Conventional Alfalfa Research Articles

Alfalfa potassium and phosphorus uptake and use efficiencies as impacted by irrigation technology, deficit irrigation, and alfalfa cultivar

AbstractAs competition for limited water resources in the western United States and other arid and semiarid regions intensifies, there is a need to provide alfalfa (Medicago sativa) growers with knowledge of how water‐optimizing practices impact alfalfa nutrient use. The objective of this research was to evaluate how three water management strategies, and their interactions, influence alfalfa K and P concentration, uptake, uptake efficiency, and internal use efficiency. Alfalfa cultivars, deficit irrigation, and irrigation technologies were tested at two sites in Utah during 2020–2021. A single drought‐tolerant (DT) cultivar (‘Ladak II’) was compared to a conventional alfalfa cultivar specific to each location. Four irrigation rates (100%, uniform reductions of 25% and 50%, and a targeted reduction of ∼50%) were nested within five pivot irrigation technologies. Few alfalfa K and P nutrient dynamics responded to the interactions of cultivar and rate or technology. Nutrient responses to the irrigation technologies were strongly associated with the technology effect on alfalfa yield such that uptake efficiency was sometimes greater with low‐elevation sprinkler technologies. The K and P responses to deficit irrigation were most pronounced at the uniform or targeted 50% irrigation rate. Alfalfa cultivar had the least impact on alfalfa K and P dynamics, and the DT cultivar never improved uptake or efficiencies. These results indicate that few adjustments in K and P management may be needed with the three water optimization approaches evaluated in this study. The most notable is that K and P fertilizer input can likely be reduced with severe deficit irrigation.

The effect of replacing conventional alfalfa hay with lower-lignin alfalfa hay on feed intake, nutrient digestibility, and energy utilization in lactating Jersey cows

Lower-lignin (LoL) varieties of alfalfa (Medicago sativa L.) have been developed in recent years and have the potential to positively affect animal performance. The objective of this study was to evaluate the effects of increasing the proportion of LoL alfalfa hay in diets fed to lactating dairy cows. Research plots were planted with a conventional variety of alfalfa (CON; Dairyland Hybriforce 3400) and 2 LoL varieties (genetically engineered lower-lignin alfalfa [LLG], 54HVX42, and breeding-derived lower-lignin alfalfa [LLB], Aflorex HiGest 460). After harvest, the LoL varieties were blended in equal proportions for feeding. A total of 12 multiparous Jersey cows (100 ± 4 DIM) were used in a 3 × 3 Latin square with 3 periods of 28 d. Cows were assigned to 3 diets containing 0% (control diet; CNTRL), 16.1% (low diet; MdLL), and 32.2% (high diet; HiLL) of the diet DM as LoL alfalfa hay, which replaced CON. The CON alfalfa had average CP, NDF, and lignin contents (DM basis) of 20.5 ± 1.15%, 42.1 ± 1.37%, and 6.81 ± 0.57%, respectively, whereas the LoL alfalfa averaged 19.8 ± 0.75%, 39.9 ± 1.56%, and 6.07 ± 0.28%, respectively. No difference was observed in DMI (20.4 ± 0.61 kg/d). No difference in milk yield was observed, averaging 31.0 ± 1.02 kg/d across treatments. Similarly, no difference was observed in ECM yield (averaging 36.2 ± 1.43 kg/d). Feed conversion (ECM/DMI) tended to increase linearly with LoL alfalfa inclusion (1.74 to 1.80 ± 0.03). No difference was observed for milk fat yield and content (1.39 ± 0.075 kg/d and 4.51 ± 0.219%) or milk protein yield and content (1.06 ± 0.041 kg/d and 3.43 ± 0.096%). Total methane production quadratically decreased from CNTRL to MdLL then increased to HiLL (441, 389, 412 ± 18.2 L/d, respectively). No differences were observed on total-tract digestibility of DM (averaging 67.2 ± 0.55%) and NDF (averaging 50.9 ± 1.56%). No difference was observed in the concentration of digestible energy, metabolizable energy, or NEL was observed averaging 2.82 ± 0.021, 2.51 ± 0.027, and 1.72 ± 0.030 Mcal/kg, respectively. Our results suggest that replacing CON alfalfa with LoL alfalfa has no effects on milk production, milk composition, or nutrient digestibility, but may improve feed efficiency.

Evaluation of meadow fescue grass cultivars seeded with alfalfa in New York state

AbstractAlfalfa–grass mixtures sown in the northeastern United States provide high‐quality dairy forage, and meadow fescue (Festuca pratensis Huds.) may improve the quality of these mixtures. Our objectives were to evaluate competitiveness and nutritive value of nine meadow fescue (MF) cultivars in New York State at spring harvest. Three farms, two in central New York State and one in northern New York state, were used. Conventional alfalfa (Medicago sativa L.) was sown (15 lb acre−1) to nine MF cultivars (three tetraploid and six diploid) and one tall fescue Lolium arundinaceum (Schreb.) ‘Darbysh’ cultivar in a randomized complete block design with four field replicates at each field site at three seeding rates (1, 2, and 3 lb acre−1). Grass proportion in mixtures was estimated visually. Grass samples were collected shortly before first harvest and analyzed for neutral detergent fiber, neutral detergent fiber digestibility (NDFD), acid detergent fiber, in vitro digestibility, and crude protein. Most meadow fescue cultivars maintained a grass proportion between 20%–45% across farms and growing seasons when seeded at 1lb acre−1. Seeding rates above 1lb acre−1 resulted in grass proportions above the recommended 20–30% grass proportion rate. Drought in early 2022 resulted in an average drop in grass percentage of 16.9% units for meadow fescue in mixtures, compared to 2021. Nutritive value of cultivars varied among farms and over growing seasons. Meadow fescue cultivars averaged 2.7% units higher NDFD than tall fescue, and cultivars with consistently high NDFD were Hidden Valley, SW Revansch, SW Minto, and Schwetra. Tetraploid cultivars averaged 4.0% units lower NDF compared to diploid cultivars, which is very advantageous for grass in alfalfa–grass mixtures.

Evaluation of Rumen Degradation Kinetics of Low-Lignin Alfalfa 'Hi-Gest® 360' in Saskatchewan Canada.

The objective of this study was to determine rumen degradation kinetics of new low-lignin alfalfa (Medicago sativa L.) cv. Hi-Gest®360 (HiGest) in comparison with conventional alfalfa cv. AC Grazeland (Grazeland) in monoculture and binary mixtures at different maturity stages. Two cultivars of alfalfa (HiGest, and AC Grazeland) and their binary mixtures with hybrid bromegrass (HBG; cv. AC Success), grown in 2019 at two locations (Saskatoon and Lanigan), were cut at three maturity stages of alfalfa (1 = 10% bloom; 2 = 40% bloom; and 3 = 100% bloom). Rumen degradation characteristics, including rapidly degradable fraction (S), potentially degradable fraction (D), undegradable fraction (U), degradation rate (Kd), lag time (T0), and effective degradability (ED) of each component were determined using in situ technique and were analyzed by a first-order kinetic equation described by Ørskov and McDonald with lag time. Generally, in alfalfa monoculture, S or D were decreased and U was increased without affecting Kd and T0, resulting in decreased ED fraction with increasing stage of maturity. In binary mixtures, plant maturity stages have negligible effects on rumen degradation characteristics of CP. HiGest had higher effective degradability of DM (EDDM) as well as of NDF (EDNDF) than Grazeland. In conclusion, HiGest had greater DM and NDF rumen degradation potential relative to Grazeland. HiGest and Grazeland were different in DM and CP degradation patterns, with HiGest having higher EDDM and EDCP than Grazeland.

PSXII-11 Evaluation of Yellow-Flowered Subspecies Falcata Alfalfa to Purple Flowered Medicago Sativa for Northern Plains: Productivity, Nutrient Profile, and in Vitro True dry Matter Digestibility

Abstract The protein content and nitrogen fixation capabilities of alfalfa (Medicago sativa L.) make it valuable in cropland and rangelands. However, the semi-arid Northern Great Plains climate negatively affects stand establishment and persistence. Falcata alfalfa (Medicago sativa subs. Falcata) produces adventitious shoots from roots, improving stress and drought resistance. This study compared production and forage quality for yellow- flowered falcata alfalfa (FAL) to a conventional alfalfa (var. Vernal [MSP]). Plots were established as randomized complete block design with four replications. Each cultivar was seeded in 2019 as a monoculture. In 2020, two harvests were made and sampled. Dry matter yield (DMY) and nutritive value of alfalfa were determined. Results showed first cut DMY was 4,228±361 and 3,442±720 kg/ha for the FAL and MSP, respectively. Results for forage quality for first harvest indicate that FAL alfalfa had greater (P < 0.05) ash (10.36 vs. 9.85 %), lignin (7. 86 vs. 7. 14 %), acid detergent fiber (ADF: 38.4 vs. 33.4%), neutral detergent fiber (NDF: 45.4 vs. 39.0 %) but less crude protein (CP; 18.7 vs. 21.2 %, DM basis), total digestible nutrients (TDN: 59.2 vs. 55.5%), non- fiber carbohydrates (NFC; 186 vs. 164), sugar (8.4 vs. 7.0 %), in vitro true dry matter digestibility after a 48-h incubation (IVTDMD48: 58.6 vs. 55.8%), compared with FAL. However, for the second harvest, DMY was 2,837±361 kg/ha for FAL, which had greater CP (20.4 vs. 19.4%), similar ADF (35.4 vs. 35.0), NDF (42.7 vs. 41.8 %), and IVTDMD48 (65.6 vs. 64.0%), but lower lignin (7.68 vs. 7.84%) and TDN (58.1 vs 58.9%) than MSP which yielded 2546 ±515 kg/ha. Falcata had greater nutritive value at second cutting and greater yield compared with Medicago but generally differed little for quality, suggesting falcata can be a viable alternative legume for Northern Plains.

Harvesting schedule effects on forage yield and nutritive values in low-lignin alfalfa.

Under the four-cut system, low-lignin alfalfa (Medicago sativa L.) may extend harvesting intervals improving harvest management flexibility and producing forage products with higher nutritive values. The objective of this study was to compare forage yield and nutritive values of low-lignin and conventional alfalfa varieties when applied to six different harvest schedules in the first (2016) and second (2017) production years. There were 12 treatments of two alfalfa varieties as whole plots and six harvest schedules as subplots. Across harvest schedules, there were four cuttings in two production years. Three harvest intervals including “Standard” (high quality, HQ), “Standard+5-day” (medium quality, MQ), and “Standard+10-day” (high yield, HY) were chosen for the first cutting, and 30-day (HQ) and 35-day (HY) for the second cuttings. The third and fourth cuttings in 2016 were timed near final harvest date and in 2017 occurred at 35-day (MQ) and 40-day (HY). Variety by harvest schedule interaction was not significant, but the whole plot and sub-plot effects were significant. Hi-Gest 360 was consistently higher in nutritive value and with a similar yield as Gunner. Harvest schedules did not consistently differ in forage yield and nutritive values. HS-1 (“Standard” + 35-day + Medium Quality + High Yield) with shorter first two cutting intervals provided lower acid detergent fiber (ADF), neutral detergent fiber (NDF), higher relative feed value (RFV), and similar forage yield compared to other schedules. HS-1 had the highest economic incomes when considering RFV and yield among the six different harvest schedules.

PSXI-15 Evaluation of low-lignin alfalfa ‘Hi-Gest® 360’ on the Canadian prairies: productivity, nutrient profile, and rumen degradation kinetics

Abstract The study was conducted at Saskatoon, SK, Canada in the Dark Brown soil zone (52°07′N,106°38′W), to compare low-lignin Hi-Gest®360 alfalfa (Hi-Gest; Medicago sativa L.) to a conventional alfalfa (AC Grazeland) under two cutting regimes. Each cultivar was seeded in 2017 as both a monoculture and binary mixture (binary; Hi-Gest+HB and Grazeland+HB) with AC Success hybrid bromegrass (HB). Plot size was 1.2m×6m with 4 rows. Three years (2018–2020) result suggested that the first cut DMY was 1695±241 and 2151±276 kg/ha for the Hi-Gest and Grazeland, respectively. Hi-Gest had greater (P < 0.05) TDN (68.4 vs. 66.6%, DM basis), NEm (1.7 vs. 1.6 Mcal/kg), IVNDFD48: (42.9 vs. 37.8%), but lower second cut DMY (1288 vs. 1560 kg/ha), ADF (26.3 vs. 28.7%), NDF (34.7 vs. 36.6%), compared to AC Grazeland. Under two cutting, Hi-Gest was numerically lower in total DMY (2983 vs. 3712 kg/ha; P = 0.114) relative to Grazeland. In first cut forage, Hi-Gest also was numerically lower in ADL (5.9 vs. 6.5%; P = 0.57) relative to AC Grazeland. Hi-Gest was similar (P = 0.15) with AC Grazeland in effectively degradable dry matter (EDDM; 622 g/kg DM), effectively degradable CP (EDCP; 689 g/kg CP). Hi-Gest alfalfa had greater (P = 0.05) effectively degradable neutral detergent fiber (EDNDF; 19% more; 340 vs. 285 g/kg NDF) relative to AC Grazeland alfalfa. In binary system, Hi-Gest+HB had (P = 0.02) greater EDCP (12% more; 526 vs. 468 g/kg CP), and numerically greater EDNDF (4.4% more; 259 vs. 248 g/kg NDF; P = 0.10) but had similar EDDM (409 g/kg DM) relative to Grazeland+HB mixture. Each percentage unit increase in alfalfa ADL concentration decreased EDNDF by 2.3 percentage units (EDNDF, % NDF = 46.0–2.93×ADL, % DM, r2=0.26, P < 0.01). Although Hi-Gest yielded less (~25% less) than AC Grazeland, Hi-Gest had greater nutritive value compared to AC Grazeland; differed little for yield and quality in binary mixture, suggesting Hi-Gest can be a viable alternative legume for western Canadian prairies.

Effect of a fall cut on dry matter yield, nutritive value, and stand persistence of alfalfa.

Information is lacking about the effect of date of a fall cut of alfalfa (Medicago sativa L.) on dry matter yield (DMY), forage nutritive value, and stands persistence. The objective of this study was to determine the effect of timing of a fall cut on DMY, forage nutritive value and stand persistence of three alfalfa varieties: low-lignin Hi–Gest 360, Roundup Ready Tonica, and conventional Gunner in Northeastern Kansas in the United States. The field study was carried out by splitting plot in randomized complete block design with four replications. The harvesting data of different maturity stages were collected in each year from 2015 to 2018. Three cuts were harvested based on the stage of maturity, and the last (fourth) cut was done on September 15, September 30, October 15, and October 30 of each year. The persistence of the alfalfa stands was determined each fall after the last cut, and each spring after the first cut, by counting the number of live plants in a randomly placed quadrat in each plot. Alfalfa cut on September 15 and September 30 had a higher stand persistence compared to alfalfa cut on October 15 and October 30. The DMY of the first cut in 2016 was significantly higher in roundup ready than the low-lignin alfalfa variety. In the second cut, DMY was significantly higher in conventional alfalfa than the roundup ready. There were no significant differences in DMY between alfalfa varieties in the rest of seasonal cuttings in 2016 and 2017 and annual total yield in both years. In general, low lignin alfalfa variety had higher crude protein and relative feed value and lower acid detergent fiber and neutral detergent fiber contents than those in roundup ready and conventional alfalfa varieties. On average, nutritive value of alfalfa was generally affected by last cutting dates in 2017. Based on 3-year data the last cutting of alfalfa in the fall could be done by September 30–October 15 without harmful effect on DMY.

Gene flow in commercial alfalfa (Medicago sativa subsp. sativa L.) seed production fields: Distance is the primary but not the sole influence on adventitious presence.

In insect-pollinated crops, gene flow is affected by numerous factors including crop characteristics, mating system, life history, pollinators, and planting management practices. Previous studies have concentrated on the impact of distance between genetically engineered (GE) and conventional fields on adventitious presence (AP) which represents the unwanted presence of a GE gene. Variables other than distance, however, may affect AP. In addition, some AP is often present in the parent seed lots used to establish conventional fields. To identify variables that influence the proportion of AP in conventional alfalfa fields, we performed variable selection regression analyses. Analyses based on a sample-level and a field-level analysis gave similar, though not identical results. For the sample-level model, distance from the GE field explained 66% of the variance in AP, confirming its importance in affecting AP. The area of GE fields within the pollinator foraging range explained an additional 30% of the variation in AP in the model. The density of alfalfa leafcutting bee domiciles influenced AP in both models. To minimize AP in conventional alfalfa seed fields, management practices should focus on optimizing isolation distances while also considering the size of the GE pollen pool within the pollinator foraging range, and the foraging behavior of pollinators.

Effects of alfalfa and alfalfa-grass mixtures with nitrogen fertilization on dry matter yield and forage nutritive value

Alfalfa (Medicago sativa L.) is an important forage legume grown in Kansas, USA and its productivity with cool-season grasses however is unknown. The objective of this study was to determine the dry matter yield (DMY) and forage nutritive value of alfalfa-grass mixtures compared to those of alfalfa and grasses grown in monoculture with and without nitrogen fertilization. Three different alfalfa varieties were planted (reduced-lignin alfalfa, Roundup Ready, and conventional alfalfa) and two kinds of cool-season grasses (smooth brome, Bromus inermis Leyss, and tall fescue, Festuca arundinacea Schreb) were planted as a monoculture or in alfalfa-grass mixtures. Nitrogen fertilizer (urea) was applied at green-up at a rate of 56 kg/ha and after the second cutting at a rate of 56 kg/ha in 2016 and 2017, respectively. and control treatments received no nitrogen. DMY was significantly higher in monoculture alfalfa and alfalfa-grass mixtures than in grass monocultures. Between alfalfa monoculture and alfalfa-grass mixtures, no significant differences in DMY were found. For all treatments, nitrogen application significantly increased DMY compared to the control. In 2016 and 2017, the low-lignin alfalfa monoculture had the lowest acid detergent fiber (ADF) and the grass monocultures had the highest ADF. In 2016 and 2017, neutral detergent fiber (NDF) in smooth bromegrass and tall fescue was higher than in other species treatments. A low-lignin alfalfa monoculture had significantly lower NDF concentration compared to alfalfa-grass mixtures. When averaged over 2016 and 2017, relative feed value (RFV) was highest in low-lignin alfalfa and lowest in the grass monocultures. In both years, nitrogen fertilizer application did not affect nutritive values.

Comparison of plant feedstocks and methods to recover leaf proteins from wet fractionation of alfalfa for potential use in aquaculture, poultry, and livestock feeds

AbstractAlternative plant‐based protein sources are needed for supplementing or replacing fishmeal in formulated animal feeds. Alfalfa (Medicago sativa L.), a perennial legume, is grown worldwide as a high‐protein forage crop used primarily for dairy and beef cattle feeds. However, its utility as a protein source for feeding other farmed animals has great potential. Wet fractionation can provide several products that increase the value of the crop. The amount of alfalfa protein concentrate (APC) recovered from a fresh press filtrate was measured from several feedstocks: herbage of a nonlodging biomass‐type alfalfa, genetically modified reduced‐lignin alfalfa, and conventional alfalfa as well as from leaves of the biomass type fractionated at harvest. Additionally, five methods for APC recovery were compared. Approximately 854 kg of APC, 7,109 kg of press residue suitable as low quality animal feed, and 4.5 Tg of dry hay could be produced annually from a hectare of biomass‐type alfalfa. The amounts of APC recovered from a reduced‐lignin alfalfa and a conventional cultivar were similar. Acid‐based precipitation methods resulted in the largest recovery of APC, whereas heating produced the highest concentration of protein in the concentrate and highest concentration of methionine, lysine, and threonine. The percentage of fatty acids and sugars in the concentrate varied significantly by precipitation method. All methods resulted in low amounts of fiber in the concentrate. Our results indicate that a nonlodging biomass‐type alfalfa can produce high yields of APC and co‐products with fewer harvests than a conventional cultivar, which reduces costs and promotes crop productivity.

Evaluation of the summer slump application of saflufenacil on nondormant conventional alfalfa

AbstractAlfalfa (Medicago sativa L.) is an important crop for the low desert region of southwestern United States. A field study was conducted to evaluate tolerance of established nondormant conventional alfalfa to saflufenacil applied during the summer slump. Treatments consisted of saflufenacil applied alone at 0.7 or 1.4 oz ac−1, or saflufenacil at 0.7 oz ac−1 tank‐mixed with imazamox, bromoxynil, or metribuzin at 0.8, 6.0, or 16.0 oz ac−1, respectively. Methylated seed oil (as surfactant) and ammonium sulfate (as adjuvant) were tank‐mixed at 1 and 2.5% (v/v), respectively, to each herbicide treatment. At 2 d after treatment, alfalfa injury from saflufenacil at the lower rate was lowest (21%); whereas the injury was highest (48%) from saflufenacil plus bromoxynil treatment. The alfalfa injury progressed for 2 wk after treatment (WAT) and was >36% for all treatments except for saflufenacil at the lower rate. Crop recovery was observed about 2 WAT and minimal injury (<3%) occurred at 4 WAT. Alfalfa height was similar across herbicide treatments and the weed‐free (non‐treated) control. At 4 WAT, average alfalfa height for all treatments was 11 inches or greater. The alfalfa injury observed during the initial weeks did not translate into biomass yield reduction. Accordingly, there was no significant difference in alfalfa biomass yield among the treatments. Overall, alfalfa biomass yield was 0.57 and 0.47 ton ac−1 or greater at 4 WAT (1st cutting) and 8 WAT (2nd cutting), respectively, after herbicide application. Our results illustrate that saflufenacil and its tank‐mix with imazamox, bromoxynil, or metribuzin caused injury to nondormant conventional alfalfa during early weeks, but alfalfa recovered by 2 wk after herbicide application without height and biomass yield reduction.

Meadow fescue seeding rate impacts mixtures with alfalfa on marginal sites

AbstractAlfalfa (Medicago sativa L.)–grass mixtures are often used to provide high‐quality dairy forage in the northeastern United States. Meadow fescue (Festuca pratensis Huds.) is popular as a companion for alfalfa in the region because of its high nutritive value. We aimed to evaluate alfalfa–meadow fescue mixtures in northern environments that are unsuited to alfalfa production. Our study was conducted in the year after seeding at two northern New York sites. A reduced‐lignin [fall dormancy (FD) = 4] and a conventional alfalfa (FD = 3) were seeded with diploid and tetraploid meadow fescue varieties in replicated plots, with five seeding rates for meadow fescue. Dry matter yield increased linearly with increased meadow fescue seeding rate. The meadow fescue percentage of mixtures had a curvilinear response to meadow fescue seeding rate, increasing from 44% at the 0.5 lb acre–1 seeding rate to 67.4% at the 4 lb acre–1 rate. Tetraploid meadow fescue had a smaller grass percentage in mixtures and higher nutritive value than a diploid meadow fescue. Reduced‐lignin alfalfa was not greatly different in nutritive value from a conventional cultivar under unfavorable environmental conditions for alfalfa production. We conclude that meadow fescue should be seeded at a very low rate (1 lb acre–1) with alfalfa in northern environments that are unsuitable for alfalfa. Moreover, reduced‐lignin alfalfa (FD = 4) may not result in large increases in nutritive value compared with conventional cultivars selected for high nutritive value on marginal northern sites better suited to FD 3 cultivars.

Effect of Alfalfa Cultivar and Bale Wrap Type on Dry Matter and Forage Quality of Large Round Bales in Outdoor Storage

HighlightsTime to bind a round bale was longest for twine (56 s) compared to B-Wrap® (28 s) and net wrap (18 s).Alfalfa cultivar had minimal effects on changes in dry matter and forage quality of round bales stored outdoors.Dry matter losses were 7% for twine bales, 5% for net wrap bales, while B-Wrap® bales maintained DM in outdoor storage.Deleterious changes in forage quality were generally observed after =180 days of outdoor storage. Abstract. Large round bales are commonly fed to livestock; however, it has been well documented that outdoor storage can negatively impact dry matter (DM) and forage quality. To reduce storage losses and improve feeding value, new wrap types and alfalfa cultivars have been developed; however, these options have not been extensively investigated. Therefore, the objectives of this research were to evaluate the time required to bind large round bales, determine changes in DM and forage quality, and examine the economics of reduced-lignin and conventional alfalfa hay bound in twine, net wrap, and B-Wrap® while in outdoor storage. Hay was baled into 24 large round bales; 12 bales each of reduced-lignin and conventional alfalfa. Within each cultivar, four replicates were bound with each wrap type. Using stopwatches, the time to bind each bale was recorded. At the time of harvest, and every 90±3 days for 365 days, individual bales were weighed and cored to determine changes in DM and forage quality. Significance was set at P = 0.05. Time to bind a bale was longest for twine, intermediate for B-Wrap®, and shortest for net wrap (P < 0.01). Alfalfa cultivar had minimal effects on the parameters measured; therefore, the interaction between wrap type and storage length was reported. After 365 days in outdoor storage, DM losses were 7% for twine bales, 5% for net wrap bales, while B-Wrap® bales maintained DM. Changes in forage quality were observed at =180 days of storage where nonstructural carbohydrates were decreased and insoluble fiber components were concentrated. B-Wrap® bales had a higher value compared to net wrap and twines bales at 180 and 270 days in storage. These results suggest that B-Wrap® was better able to shed precipitation which preserved forage quality and bale value compared to large round bales bound in net wrap and twine in long term, outdoor storage. Keywords: B-Wrap®, Bale value, Net wrap, Reduced-lignin alfalfa, Twine.

The Effects of Feeding Reduced-Lignin Alfalfa on Growing Beef Cattle Performance: a Preliminary Study

Gene suppression techniques down-regulating specific lignin biosynthesis pathway enzymes have permitted the development of an alfalfa variety with an altered lignin content and composition known as HarvXtra. This study was designed to compare the difference in forage nutrient quality between reduced-lignin alfalfa hay (variety HX-4114) and conventional alfalfa hay (variety WL336HQRR), and to evaluate Angus heifer performance when fed treatments of HX-4114 and WL336HQRR. Twenty-four Angus heifers (8 months of age; initial BW = 270 ± 21 kg) were selected to participate in an 84-day alfalfa hay feeding trial. Their performance was evaluated based on changes in body weight (BW), average daily gain (ADG), dry matter intake (DMI), and gain to feed ratio (G:F). Additionally, in situ dry matter disappearance was tested using four ruminally cannulated Hereford cows. Hay samples were collected and used to determine forage nutrient quality, leaf count, and leaf-to-stem ratio. Significance was set at P ≤ 0.05. There were no differences (P ³ 0.05) in forage nutrient quality between alfalfa treatments. Means did not differ by treatment for leaf count (P = 0.06), but leaf-to-stem ratio was higher (P = 0.04) for HX-4114 than WL336HQRR (1.67 vs. 1.17, respectively). There were no treatment or treatment by day interactions for BW, ADG, DMI, G:F, or in situ dry matter disappearance. Additionally, animal performance did not differ for growing Angus heifers consuming HX-4114 and WL336HQRR alfalfa hay. More research is warranted to determine the value of utilizing different genotypes of reduced-lignin alfalfa and their impact on the U.S beef industry.

Practices that Support Coexistence: A Survey of Alfalfa Growers

Core Ideas Genetically engineered alfalfa adoption is higher in areas where alfalfa is not exported. Most respondents practice coexistence strategies, but only 4% test hay seed prior to planting. No respondents in Washington reported testing seed, despite reporting the highest level of export. Growers underestimate the risk of seed spillage during planting and seed harvest and transport. Hay and seed growers need education about transgene dispersal risk and coexistence practices. The alfalfa industry has worked hard to foster the coexistence of genetically engineered and conventional alfalfa production by developing a set of best management practices that aim to limit adventitious presence (AP) of genetically engineered traits in conventional seed. The general goal is to minimize transgene movement by controlling inadvertent admixture (in this case admixture refers to genetically engineered material in conventional seed lot) or gene flow using practices that ensure seed is pure, sanitation is prioritized (i.e., avoidance of seed mixing), spillage is minimized, and pollination is prevented. However, the success of coexistence is dependent on grower adoption, which has not been monitored. To assess adoption we surveyed 530 alfalfa hay and seed producers in three major alfalfa production areas in the western United States in 2013. Based on a 33% response rate, we found that although many respondents reported practices that supported coexistence, the survey identified differences in grower perception and practices in the three states surveyed and identified perceptions and practices that may undermine coexistence. We found that very few respondents (4%) tested hay seed prior to planting, and no respondents in Washington reported testing seed despite reporting the highest level of export. Growers also underestimated the risk of seed spillage during planting and seed harvest and transport. Most respondents controlled feral plants, but control was limited to their own property. Some respondents were using glyphosate to control volunteers and roadside plants. Management of hay fields also varied in terms of cutting time, frequency of delayed cutting, and occurrence of field obstructions that prevented cutting. Our survey suggested that grower education would benefit coexistence, as would research to better understand the potential of genetically engineered hay fields to contribute to economically adverse AP.

A comparison of reduced lignin and conventional alfalfa varieties and their potential for use as equine forage sources

A comparison of reduced lignin and conventional alfalfa varieties and their potential for use as equine forage sources

Migratory Bee Hive Transportation Contributes Insignificantly to Transgenic Pollen Movement Between Spatially Isolated Alfalfa Seed Fields.

Contracted commercial beekeeping operations provide an essential pollination service to many agricultural systems worldwide. Increased use of genetically engineered crops in agriculture has raised concerns over pollinator-mediated gene flow between transgenic and conventional agricultural varieties. This study evaluated whether contracted migratory beekeeping practices influence transgenic pollen flow among spatially isolated alfalfa fields. Twelve honey bee (Apis mellifera L.) colonies were permitted to forage on transgenic alfalfa blossoms for 1 wk in Touchet, WA. The hives were then transported 112 km to caged conventional alfalfa plots following one and two nights of isolation (8 and 32 h, respectively) from the transgenic source. Alfalfa seed harvested from the conventional plots was assessed for the presence of the transgene using a new seedling germination assay. We found that 8 h of isolation from a transgenic alfalfa source virtually eliminated the incidence of cross-pollination between the two varieties.

Field-scale habitat complexity enhances avian conservation and avian-mediated pest-control services in an intensive agricultural crop

The relationship between on-farm avian conservation measures and the potential provisioning of pest-control services by birds is poorly understood in intensive agricultural landscapes, especially in temperate regions. We used an exclusion experiment to test the effects of field- and landscape-scale habitat complexity on avian-provisioned pest-control services and assessed avian abundance and diversity across 32 conventional alfalfa (Medicago sativa) fields in winter and early spring in California. Alfalfa is a key forage crop around the world and is grown on approximately 30 million hectares globally each year. Bird foraging reduced the abundance of the most significant insect pests of alfalfa by over 33%. The presence of complex edge habitat (presence of at least two trees >1.5m) led to higher avian abundance within fields, which in turn led to reduced pest insect populations at sampling points close to the field edge. Fields with complex edge habitat also harbored nearly three times as many bird species as those with simple edge habitat. The distance from the nearest riparian habitat, a measure of landscape diversity, did not affect bird abundance or diversity in winter alfalfa fields, which may be related to the homogenous landscape in which our study was based. Our results show that relatively simple conservation measures in intensively managed farming landscapes, such as planting small trees along a field edge, can result in increased abundance and diversity of over-wintering birds, with direct benefits to farmers through increased avian-mediated pest-control services.

A comparison of ground beetle assemblages (Coleoptera: Carabidae) in conventionally and ecologically managed alfalfa fields

From 2007-2011, the occurrence of ground beetles (<em>Coleoptera</em>: <em>Carabidae</em>) was studied using emergence traps in two differently managed alfalfa fields in the Czech Republic - a conventional and an ecological production system. In total, 784 specimens of ground beetles representing 58 species were trapped in these two alfalfa fields in South Moravia. A slightly higher number of specimens were trapped in the conventionally managed than in the ecological alfalfa stand (404 <em>vs</em> 380, respectively). In the conventionally managed alfalfa stand, the number of species was also higher than in the ecological stand (45 <em>vs</em> 40, respectively). With the exception of 2007 and 2009, Simpson’s indices of diversity were higher in the conventional stand than in the ecological in all study years. Shannon’s index was higher in the conventional alfalfa field in 2008, 2009, and 2011. Regarding distribution, species classified into group E (<em>i.e.</em>, those without special demands on the type and quality of their habitat) dominated in both types of management throughout the experimental period. The incidence of species classified into group R (<em>i.e</em>., those with narrow ecological amplitude) was very low;<em> i.e</em>., only four species. These ground beetle species are included in the Red List of Threatened Species of the Czech Republic, and all of them (<em>i.e</em>. <em>Acupalpus</em> <em>suturalis</em>, <em>Calosoma</em> <em>auropunctatum</em>, <em>Cicindela</em> <em>germanica</em> and <em>Ophonus</em> <em>cribricollis</em>) are listed as vulnerable.