The production of hybrid carrot seed is difficult because of the indeterminacy of ripening and the tendency to shatter mature seeds. The umbel (flat-top cluster) inflorescences (seedheads) of carrots mature sequentially over a 3-4 week period. The primary (king) umbel matures first, followed by the secondary and tertiary umbels. The standard harvest method is to swath when the primary and many of the secondary umbel have reached maturity. After 3-7 days of drying in the windrow the material is run through a combine. Some of the secondary umbels and most of the tertiary umbels are immature, producing seed with poor viability or failing to produce any viable seed at all. If the crop is direct combined, even less viable seed is recovered. Growers are presently unable to harvest all of the potential seed that the carrot plants are capable of producing. The same is true for wildflowers such as western yarrow. This plant has corymb inflorescences (flat-top clusters similar to umbels) that also mature over a 3-4 week period. Stands will have brown (mature), green (developing) and white (still flowering) inflorescences at the same time. With single event harvests, such as direct combining or swathing and combining from a cured windrow, only a fraction of the potential seed production is captured and some of that seed may have low viability. Native Seedsters, Inc. proposes to test the feasibility of Seedster technology to difficult-to-harvest seed of a dry vegetable (carrot) and a native wildflower (western yarrow). The patented Seedster technology consists of counter-rotating brush and combing drum which create a pinch-point where mature seed are dislodged (plucked) from the inflorescence, while immature inflorescences are left intact and allowed to continue to mature and be harvested at a later time. Seedster technology makes it possible for multiple harvests; harvesting seed as it matures, thus increasing the quantity and quality of seed captured from non-uniform ripening crops. Trials will be conducted using a highly adjustable Test-Bed model Seedster, varying pinch-point spacing, brush bristle density, combing drum surface configurations, brush and comb rotating speed and forward ground speed. If the Seedster is able to increase harvestability of carrot and yarrow then this technology may be applied to other difficult-to-harvest dry vegetables such as lettuce and onion and native wildflowers such as aster, biscuitroot and buckwheat that are indeterminate in ripening and are prone to shatter. The Seedster was originally designed to harvest grass seed, but potentially can be used to harvest dry vegetables, wildflowers and specialty biofuel crops such as camelina and meadow foam. OBJECTIVES: Native Seedsters, Inc. proposes to test the feasibility of using Seedster technology to harvest seed of hybrid carrots (Daucus carota var. sativus)(Apiaceae family) and western yarrow (Achillea millefolium) (Asteraceae family). Carrots (a dry-vegetable) have an umbel inflorescence and yarrow (a native wildflower) has a corymb inflorescence, both flat topped terminal clusters. Both species are characterized by indeterminacy of seed ripening and a tendency to shatter mature seed. Carrots have three orders of umbels which mature sequentially over a three to four week period. The primary (king) umbel matures first followed by the secondary and tertiary umbels. Yarrow also ripens over a three to four week period having brown (mature), green (developing) and white (flowering) inflorescences at the same time. Standard harvest methods for both species is to swath the stand when the earliest maturing inflorescences are about to shatter (approximately 20% seed moisture). Developing inflorescences may continue to mature in the windrow during the 3-7 day drying period, but most of the immature inflorescences either produce low viability seed or fail to develop any seed at all. With direct combining even less viable seed is attained. Seedster technology uses counter-rotating horizontal brush and combing drum that create a pinch-point that pluck the mature seed of interest. With Seedster technology it is anticipated that it will be possible to harvest the mature seed while leaving the developing inflorescences intact, allowing them to continue to mature. Multiple passes can be made as inflorescences continue to mature. Seedster components will be configured to achieve a balance between firm removal of ripe seed and gentle, non-damaging treatment of the immature inflorescences. If Seedster technology proves to be an effective harvest alternative for carrots and yarrow, the technology can be expanded to other difficult-to-harvest dry vegetables such as lettuce (Lactuca )and onion (Allium) and other wildflowers such as biscuitroot (Lomatium), aster (Aster/Symphyotrichum) and buckwheat (Eriogonum). An alternate harvesting method that would result in higher yields and greater seed quality would significantly impact the vegetable and wildflower seed production industry
