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Getting agricultural producers to make changes to their operations is difficult, especially related to complex systems such as the water cycle on managed agricultural lands. We surveyed participants who had watched a rainfall simulator demonstration during the summer of 2015. Results indicate that the demonstration was effective in providing educational outreach on the impact of the water cycle and prompting the adoption of conservation practices and monitoring techniques among producers. The study reinforces the importance in conservation education of learning experiences involving simulation, observation, and group discussion. Our findings may be applicable not only to Extension professionals working with agricultural producers but also to those involved in encouraging conservation practices among other audiences.

Selection at the seedling stage in grass breeding would be useful if seedling traits were correlated to desired agronomic traits of mature plants. Objectives of this study were to determine if seedlings from big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) populations that differ genetically in seedling tiller number differ in mature plant (i) morphological characteristics, (ii) forage yield managed by a three-cut harvest system or a single end-of-season harvest, and (iii) leaf elongation rate. Field experiments were conducted on a Kennebec silt loam soil (fine-silty, mixed, superactive, mesic Cumulic Hapludolls). In addition, greenhouse studies were conducted in 1999 through 2001. Seedlings from big bluestem and switehgrass populations that differed for seedling tiller numbers were transplanted into spaced-planted field nurseries and greenhouse pots for study. Leaf width, leaf length, plant height, number of tillers per plant, yield, and leaf elongation rate were measured. Mature plant morphological characteristics differed between multiple-tiller and single-tiller plant types for both big bluestem and switchgrass. There were no differences in forage yield for big bluestem plant types. Switchgrass single-tiller plant types yielded 200 g [plant.sup.-1]) more than multiple-tiller types when harvested only once. Leaf elongation rate was 22 and 28% greater for single-tiller types vs. multiple-tiller types for big bluestem and switchgrass, respectively. Selection at the seedling level for tiller number appears to be an effective method to develop genotypes differing in yield per tiller, which has been shown to affect herbage yield when grown in swards., SELECTION at the seedling stage in grass breeding would be extremely useful if seedling traits were correlated to desired agronomic traits of mature plants. Selection for large leaf size in [...]

Selection at the seedling stage in forage grass breeding would be extremely useful if seedling traits are highly heritable and correlated to desired agronomic traits. Objectives of this study were to determine the response to selection for high shoot weight and divergent selection for seedling tiller number in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) seedlings and obtain estimates of realized heritability for these traits. Base populations were breeding populations of 'Pawnee' big bluestem and 'Pathfinder' switchgrass. Divergent selection for single or multiple (three or more) tiller(s) 6 to 8 wk after planting in a greenhouse produced four populations [big bluestem high seedling weight, multiple tiller (BBMT); big bluestem high seedling weight, single tiller (BBST); switchgrass high seedling weight, multiple tiller (SWMT); and switchgrass high seedling weight, single filler (SWST)], which were planted in isolated polycross nurseries. Seed from polycross nurseries was used to conduct a second cycle of selection. Populations were evaluated in greenhouse studies for fresh weight and filler number of seedlings. Seedling fresh weight was increased in BBST and SWST Cycle 2 populations, and divergent selection for tiller number resulted in populations significantly different from the base population. Realized heritability estimates for seedling tiller number in big bluestem and switchgrass were 0.26 and 0.23, respectively. The effect of genetic modification of seedling filler number and shoot weight on establishment under field conditions and on mature plant phenotypes will need to be determined., GRASS DEVELOPMENTAL morphology determines the expression of desirable traits of species utilized as forage. Most grass breeding programs are limited in their selection pressure by the limited number of plants [...]

Selection at the seedling stage in grass breeding would be extremely useful if seedling traits are correlated to desired agronomic traits. The objective of this study was to evaluate seedling morphological development, plant growth, and field establishment of big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) populations that were developed by divergent selection for seedling tiller number while selecting for high shoot weight. Six populations were evaluated: (i) 'Pawnee' big bluestem base, (ii) 'Pathfinder' switchgrass base, (iii) big bluestem multiple tiller, (iv) big bluestem single tiller, (v) switchgrass multiple tiller, and (vi) switchgrass single tiller. Field plots were seeded in spring 1999 and 2000 in a Kennebec silt loam (fine-silty, mixed, superactive, mesic Cumulic Hapludolls). Plants were excavated and evaluated during the growing season for shoot weight, root weight, and morphological stage of shoot and root systems. There were no major population differences in shoot weight, root weight, and morphological root stage. Shoot stage was higher for multiple tiller populations than single tiller populations 6 wk after emergence. Stand counts for all populations exceeded 10 seedlings per linear m of row, which is considered an acceptable stand density, and there were no consistent differences among populations. Populations divergently selected for seedling tiller number did not differ in ability to become established under field conditions because root systems apparently were not altered by the selection for seedling tiller number and weight. These results suggest that selection for high shoot weight did not improve seedling vigor in the field., SEEDLING ESTABLISHMENT is a major limitation for incorporating improved cultivars of native warm-season grasses into a forage system. Lack of successful establishment of perennial forage grasses has been attributed to [...]

The quantity of grass-root exudates varies by season, suggesting temporal shifts in soil microbial community composition and activity across a growing season. We hypothesized that bacterial community and nitrogen cycle-associated prokaryotic gene expressions shift across three phases of the growing season. To test this hypothesis, we quantified gene and transcript copy number of nitrogen fixation (nifH), ammonia oxidation (amoA, hao, nxrB), denitrification (narG, napA, nirK, nirS, norB, nosZ), dissimilatory nitrate reduction to ammonia (nrfA), and anaerobic ammonium oxidation (hzs, hdh) using the pre-optimized Nitrogen Cycle Evaluation (NiCE) chip. Bacterial community composition was characterized using V3-V4 of the 16S rRNA gene, and PICRUSt2 was used to draw out functional inferences. Surprisingly, the nitrogen cycle genes and transcript quantities were largely stable and unresponsive to seasonal changes. We found that genes and transcripts related to ammonia oxidation and denitrification were different for only one or two time points across the seasons (p < 0.05). However, overall, the nitrogen cycling genes did not show drastic variations. Similarly, the bacterial community also did not vary across the seasons. In contrast, the predicted functional potential was slightly low for May and remained constant for other months. Moreover, soil chemical properties showed a seasonal pattern only for nitrate and ammonium concentrations, while ammonia oxidation and denitrification transcripts were strongly correlated with each other. Hence, the results refuted our assumptions, showing stability in N cycling and bacterial community across growing seasons in a natural grassland. [ABSTRACT FROM AUTHOR]

Brassica cover crops are an option for producers to incorporate into their cropping system to improve soil health and also provide a feed resource for cattle. While brassica cover crops have been widely used for grazing cows, their use as a backgrounding feedstuff is relatively unknown. The objective of this study was to determine the impact of feeding a brassica cover crop mixture during backgrounding on live animal performance and carcass characteristics. A total of 30 Angus-based steers were assigned to one of two dietary treatments during backgrounding 1) ad libitum access to a diet containing freshly cut brassica cover crop forage (CC) containing radish, turnip, rapeseed, rye grass, and a liquid supplement or 2) common Midwestern dry lot growing diet containing silage, soybean meal, grass hay, and a liquid supplement (CON). Steers were assigned to electronic feed bunks (Insentec RIC, Hokofarm Group; Marknesse, the Netherlands) for collection of individual feed intake. Diets were formulated to be nutritionally similar on a dry matter basis. Steers were paired by weight across treatments and pair fed. Dry matter intake (DMI) was calculated daily for steers in the CC treatment and the following day, CON steers were allowed access to an equal amount of dry matter using the Insentec RIC system. Steers were weighed weekly and backgrounded for 44 days before transitioning to a common finishing diet and weighed every 28 days. Steers were harvested at an estimated average backfat thickness of 1 cm. Standard carcass data were measured and strip loins and shoulder clods were collected. Instrumental and subjective color were measured on ground beef for 8 days and instrumental color was measured on strip steaks for 11 days. Treatment did not influence carcass characteristics, average daily gain, and DMI (P > 0.17). However, CON steers exhibited increased gain to feed ratio (P = 0.02). Additionally, a treatment by day interaction was observed for ground beef discoloration as the CC treatment displayed increased discoloration on days 4, 6, and 7 of case life (P < 0.01). These data indicate that brassicas may be utilized in a backgrounding diet without negatively impacting carcass characteristics but may decrease case life of ground beef. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to measure rates of ruminal disappearance, and energy and nutrient availability and N balance among cows fed corn husks, leaves, or stalks. Ruminal disappearance was estimated after incubation of polyester bags containing husks, leaves or stalks in 2 separate ruminally cannulated cows in a completely randomized design. Organic matter (OM) that initially disappeared was greatest for stalks and least for husks and leaves (P < 0.01), but amounts of NDF that initially disappeared was greatest for husks, intermediate for stalks, and least for leaves (P < 0.01). Amounts of DM and OM that slowly disappeared were greatest in husks, intermediate in leaves, and least in stalks (P < 0.01). However, amounts of NDF that slowly disappeared were greatest in leaves, intermediate in husks, and least in stalks (P < 0.01). Rate of DM and OM disappearance was greater for leaves, intermediate for husks and least for stalks, but rate of NDF disappearance was greatest for stalks, intermediate for leaves, and least for husks (P < 0.01). Energy and nutrient availability in husks, leaves, or stalks were measured by feeding ruminally cannulated cows husk-, leaf-, or stalk-based diets in a replicated Latin square. Digestible energy lost as methane was less (P = 0.02) when cows were fed leaves in comparison to husks or stalks, and metabolizable energy (Mcal/kg DM) was greater (P = 0.03) when cows were fed husks and leaves compared with stalks. Heat production (Mcal/d) was not different (P = 0.74) between husks, leaves, or stalks; however, amounts of heat produced as a proportion of digestible energy intake were less (P = 0.05) among cows fed leaves in comparison to stalks or husks. Subsequently, there was a tendency (P = 0.06) for net energy available for maintenance from leaves (1.42 Mcal/kg DM) to be greater than stalks (0.91 Mcal/kg DM), and husks (1.30 Mcal/kg DM) were intermediate. Nitrogen balance was greater when cows were fed leaves, intermediate for husks, and least for stalks (P = 0.01). Total tract digestion of NDF was greater (P < 0.01) for husks and leaves compared with stalks. Husks had greater (P = 0.04) OM digestibility in comparison to stalks, and leaves were intermediate. Apparently, greater production of methane from husks in comparison to leaves limited amounts of energy available for maintenance from husks even though total-tract nutrient digestion was greatest when cows were fed husks or leaves. [ABSTRACT FROM AUTHOR]

Six ruminally cannulated cows (570 ± 73 kg) fed corn residues were placed in a 6 × 6 Latin square to evaluate predictions of diet composition from ruminally collected diet samples. After complete ruminal evacuation, cows were fed 1-kg meals (dry matter [DM]-basis) containing different combinations of cornstalk and leaf and husk (LH) residues in ratios of 0:100, 20:80, 40:60, 60:40, 80:20, and 100:0. Diet samples from each meal were collected by removal of ruminal contents after 1-h and were either unrinsed, hand-rinsed or machine-rinsed to evaluate effects of endogenous compounds on predictions of diet composition. Diet samples were analyzed for neutral (NDF) and acid (ADF) detergent fiber, acid detergent insoluble ash (ADIA), acid detergent lignin (ADL), crude protein (CP), and near infrared reflectance spectroscopy (NIRS) to calculate diet composition. Rinsing type increased NDF and ADF content and decreased ADIA and CP content of diet samples (P < 0.01). Rinsing tended to increase (P < 0.06) ADL content of diet samples. Differences in concentration between cornstalk and LH residues within each chemical component were standardized by calculating a coefficient of variation (CV). Accuracy and precision of estimates of diet composition were analyzed by regressing predicted diet composition and known diet composition. Predictions of diet composition were improved by increasing differences in concentration of chemical components between cornstalk and LH residues up to a CV of 22.6 ± 5.4%. Predictions of diet composition from unrinsed ADIA and machine-rinsed NIRS had the greatest accuracy (slope = 0.98 and 0.95, respectively) and large coefficients of determination (r2 = 0.86 and 0.74, respectively). Subsequently, a field study (Exp. 2) was performed to evaluate predictions of diet composition in cattle (646 ± 89 kg) grazing corn residue. Five cows were placed in 1 of 10 paddocks and allowed to graze continuously or to strip-graze corn residues. Predictions of diet composition from ADIA, ADL, and NIRS did not differ (P = 0.99), and estimates of cornstalk intake tended to be greater (P = 0.09) in strip-grazed compared to continuously grazed cows. These data indicate that diet composition can be predicted by chemical components or NIRS by ruminal collection of diet samples among cattle grazing corn residues. [ABSTRACT FROM AUTHOR]

A rapid approach is needed for determining the effectiveness of precision conservation on soil health as evaluated using CO2 and NH3 emissions. This study demonstrated an approach for calculating CO2-C and NH3-N emissions and associated rate constants when feces were applied to bare soil or soil + vegetation. In addition, point CO2-C emission measurements were compared with near continuous measurements. The CO2-C emissions were measured at 2 h intervals over 20 d, whereas ammonia volatilization was measured three times daily for 7 d. Total CO2-C emissions over 20 d were 5% lower [186 g CO2-C (M2 × 20 d)-1] than point measurement collected at 1100 h every day (197 g CO2-C (M2 × 20 d)-1), and about 10% lower than if collected every 2 d [206 g CO2-C (M2 × 20 d)-1]. A Fast Fourier transformation (FFT) showed that temperature and NH3-N and CO2-C emissions followed diurnal cycles and that they were in-phase with each other. Over 7 d, 20% of feces NH4-N was volatilized and that this loss was similar when feces were applied over vegetation or mixed into the soil. Feces additions increased the amplitude of the CO2-C diurnal cycle, and the fecal-C first-order rate degradation constants were higher when mixed with soil [0.0109 &3177; 0.0043 g(g×d)-1, p = 0.1] than applied over vegetation [0.00454 &3177; 0.00336 g(g×d)-1, p = 0.1]. [ABSTRACT FROM AUTHOR]

Switchgrass (Panicum virgatum L.) is an important candidate for bioenergy feedstock production, prompting significant efforts to increase the number of breeding programs and the output of those programs. The objective of this experiment was to determine the potential utility of natural selection for survivorship in switchgrass swards as a tool for improving efficiency of progeny-test-based recurrent selection programs in switchgrass. One hundred random surviving plants were selected from 5-yr-old plots of six cultivars grown at five locations. Progeny of each population were grown in a four-location field experiment in Illinois and Wisconsin in direct comparison to their parent populations. On average, natural selection for survivorship increased biomass yield by 6.7%. The northernmost (i.e., coldest) selection location had the greatest response among the five locations (13.2%) while the most genetically diverse cultivar had the greatest response among the cultivars (23.5%). Results were highly variable among cultivars and selection locations, but there were no significant negative responses, suggesting that the genetic correlation between survivorship and biomass yield in switchgrass ranges from zero to some positive value. Selection for survivorship within switchgrass sward plots has the potential to improve efficiency of family-based selection methods designed to improve biomass yieldpotential. [ABSTRACT FROM AUTHOR]

This article discusses the lesson learned from an Extension, state, and federal agency coordinated water quality project that was formally started in 1995. In the project, educational programing was provided, high risk areas were identified, and BMPs were implemented on these areas. The net result of BMP implementation was a 38% improvement in South Dakota Bad River water quality. This improvement was attributed to Extension and others providing leadership on: 1) the development of local learning communities and 2) identification and implementing BMP's in high risk areas. This work demonstrates that Extension can make a difference. [ABSTRACT FROM AUTHOR]

Brassica cover crops are an option for producers to incorporate into their cropping system to improve soil health and also provide a feed resource for cattle. While brassica cover crops have been widely used for grazing cows, their use as a backgrounding feedstuff is relatively unknown. The objective of this study was to determine the impact of feeding a brassica cover crop mixture during backgrounding on live animal performance and carcass characteristics. A total of 30 Angus-based steers were assigned to one of two dietary treatments during backgrounding 1) ad libitum access to a diet containing freshly cut brassica cover crop forage (CC) containing radish, turnip, rapeseed, rye grass, and a liquid supplement or 2) common Midwestern dry lot growing diet containing silage, soybean meal, grass hay, and a liquid supplement (CON). Steers were assigned to electronic feed bunks (Insentec RIC, Hokofarm Group; Marknesse, the Netherlands) for collection of individual feed intake. Diets were formulated to be nutritionally similar on a dry matter basis. Steers were paired by weight across treatments and pair fed. Dry matter intake (DMI) was calculated daily for steers in the CC treatment and the following day, CON steers were allowed access to an equal amount of dry matter using the Insentec RIC system. Steers were weighed weekly and backgrounded for 44 days before transitioning to a common finishing diet and weighed every 28 days. Steers were harvested at an estimated average backfat thickness of 1 cm. Standard carcass data were measured and strip loins and shoulder clods were collected. Instrumental and subjective color were measured on ground beef for 8 days and instrumental color was measured on strip steaks for 11 days. Treatment did not influence carcass characteristics, average daily gain, and DMI ( P > 0.17). However, CON steers exhibited increased gain to feed ratio ( P = 0.02). Additionally, a treatment by day interaction was observed for ground beef discoloration as the CC treatment displayed increased discoloration on days 4, 6, and 7 of case life ( P < 0.01). These data indicate that brassicas may be utilized in a backgrounding diet without negatively impacting carcass characteristics but may decrease case life of ground beef., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society of Animal Science.)