
Data collection will include stand density counts after emergence, biomass sampling from two 2 foot by 2 foot quadrats per plot, round bale weight estimates at harvest, and forage quality analysis through DairyOne’s standard NIR forage package covering dry matter, protein, fiber fractions, and other key nutritional components. This combination of yield and quality data will give John and the OFRF team a well-rounded picture of how the two treatments compare.
Trial Updates
The 2025 trial season got off to a difficult start. An unusually cold and wet spring pushed planting well past the original mid-June target, and a series of tractor breakdowns made it impossible to get into the field. By early August, the window for planting a 60-day crop had closed and frost risk made it too late to proceed. After consulting with the OFRF team, John and the program agreed to extend the trial into the 2026 season. John is holding onto his seed and plans to run a germination test before next planting season. In the meantime, he prepared the tilled ground with a winter-kill oat cover crop to keep the land ready for spring. John remains enthusiastic about the trial and is planning to move forward in the coming season.
Source: O'Meara Family FarmThe cattle herd at O’Meara Family Farm.
“I wanted to be in the FLT program because decades of farming has taught me that another set of eyes on a topic—especially expert eyes—often leads to creative ideas and better on the ground outcomes.”
– John O’Meara, FLT Program Participant
Source: O'Meara Family FarmA newly tilled bed, ready for seeding.
This is part of a series of blogs highlighting farmers who are participating in OFRF’s Farmer-Led Trials program. Farmers receive technical support to address their production challenges through structured on-farm trials. To learn more about OFRF’s Farmer-Led Trials Program, visit our website page at https://ofrf.org/research/farmer-led-research-trials/
To learn more about sunn hemp as a forage and cover crop, visit the USDA Plant Guide for Sunn Hemp.
To learn more about O’Meara Family Farm, visit their Facebook.





























