Technical Note: A rotary seed processor for removing pubescence from seed of prairie grasses

Abstract

Many of the perennial prairie grasses that are used in restoration plantings in the central Great Plains have seed appendages such as awns and pubescence that make seed now through planters difficult. We have developed a rotary seed processor that efficiently processes small breeder or experimental lots of seed that can then be easily planted with small plot cone planters or conventional planters. The processor consists of a metal cylinder that is lined with corrugated rubber and a rotating center shaft with rubber paddles. Processing can be controlled by varying shaft rotation speed and processing time. A top-opening, full length trap door allows for easy loading and the cylinder can be inverted to dump out processed seed. The processor has been used successfully for several years on big bluestem [Andropogon gerardii Vitman], indiangrass [Sorghastrum nutans (L) Nash], little bluestem [Schizachyrium scoparium (Michaux) Nash], prairie sand reed [Calamovilfa longifolia (Rook.) Scribner] , and blue grama [Bouteloua gracilis (Willd. ex Kunth) Lagascaex Griffiths] seed. By removing seed appendages and pubescence, seed bulk is reduced and seed density and flow ability are improved. The processing operation is relatively gentle and seed germination per unit weight of seed is improved.