Throughout the Southern Great Plains, wheat is managed frequently as a dual-purpose crop, but this production paradigm is not necessarily applicable throughout other regions of the United States, and a wider array of management options can be considered for forage-only uses of cereal grains. Our objectives were to assess the fall-growth potential of wheat (Triticum aestivum L.), triticale (X Triticosecale Wittmack), and oat (Avena sativa L.) cultivars in Wisconsin, and then to further evaluate and compare the fiber composition and TDN of these fall-grown forages. For 2006, yields of DM for all cultivars increased quadratically (P < or = 0.048) over fall harvest dates, reaching a maximum of 3,967 kg/ha for Ogle oat. All oat cultivars exhibited stem elongation and also displayed a collective 2 to 1 yield advantage over vegetative wheat cultivars on the final (October 30) harvest date. Growing conditions were more favorable during 2007, and yields were improved for all cultivars. Yields of DM for all cultivars increased quadratically (P < or = 0.021) across harvest dates, and oat cultivars maintained the identical 2 to 1 yield advantage over wheat cultivars (6,275 vs. 3,203 kg/ha) that was observed for 2006. Triticale exhibited yields intermediate between oat and wheat during both years. Concentrations of NDF increased quadratically (P < or = 0.012) across harvest dates for all cultivars during both years of the experiment; however, these increases occurred primarily between mid September and early October with limited responses thereafter. Oat and triticale cultivars had greater (P < 0.001) concentrations of NDF than wheat cultivars on 5 of 6 harvest dates throughout the experiment. Estimates of TDN exhibited various polynomial responses to harvest date during 2006, but the magnitude of these changes was relatively small. During 2007, TDN declined linearly (P < or = 0.038) for grain-type oat, but no relationship with harvest date was observed for other cultivars (P > or = 0.072), including forage-type oat. Although TDN estimates generally were relatively static across harvest dates, the concentrations of truly digestible components constituting the total TDN pool were quite fluid. Generally, reductions of truly digestible CP were offset by increases in truly digestible nonfiber carbohydrate, truly digestible fiber, or both. The relatively stable energy densities for cereal-grain cultivars observed across harvest dates suggest that a broad window of opportunity exists for usage, including a single harvest as silage.

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Forage grass cultivars are often grown in binary mixtures with forage legumes. Because performance of grass‐legume mixtures cannot be reliably predicted from pure stand information of the components, testing of grass‐legume mixtures is necessary to develop reliable mixture recommendations. The objectives of this study were to evaluate a large number of cultivars of several temperate forage grasses in binary mixtures with alfalfa (Medicago sativa L.) for ground cover potential in a range of Wisconsin environments, and to develop an efficient cultivar screening program. Cultivars of nine species (146 total cultivars) were grown in at least one of five experiments. Experiments were seeded in spring of 1985 and 1986 at one of four locations divergent in both soil type and latitude. Grass persistence was determined after three growing seasons by evaluating the percentage of ground cover remaining. Grass species and genera varied in percentage ground cover, but were subject to interactions with years and locations. In general, orchardgrass (Dactylis glomerata L.) and tall fescue (Festuca arundinacea Schreb.) had the highest ground cover (76%). Variation in ground cover among cultivars was detected in all species except diploid perennial ryegrass (Lolium perenne L.), tetraploid intermediate ryegrass (L. hybridum), and festulolium (Festulolium braunii K.A.). Cultivars interacted with locations and/or years for all species, except reed canary grass (Phalaris arundinacea L.). Cultivar ✕ location interactions appeared partially due to latitude for smooth bromegrass (Bromus inermis Leyss.), tall fescue, and most ryegrasses, and to soil type for timothy (Phleum pratense L.). Conclusions regarding the development of a cultivar testing program differed for most species. A reasonable compromise in Wisconsin, to allow for testing each species in common trials, would be to select one southern and one northern test site.

We conducted three experiments to determine the influence of mechanical processing on corn silage utilization by lactating dairy cows. Total mixed rations contained either unprocessed or processed corn silage harvested between 1/4 and 3/4 milk line. In trial 1, 12 multiparous Holstein cows were used in a replicated double switchback design with 21-d periods. Intake of dry matter (DM) was increased 1.2 kg/d by processing, but milk yield was unaffected. Processing did not affect apparent total-tract DM digestibility, but processing tended to lower starch and corn excretion in feces and reduced concentration of sieved corn kernel particles in feces. In trial 2, 42 Holstein cows were used in an 18-wk randomized complete-block design. Intake of DM and milk yield were unaffected by processing, but milk fat percent was increased 0.35 percentage units by processing. Processing tended to increase total-tract digestibility of starch, but reduced organic matter, crude protein, and neutral detergent fiber digestibilities. In trial 3, 30 Holstein cows were used in a 15-wk randomized complete block design. There was no influence of mechanical processing on intake or lactation performance in this trial. Despite indications of increased starch digestion in two trials and increased DM intake in one trial, effects of processing corn silage on lactation performance were minimal with corn silage at the maturity and moisture contents used in these trials.