Fall dry matter yield and nutritive value of winter rye, wheat, and triticale cultivars in Wisconsin

Authors: COBLENTZ, WAYNE; AKINS, MATTHEW - UNIVERSITY OF WISCONSIN; CAVADINI, JASON - UNIVERSITY OF WISCONSIN

Submitted to: Crop, Forage & Turfgrass Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/28/2020
Publication Date: 12/15/2020
Citation: Coblentz, W.K., Akins, M.S., Cavadini, J.S. 2020. Fall dry matter yield and nutritive value of winter rye, wheat, and triticale cultivars in Wisconsin. Crop, Forage & Turfgrass Management. https://doi.org/10.1002/cft2.20075.
DOI: https://doi.org/10.1002/cft2.20075

Interpretive Summary: Recent emphasis on use of cover crops to improve soil health, limit soil erosion, and alleviate nutrient runoff has increased the use of cereal-grains as forages throughout the north-central USA. These forages normally possess requirements for cold vernalization, and are terminated either with a non-selective herbicide treatment in the spring, or by a spring harvest as silage, and then followed by a double-crop of corn or soybeans. Our objectives were to evaluate the fall (vegetative) forage yield and nutritive value of winter wheat, rye, and triticale cultivars harvested on dates ranging from mid-October through early-December, and subsequently to examine the residual effects of fall harvest date on forage regrowth potential the following spring. Fall DM yield of winter cereals in central Wisconsin varied with weather conditions, but can approach 1 ton/acre in some years. Utilization of this forage by grazing livestock is likely to be complicated by the potential for pugging of wet, heavy soils by livestock, or by the onset of significant lasting snowfall. The nutritive value of these fall forages is excellent, as reported for other parts of the US, with no clear advantages attributed to any of the species examined. In particular, concentrations of water-soluble carbohydrates and whole-plant ash appear to be major drivers (positive and negative, respectively) of variations in forage energy density. Spring and total (fall + spring) yields for cereal rye often were less than observed for triticale or wheat; however, late-winter or early-spring weather extremes complicated any definitive interpretation of this response.

Technical Abstract: Objectives for this research were to evaluate the fall forage yield and nutritive value of winter wheat, rye, and triticale cultivars in central Wisconsin, and examine the residual effects of fall harvest date on forage regrowth the following spring. The trial was conducted over three years with 12 treatments and six blocks (replications) arranged in a randomized complete block design, creating 72 plots/yr. Treatments consisted of a factorial arrangement of three winter-cereal species [rye (Secale cereale L.), triticale (X Triticosecale Wittmack), and wheat (Triticum aestivum L.) and four targeted fall harvest dates (15 October, 1 November, 15 November, 1 December). Fall dry matter yields ranged from 1819 to 1994, 465 to 957, and 1144 to 1357 lbs/acre across the three species during 2017, 2018, and 2019, respectively, but consistent advantages for any single species were difficult to discern. There was little evidence suggesting fall yields were improved consistently by delaying the harvest date beyond 15 October. Although the nutritive value of winter-cereals was excellent, variations in net energy of lactation (NEL; Mcal/kg) were positively correlated (P = 0.001) with water-soluble carbohydrates for 2018 (r = 0.570) and 2019 (r = 0.456). Whole-plant ash was negatively associated with NEL, yielding significant (P < 0.001) correlations for 2017 (r = -0.967), 2018 (r = -0.878), and 2019 (r = -0.656). Spring yields of cereal rye were reduced (P < 0.05) compared to other species in 2019 and 2020; however, no differences (P > 0.05) among species were detected in 2018.