News & Articles

Montana’s Native Seedsters, Inc. Achieves Commercial Success

USDA - SBIR Impact
March 2008

Native grass is important for the restoration or reclamation of burned, mined, or otherwise disturbed lands, and the native seed industry is growing rapidly to meet the increasing demand for more seed species in commercial quantities. However, the seed morphology of many important species of native grasses makes the seed difficult to harvest, which results in limited supplies and high prices. Combines and other conventional harvesters, such as strippers, are often unable to effectively carry out one or more of the key steps of seed harvest: 1) dislodgement, 2) separation, 3) conveyance, and 4) offloading.

In a first Phase I/Phase II USDA–SBIR set of projects, Arbuckle Ranch, Inc. developed low–cost technology that is easy to manufacture and maintain, and is highly effective at dislodging (or “plucking”) difficult-to-harvest native grass seeds. This technology involves a brush and combing drum that counter-rotate. The next step find a way to efficiently convey the increased volume of dislodged seed to a collection receptacle. The challenge was to engage the seed in flight to prevent it from cohering and plugging the system because of awns, barbs, and other features.

In a second Phase I/Phase II USDA–SBIR set of projects, the Arbuckle Ranch team developed two models to address pneumatic conveyance needs. To be commercially viable each had to mesh smoothly with Native Seedster's unique proprietary seed dislodgement mechanism. In 2006, Arbuckle Ranch, Inc. spun off a wholly-owned subsidiary, Native Seedsters, Inc. (NSI), to produce and market grass seed harvesters.

The first pneumatic conveyance system (PCS) model used a vacuum fan and cyclone separator approach. The PCS vacuum engaged seed in flight and transported it through tubing for bagged or bulk collection on a trailer. The trailer could easily offload a standard 3’x3’x4’ seed tote bag. NSI commercially released a finished harvester in July 2007, and two units were sold and delivered later that year. The first sale resulted in the customer saying of the harvester, “As I told you after our meeting, I believe your machine is probably the best harvester available for native seed that I’ve found” while harvesting switchgrass.

The Seedster’s patented seed dislodgement technology permits higher ground speed than a traditional combine, allowing it to cover more acres during the harvest window. In-field separation is eliminated because seed is plucked with minimal impurities. To effectively separate seed and chaff a combine must slow its ground speed. The Seedster PCS-Vac handles the increased seed flow requirements, thus moving at a faster speed. This embodiment of technology effectively performs all four stages of harvesting for grass seed species that are difficult to harvest by conventional combine or strippers.

Seedster developed its second pneumatic conveyance technology in the last months of 2007, at the conclusion of Phase II. In this model, rather than using vacuum suction, a compact “air boost” mechanism supplements the airflow generated by the brush comb mechanism that conveys dislodged seed to a hopper. Seed dislodgement, seed conveyance, and seed collection are consolidated in one loader-mounted header. This model is referred to as the “Front Hopper Seedster,” or the “Seedster FH.” Conduits and components were developed during the summer months by testing on Russian wild rye and camelina. Tests using basin big sagebrush, Artemisia tridentata, in November and December helped fine-tune the shapes and conduits. Sagebrush seeds, numbering 2 million per pound, were ideal to validate the design of the pneumatic flow.

Native Seedsters agreed to design for Ceres, Inc. a prototype seed harvester specialized to harvest upland and lowland switchgrass. If the prototype (May 2008 delivery) meets specifications, Ceres will purchase several Switchgrass Seedsters. Ceres, an energy crop company, plans to sow thousands of acres of switchgrass, high-biomass sorghum, and other crops over the next 3 years to support a next-generation bio-refinery near St. Joseph, MO.