Submitted to: American Forage and Grassland Council Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: May 1, 2005
Publication Date: June 11, 2005
Citation: Cassida, K.A., Turner, K.E. 2005. Overseeded forage brassica yield and subsequent grass sward recovery in appalachian hill pastures. American Forage and Grassland Council Conference Proceedings, 14:152-165. Interpretive Summary: Forage brassicas can provide high-quality forage for sheep and goats, but correct timing of planting is essential for good yields. Also, the sod suppression that is necessary for good brassica establishment into a pasture may damage grass yields thereafter. Forage rape and turnips overseeded into herbicide-suppressed grass pasture in April, June, July, or August in West Virginia provided forage from May to late November. However, grass yields were reduced up to 61% in the year following brassica overseeding, and the magnitude of yield loss increased with later overseeding dates. This work is useful because it shows that brassicas can provide forage over a wide time period and are better suited to overseeding into hill pastures that are in need of renovation than into productive pastures. The work will benefit livestock producers and resource managers working to improve efficiency of livestock production in Appalachia.
Technical Abstract: Forage brassicas can provide high-quality forage for small ruminants, but yields are affected by time of planting and sod-suppression may damage swards. We evaluated brassica yield and grass sward recovery in the subsequent year for forage rape (Brassica napus L.) and turnip (B. rapa L.) overseeded into an glyphosate-suppressed orchardgrass-based (Dactylis glomerata L.) Appalachian hill pasture. Design was a split-split plot with planting date (April, June, July, or August) as main plot, cultivar (‘Barkant’ turnip and ‘Barnipoli’ rape) as subplot, and harvest date (6, 9, 12, 15, and 18 wk after planting) as sub-subplot. Turnip failed to establish with July planting. All plots were lost to freezing by late November. Rape yielded up to 3941 lb/acre with July planting and turnip up to 2731 lb/acre with April planting. Rape yields increased at each harvest date within most plantings, but turnip yields tended to plateau or decline. Turnip regrowth was greater in April than in June plantings. Grass sward yields were reduced in the year following brassicas, and the magnitude of reduction increased with later overseeding dates. Mid- to late-summer overseeding resulted in up to 61% loss of subsequent-year forage productivity. Brassica overseeding with glyphosate-induced sod suppression on Appalachian pastures is contraindicated on a productive meadow, but may be useful as the first step of grassland renovation for a meadow in poor condition.