Viability of Weed Seeds in Feed Pellet Processing
Journal of range management
Federal and state agencies in several western states now require the use of noxious weed-free or noxious weed seed-free forage to hinder the spread of noxious weeds. Forage can be certilied as noxious weed-free through state administered programs. Processed feeds such as pellets or cubes made from noncertified hay and uncleaned grain are some of the forage products that may be potential sources of weed infestations. This study was conducted to determine levels of weed seed contamination in
... ntamination in alfalfa hay/grain feed pellets manufactured with commercialgrade equipment. Seeds of whitetop [Cur-drubu (L.) Hand.], spotted knapweed (Centaurea maculosa Lam.), Canada thistle [Cirsium arvense (L.) Stop.], leafy spurge (Euphorbiu es& L.), and common yellow sweetclover [Melilohrs offiinufis (L.) Lam.] were added in known quantities to alfalfa/grass mixed hay and to barley. The hay was ground in a hammermill through a screen with 7.9-mm diameter perforations, and the barley was ground to pass through a Z&mm screen. In a second experiment, uncertified 'Ladak 65' alfalfa (Medicago sah'vu L.) seeds were ground with alfalfa/grass mixed hay in a hammermill and extruded through a pellet die before being ground in another hammermill with barley grain followed by extrusion through a pellet die. The Montana Department of Agriculture collected pelleted feed from various manufacturers in the state during 1993 and 1994 to estimate potential weed contamination frequency. Grinding of weed seeds with alfalfa hay or barley grain reduced emergence by 98 to 100%. Grinding and pelleting reduced emergence of alfalfa seed by over 99 46. Weed seedlings emerged from 11% of random feed pellet samples collected from Montana manufacturers. Rigorous processing such as occurs when manufacturing hay/grain pellets reduces the risk of disseminating weed seeds from pelleted feed.