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Livestock grazing supports a considerable amount of economic activity across the United States. Federal grazing permits support numerous ranching operations by providing relatively low-cost grazing on federal lands. While grazing supports employment, labor income, and economic activity within a given state, the extent to which federal grazing permits play a role remains uncertain. In this paper we develop a method for estimating state-level economic contributions of livestock grazing for cattle grazing, as well as sheep and goat grazing, that is applicable to both the US Forest Service and Bureau of Land Management. We report state-level direct response coefficients, defined as the economic effects per 1 000 animal unit months of grazing use. We apply our coefficients to grazing lands for both US Forest Service and the Bureau of Land Management to estimate state-level economic contributions of federal grazing, finding that the economic effects of federal grazing are highest in western states where there are large amounts of public land. The measures of economic impact produced in this study were developed for consistent nationwide analyses. These measures may be used by researchers and land managers for conducting policy impacts and analysis of livestock grazing (e.g., increases or decreases of permitted grazing on public land) but are not intended to replace project- or site-specific economic analyses.
Managing woody species that have encroached into grasslands and can resprout following top-kill has become an increasing problem. Treatments that yield complete mortality (i.e., “root-kill”) such as mechanical grubbing are often too costly at landscape scale. Less expensive treatments that only top-kill are problematic if treatments are not applied frequently to maintain regrowth suppression. More sustainable strategies are needed. Previous research found that a low rate (0.28 kg·ha-1) of clopyralid-only herbicide root-killed some honey mesquite (Prosopis glandulosa) but importantly caused partial top-kill (PTK) in surviving trees that maintained apical dominance and prevented basal sprouting. This management approach, referred to as “vertical brush sculpting,” increased herbaceous productivity compared with top-killed mesquite with dense resprouting. Here we determined if higher rates of clopyralid could increase mesquite root-kill and maintain the PTK physiognomy in surviving plants. We evaluated effects of clopyralid at 0.28, 0.42, and 0.56 kg·ha-1 (C28, C42, and C56, respectively) and a mixture of clopyralid (0.28 kg·ha-1) + triclopyr (0.28 kg·ha-1) (C + T) on mesquite physiognomy. Averaged over two sites at 6 yr post treatment (YPT), root-kill was 0%, 20.0%, 42.8%, 58.9%, and 65.6% in untreated, C28, C42, C56, and C + T, respectively. Among surviving trees, percent PTK with no basal sprouts was greatest in clopyralid-only treatments; percent top-killed with basal sprouting was greatest in C + T. Grass production, measured in untreated, C28, and C + T, ranged from 110% to 215% greater in treated than untreated at 2 YPT. We developed a model to project stand-level mesquite competitive impact on grasses in all treatments over 30 yr. Mesquite competitive impact values were lowest in C42 and C56 due to high root-kill, and most survivors had noncompetitive PTK physiognomy. We viewed C42 as the best option due to lower cost. Vertical brush sculpting offers a method to reduce woody competition with grasses yet maintain landscape heterogeneity.
Mitch G. Thacker, Matthew D. Madsen, Benjamin W. Hoose, Rhett M. Anderson, David R. Tryon, Randy T. Larsen, Kevin L. Gunnell, Daniel D. Summers, Todd E. Erickson
Ecological restoration of rangelands using wild-collected seeds can be challenging due to low seed quality, inconvenient seed anatomy, and poor plant establishment. In North America, the half-shrub winterfat (Krascheninnikovia lanata) is a valuable protein-rich forage for wildlife and livestock. Seeds of this species are contained in one-seeded fruits enclosed in four fluffy, silky bracts. While the seeds can be removed from the bracts, it is not recommended as the bracts are thought to help protect the seed and aid in germination and seedling growth. However, bracts of winterfat make it difficult to incorporate this species within a seed mix because they prevent the seed from flowing through mechanized seeders. The anatomy of winterfat fruit also makes it difficult to treat this species with external seed-coating materials that may aid in direct seeding efforts. We tested the use of a recently developed flash-flaming technique in combination with seed coating to improve the flowability of winterfat fruits. Our results indicate that flash flaming can reduce the appendages on winterfat fruits, which decreased fruit volume by up to 46% without impacting seed germination. Flash flaming also makes it possible to incorporate a polymer seed coating to the exterior of winterfat fruits. We found that flash flaming combined with seed coating improved the flowability of winterfat fruits, as measured with standard laboratory tests and by delivering fruits through a broadcast seeder and a rangeland drill. These results indicate that flash flaming plus seed coating provides a new technology that will allow for the treating and planting of winterfat on degraded rangelands.
Katherine M. Nigro, Taylar Z. Bankston, Ariel B. Demarest, Alison C. Foster, Angela D. Gonzalez, Edward M. Hill, Andreas P. Wion, Gwen D. Wion, Robert N. Addington, Noah Amme, Tegan M. May, Chris A. Pague, Renee Rondeau, Miranda D. Redmond
Tree-removal treatments have been broadly applied across piñon-juniper ecosystems of the western United States to reduce tree cover, stimulate understory plant production, and promote habitat for shrub- and grassland-obligate wildlife species. Mastication treatments have become an increasingly common approach, yet the efficacy of these treatments can vary on the basis of a variety of factors, including soil characteristics, woodland structure, and grazing pressures. Here, we assessed vegetation responses to mastication treatments across three dominant soil types in two-needle piñon (Pinus edulis Engelm. [Pinaceae])-one-seed juniper (Juniperus monosperma [Engelm.] Sarg.) woodlands in southeast Colorado, United States, a region characterized by monsoonal precipitation, limited presence of introduced plant species, and relatively high grazing intensity by cattle and wildlife. We found that mastication treatments were effective at increasing herbaceous plant cover and species diversity (by 1.2 × and 1.5 ×) and at reducing the amount of exposed soil (60% reduction) 3 yr following treatment. This was mainly due to increases in native perennial grasses. Further, there were limited (and insignificant) increases in cover of annual plants and low abundance of introduced species in treated plots. Understory plant responses to treatment were similar across soils with a range of available water capacities. The increase in understory plant cover and richness paired with the low abundance of introduced species suggests that mastication treatments increase forage production for cattle and wild ungulates. In addition, the lack of soil type differences in treatment response suggests that mastication treatment placement does not need to prioritize soil type and can instead focus on other key areas of importance, such as wildlife habitat connectivity, historic woodland structure, and treatment feasibility.
Populations of mammalian carnivores are growing in the western United States, leading to increases in conflicts with people because carnivores prey on species that are highly valued by humans, such as domestic livestock. Accurate and updated information on the impact of predators on prey is essential when making management decisions and mitigating domestic livestock losses, yet it is difficult to detect mortalities and determine whether depredation has occurred when livestock graze on public allotments. We sought to accurately quantify the effects of predation on domestic lambs when grazing on public allotments. We placed 934 very-high-frequency (VHF) collars on lambs in seven herds that graze on public allotments at two study sites—one in northern and one in central Utah, United States. We then monitored collared lambs daily throughout the summer grazing season (April-September 2021). Of the 934 collared lambs, there were 51 (5%) lamb mortalities, for which 28 were determined to be from predation, 12 from nonpredatory causes, and 11 from unknown causes because they were too decomposed to accurately determine a cause of death. Predators responsible included coyote (Canis latrans), cougar (Puma concolor), and bobcat (Lynx rufus). Overall, few lambs die in their first 3 mo, but of those that died, we found noticeable differences in the causes and number of mortalities among herds but no differences between study sites or in predation rates within herds over time. Our results suggest lamb survival may primarily be a function of animal husbandry practices or specialization by individual predators within a grazing allotment. This study provides insight into what factors influence lamb mortality and highlights areas ranchers and managers might focus on when seeking to increase lamb survival and reduce depredation.
Public rangeland managers face mounting pressure to resolve wild horse (Equus ferus caballus) population growth in the western United States, whose escalated ecological impact has alarmed numerous stakeholders. Unfortunately, long-term solutions have remained elusive as approved control methods, limited in breadth and scope as a result of legislative changes, hamstring managers and provide only limited, short-term reduction potential (e.g., drylot confinement, adoption, short-term fertility treatments). Management flexibility is further constrained due to costs of confinement (> 50% of the Bureau of Land Management's wild horse and burro program budget), constraints on per-person horse adoptions, and labor intensity of fertility treatments given required follow-up vaccination, which all place significant burdens on federal budgets and staff. To better understand the wild horse population problem, a system dynamics model was constructed linking population levels with current and historical control strategies. For the population to reach balance with appropriate management levels (AMLs) and assuming horse harvest bans and confinement capacities do not change, annual adoption rates of ≈15 000 head or annual short-term fertility control of 40% of mature horses would be required for 38–50 yr, while grazing lease buyouts would only alleviate internal pressure on desired removals. Combinations of increased adoptions and fertility controls balanced the population with AMLs between 16 and 38 yr. Should horse harvest bans be lifted and permanent fertility control become feasible, balance with AML could be achieved in 9–25 yr depending on time of implementation and rate of use. Recognizing mental models underlying various policy priorities will help improve coalition building. Finding ways to reward management creativity that accelerates ecosystem health improvement efforts within the various constraints on public agencies and stakeholders will shorten time delays between implementation of long-term resolutions and observing the results of such effort.
Contemporary restoration and management of sagebrush-dominated (Artemisia spp.) ecosystems across the intermountain west of the United States increasingly involves the removal of expanding conifer, particularly juniper (Juniperus spp.) and pinyon pine (Pinus edulis, P. monophylla). The impetus behind much of this management has been the demonstrated population benefits of sagebrush restoration via conifer removal to greater sage-grouse (Centrocercus urophasianus), a species of conservation concern. One of the challenges with scaling up from a focal-species approach to a community-level perspective, however, is balancing the habitat requirements of different species, some of which may overlap with sage-grouse and others which may have competing habitat needs. Here, we use a systematic conservation planning approach to compute spatial optimizations that prioritize areas for conifer removal across the sage-grouse range while incorporating woodland and sagebrush songbirds into decision making. Three of the songbirds considered here, Brewer's sparrow (Spizella breweri), green-tailed towhee (Pipilo chlorurus), and sage thrasher (Poocetes gramineus), are sagebrush-obligates, while another is a woodland-obligate, the pinyon jay (Gymnorhinus cyanocephalus). We find that the inclusion of sagebrush-obligates expands the model-selected area of consideration for conifer management, likely because habitat overlap between sagebrush-obligates is imperfect. The inclusion of pinyon jay, a woodland-obligate, resulted in substantial shifts in the distribution of model-selected priority areas for conifer removal, particularly away from pinyon jay strongholds in Nevada and east-central California. Finally, we compared the conifer optimizations created here with estimates of ongoing conifer removal efforts across the intermountain west and find that a small proportion (13-18%) of management efforts had occurred on areas predicted as being important for pinyon jay, suggesting that much of the ongoing work is already successfully avoiding critical pinyon jay habitat areas.
Reestablishing perennial vegetation dominance in ventenata (Ventenata dubia)– and other annual grass–invaded rangelands is critical to restoring ecological function and increasing ecosystem goods and services. Recovery of perennial dominance in ventenata-invaded rangelands is challenging and constrained by a lack of established best management practices; however, preemergent herbicides can, at least temporarily, reduce ventenata. Indaziflam is a preemergent herbicide that has longer soil activity than other commonly used preemergent herbicides that needs evaluated to determine if it offers multiple-year control of ventenata and to determine its effects on residual perennial vegetation. Some ventenata-invaded rangelands may not have enough residual vegetation to occupy the site after ventenata control, but longer soil activity with indaziflam likely limits establishment of seeded species. However, incorporating seeds in activated carbon pellets, which can limit herbicide damage, may be a strategy for establishing perennial vegetations simultaneously with indaziflam application. We evaluated 1) applying indaziflam to control ventenata and 2) broadcast-seeding perennial grass seed incorporated in activated carbon pellets with a simultaneous indaziflam application at two sites for 3 yr post treatment. Indaziflam controlled ventenata for the 3 yr sampled. Perennial grasses increased with indaziflam at the site that had more residual perennial grasses before treatment. At the other site, perennial forbs increased with indaziflam. Indaziflam offers multiple-year control of ventenata; however, plant community response depends on composition before treatment. Seeding perennial grass seeds incorporated in activated carbon pellets while indaziflam controlled ventenata did not increase perennial grass abundance. Though this was likely associated with low establishment due to below-average precipitation post seeding and because broadcast seeding is often an ineffective seeding method, we cannot rule out nontarget herbicide damage. Further evaluations of activated carbon technologies used in conjunction with indaziflam are needed to determine if this can be an effective management strategy.
Landscapes used for livestock agriculture are common worldwide and have the potential for wildlife-human conflict, particularly when carnivores prey on livestock. Identifying habitat features that influence carnivore movements in livestock areas can help mitigate conflict. The caracal (Caracal caracal) is a common mesopredator on farms in southern Africa. We used Step Selection Functions to identify habitat selection of Global Positioning System collared male caracal (n = 8) along their movement paths on private farmlands in a semiarid region of South Africa. In the wet season, some caracals selected rugged terrain but high elevations were avoided by certain individuals. Electric fences were avoided, whereas some animals moved close to farm buildings. Many caracals selected shrubland and avoided main roads, but the opposite movement choices were documented for some individuals. Plowed fields were consistently avoided. In the dry season, caracal movements were similar to those recorded in the wet season, but there was greater variability in individual choices. On the basis of model averaging, caracals appeared to move closer to electric fences in the dry season, but such patterns were not significant from individual-level analyses. Because some caracals avoided, whereas others selected, the same habitats or anthropogenic features and model averaging could not detect those differences, we recommend that whenever possible, individual movement choices of predators are assessed. For caracals and other carnivores that prey on livestock, understanding the ecology of individuals as opposed to exclusively population-level habitat choices may be more informative for conflict mitigation.
The efficacy of livestock guarding dogs (LGDs; Canis familiaris) on modern ranches in the dense multiuse landscape of rural northern Israel is controversial. Minimal time is spent by the ranchers with the herd and LGDs, and the LGDs are known to wander to nearby army bases, homesteads, villages, and other facilities. Thirteen Akbash and six mixed-breed LGDs guarding cattle in a paddock were observed through direct observations and tracking with Global Positioning System collars. Predator presence and interaction with LGDs were recorded using telemetry and trail cameras. In addition, 10 local ranchers were interviewed to assess the effects of management and LGD use on depredation. We expected Akbash LGDs to exhibit behavioral traits consistent with depredation mitigation and that differing ranch-LGD management methods would impact depredation levels. At the study ranch, depredations were at a minimum despite the presence of three wolf packs (Canis lupus) and jackals (Canis aureus) in the vicinity of the observed ranch. The Akbash LGDs spatially displaced wolves and temporally displaced jackals, but they also regularly roamed away from the paddock and returned. In addition, Akbash LGDs were more likely to follow the herd than mixed-breed LGDs; the total number of LGDs in the paddock increased with the number of newborn calves; and LGD intra-aggression increased with the number of LGDs present in the paddock. In the survey, we found little relationship between ranch management type and depredation outcomes. In particular, the use of protective enclosures by some ranches did not mitigate depredation compared with ranches without enclosures. In modern multiuse landscapes, Akbash LGDs show potential for being an important component of depredation mitigation, but their relative contribution needs to be studied further. In addition, the use of protective enclosures, which are known to have negative ecological impacts, should be reconsidered. Several improvements to LGD management are suggested.
Desert truffles are edible hypogeous fungi, which grow in arid and semiarid areas of the Mediterranean region. They play an important role in the maintenance of rangelands by preventing erosion and desertification. In recent years, rangelands have experienced serious crises due to global warming and groundwater scarcity. One of the ways to improve rangelands is to use desert truffles as part of conservation or restoration efforts. For these reasons it is important to study the mycorrhizal association of these fungi with rangeland plants. For the first time, we investigated the mycorrhizal association of the desert truffle (Tirmania pinoyi) with the perennial plant species Helianthemum lippii, Helianthemum almeriense, Cistus laurifolius, and Cistus ladanifer. We inoculated all four plant species with T. pinoyi and found the presence of an ectendomycorrhizal association with varying degrees of sheath development. Our results shows that H. lippii is a suitable plant host for T. pinoyi, and the mycorrhization rate and relative mycorrhizal dependency in this native plant were about 90% and 57.85%, respectively, and higher than the other three plant species. The effect of the mycorrhizal fungus on host growth (root weight, root height, shoot weight, shoot height, plant height, and plant weight) was statistically significant compared with noninoculated plants. To detect the roots colonized by T. pinoyi, a polymerase chain reaction (PCR)-based diagnostic method was developed with the species-specific primer pairs FTiPi and RTiPi designed from the sequence of the internal transcribed space regions (ITS1 and ITS2). The specificity of the primers was verified by PCR analysis of DNA from T. pinoyi specimens and other desert truffles. The method detected T. pinoyi in inoculated root plants, and no cross-reactions were observed with any other tested desert truffles. This species-specific PCR method is suitable for quick, simple, and reliable detection of T. pinoyi mycorrhizas.
Rangelands in the northern Great Plains are threatened by invasive C3 annual and perennial grasses that displace native C4 grasses. Rehabilitating these rangelands by reintroducing native C4 grass species could extend the season in which relatively higher-quality forage is available for livestock grazing and improve wildlife habitat. Three seeding treatments, four herbicide treatments, and two stocking densities were applied to a pasture in central South Dakota, United States, that was dominated by invasive C3 grasses. Grazing and herbicide treatments were designed to suppress exotic cool season grasses. Drought limited establishment during the first 2 yr, but C3 grasses were successfully controlled during this time. Plots drill-seeded and sprayed with glyphosate established a mean of 1.0 seeded grasses m-2 by the third yr. Unseeded plots and plots that did not receive glyphosate failed. This trend continued into yr 5, when the most successful treatments were composed of 10-14% seeded C4 grasses, as determined by a modified step-point count technique. Stocking density did not affect establishment success. It is possible to suppress C3 invasive grasses with herbicide and establish native C4 tallgrasses in central South Dakota, but drought makes it a risky proposition in this semiarid region.
Eastern redcedar (ERC) (Juniperus virginiana L.) encroachment threatens long-term Great Plains health. Goats browse juniper by defoliation and debarking but are limited by aversive postingestive feedback from plant secondary metabolites. Protein supplementation may increase fed juniper foliage intake by offsetting nitrogen loss from plant secondary metabolites-protein binding, but little is known for goats browsing whole juniper, mimicking a field setting. Therefore, the objective was to study the effects of rumen undegradable protein (RUP) supplementation and tree height on goat browsing. Experimental design was two 3 × 3 Latin squares of two diets and three ERC tree height treatments. Within each square, 12 Savannah × Spanish × Boer crossbred 50 kg ± 3.9 kg does were fixed to a diet for 10 d (7 d adaptation and 3 d ERC browsing). Fed diets were control (grass hay and whole corn) and supplemented (grass hay and dried distiller's grain, an RUP source). Diets were isocaloric, and supplemented diet crude protein was fed at 2 × maintenance. Each pen (three pens of four goats per diet) was offered two trees from one of three tree height treatments for 8 h daily over 3 d in a rotation where pens received all tree height treatments. Supplemented RUP did not increase defoliation (P= 0.73), trunk debarking (P= 0.84), or branch browsing (P= 0.74). However, tree height may impact browsing as short (50 cm) trees were more defoliated and 50 cm and 100 cm trees had more branches browsed than taller (200 cm) trees (P < 0.05). Therefore, for field application relevance, it may be more important for pen studies to measure browsing of whole juniper rather than fed foliage intake. Future pen and/or field studies should explore alternative protein sources, consider tree height in their design, and offer goats whole juniper.
Cattle (Bos taurus) grazing on public lands is widespread across the globe. Public rangelands are managed for multiple purposes, including preservation of wildlife populations; therefore, to manage public rangelands, it is imperative to understand how cattle grazing affects wildlife. Despite this, there is mixed evidence for the impacts of cattle on wildlife and few studies investigate both spatial and temporal aspects of wildlife activity. To improve understanding of how cattle grazing impacts spatiotemporal wildlife activity, we analyzed camera data from three California Department of Fish and Wildlife properties in California, the United States from 2019 to 2021. We recorded 2 863 detections of cattle across all properties and the most abundant wildlife were coyotes (Canis latrans, 572 detections) and mule deer (Odocoileus hemionus; 1 415 detections). We used generalized linear mixed models and daily activity estimates to quantify cattle, coyote, and mule deer spatial and temporal activity and compared activity during grazing and nongrazing periods (properties were grazed 3-6 mo per year) and between sites with higher and lower cattle use. Mule deer spatial activity changed seasonally and at one property decreased during grazing seasons, but there were no overall significant effects of cattle detections on mule deer spatial activity. However, deer were more nocturnal at sites with higher cattle use, indicating that they may have been partitioning areas temporally with cattle. This shift in activity also increased deer overlap with more nocturnal species, like coyotes. Coyotes increased use of sites with higher activity of their prey and increased use of times with higher cattle activity. Our study suggests that low to moderate cattle grazing does not result in significant spatial displacement of common large mammals; however, shifts in temporal activity patterns of wildlife due to cattle presence may impact predator-prey interactions and wildlife energy expenditure and needs further monitoring.
Herbicides have been widely used to manage woody vegetation, but quantification of their effects is often lacking. We documented the impacts of a commonly used clopyralid + aminopyralid + triclopyr herbicide blend on Prosopis velutina Woot. in grazed Sonoran Desert grasslands in southern Arizona. Similar to other applications of comparable herbicide blends in the region, we recorded only modest and short-term impacts. P. velutina mortality was 7%. Foliar cover declined to 9.2% ± 0.80% the month following treatment and was comparable across size classes. Cover reductions persisted for ∼2 yr, by which time it was comparable on treated and control plants (66.9% and 69.3%, respectively). On the basis of eddy covariance tower monitoring of carbon and water flux, soil temperature, and soil moisture, we suggest how knowledge of diurnal and seasonal changes in physiological activity (e.g., evapotranspiration, gross primary production) and environmental conditions may help identify more optimal times to apply herbicides to improve their efficacy. Future research should explore P. velutina response to herbicides at various levels of photosynthetic activity in response to soil temperature and soil moisture in the subtropical North American Monsoon climate system of the Sonoran Desert. From a broader ecosystems trophic perspective, our results also suggest a need to ascertain how herbicide-induced reductions in P. velutina pod and seed production may impact native herbivore communities.
Seasonal precipitation and temperature directly affect total plant production in the California Annual Grassland (CAG). Technological advances have resulted in skillful seasonal climate forecasts (i.e., significant correlations between actual and forecasted climate), which could be input into plant production models to inform stocking and other rangeland management decisions. This study presents a procedure for forecasting plant production in the CAG ecosystem to predict annual plant production for grazing, restoration, or other rangeland management practices using a combination of historical gridMET climate data and seasonal hindcasts (i.e., retrospective forecasts, from the North American Multi-Model Ensemble program). The results of this study first confirmed high forecast skill, throughout the growing season at all sites. We also identified skillful plant production forecasts across most of the growing season at two sites and in three of the seven forecasting months at one study site. Forecasting climate and end-of-year plant production across the growing season at three CAG sites allowed us to identify the places and times in the growing season when forecasting might be most helpful in informing management decisions. Integrating plant production forecasting into rangeland management practices could significantly improve rangeland management outcomes. These procedures provide a user guide for creating plant production forecasts for any given area of interest and may be applicable across a wide range of other agricultural and rangeland management systems.
Restoration of the foundational species, big sagebrush (Artemisia tridentata Nutt.), of the sagebrush steppe biome has not kept pace with the loss of habitat, demanding new tools to improve its restoration. Seed enhancement technology (SET) is one approach that is increasingly being tested in native plant restoration as a means to overcome establishment barriers. Like many semiarid shrubs, sagebrush faces establishment barriers from inadequate moisture, competition from faster-growing grasses, and limited available nutrients. We performed a series of laboratory trials testing whether nutrient amendments could be applied to sagebrush seed using a SET to increase root length and biomass, thereby potentially increasing seedling survival. We initially tested 11 amendments applied directly to bare seeds; of these, a high-phosphorus fertilizer resulted in a 2.7x increase in root biomass and 71-mm increase in root length over the control. We then tested incorporating this fertilizer at multiple concentrations into a pellet SET and a ground dust. Although the fertilizer, particularly at higher concentrations, conferred some enhancement to seedling biomass, the pellet treatments had substantially lower emergence and survival than bare seed and dust treatments. These results indicate the potential for a “root-enhancement” SET to benefit sagebrush and other species like it; they also illustrate some of the challenges of SET development for native species. Sagebrush has small seeds that typically need light to germinate. Further work is needed to develop an appropriate technology that does not negatively impact emergence but still provides enough nutrients for enhanced root growth. Field testing is also needed to determine if increases in root growth translate into greater survival. Given the low success rate of sagebrush seeding in restoration projects, however, we suggest that it is worth considering root-enhancement SET alongside other efforts to improve sagebrush establishment success.
Portions of the western United States, extending from west Texas to eastern Oregon, are thin to densely populated with juniper (Juniperus spp.) woodlands. Managing tree densities, such as through mechanical thinning, has numerous ecological implications for rangeland watersheds and wildlife habitat. The objective of this study was to determine vegetation response to juniper removal in a pinyon (Pinus edulis Engelm)- and juniper (Juniperus monosperma Engelm)- dominated landscape in north-central New Mexico. Herbaceous cover and standing crop were collected from six 1.00- to 1.35-ha catchments situated within the New Mexico State University (NMSU)-Santa Fe Ranch, Santa Fe County, New Mexico, before treatment and at 5 and 10 yr following juniper removal. About 70% of mature juniper trees were cut in 2009 in three of the catchments (treated) while the remaining catchments were left as controls (untreated). Herbaceous cover and standing crop were measured in 2009 (pretreatment), 2014, and 2019 (post treatment) to test our hypothesis that juniper reductions would significantly increase herbaceous standing crop. After 10 yr, gravel, grass, and forb cover were comparable in the treated and the untreated, whereas bare soil cover was significantly decreased in the treated (30% ± 2.5) compared with the untreated (42% ± 2.5). Litter cover in the treated was higher (18% ± 2.6) than the untreated (5% ± 2.6). Herbaceous standing crop significantly increased in the treated compared with the untreated. Standing crop of grass in the treated was two to three times greater than the untreated. Forb standing crop was not influenced by treatment but increased over time in both treatments. Study findings provide land managers with critical information regarding one-seed juniper clearing effects on herbaceous vegetation response in the warm-climate rangeland ecosystems of the southwestern United States.
The species-rich natural and seminatural grasslands of East-Central Europe have long offered diverse forages and fodder species for domestic livestock. The use and perception of forage and fodder plants are influenced by various agricultural, environmental, sociocultural, technical, and political factors. In our paper, we compared four indicator sets used by traditional land users and scientists since the Enlightenment period (18th century) until the present. We analyzed 24 literature sources and field data from Poland, Hungary, and neighboring countries. We found 2 049 records related to 529 plant species and identified 47 different types of forage/fodder quality indicators. The most often used indicators in the Enlightenment science indicator sets were “nutritional value,” “livestock preference,” and “impact on livestock health”; in the early ethnographic indicator sets (late 19th, early 20th century) “impact on livestock health” and “used for curing”; while the modern rangeland indicator set focused on “nutritional value,” “impact on livestock health,” and “productivity” of plants. The indicators used by present-day traditional herders and farmers in Hungary and Romania resembled the indicators documented in the Enlightenment period. We found data for more than 130 plant species on plant-livestock interactions that have the potential to be used in nature conservation management of seminatural pastures and meadows. The data include species currently considered protected, rare, and/or threatened in the studied countries. We argue that plant ecologists, conservation biologists, and practitioners could efficiently use historical and traditional knowledge sources about wild forage and fodder species for better and more sustainable management of species-rich grasslands in Europe.
Grazing land remains the major feed source for livestock for smallholder farmers in Ethiopia; however, its productivity is low and it is prone to degradation. A field experiment was conducted to evaluate the effects of farmyard manure (FYM) and enrichment planting with improved forages on biomass yield, nutritional value, and soil chemical properties in dryland areas of northwestern Ethiopia. The experiment was carried out using a randomized complete block design with three replications for 2 yr. Natural pasture plots were seeded and treated with Napier grass (Pennisetum purpureum) or desho grass (Pennisetum pedicellatum), Napier or desho + FYM, Napier or desho + Desmodium, and Napier or desho + FYM + Desmodium; untreated plots were used as controls. In the yr 2019, after treatment application the overall herbaceous species identified in the experimental plots were grasses (64%), legumes (22%), and forbs (14%). In all treatment groups, legumes dominate in the first yr while grasses dominate in the second yr. Within treatment groups, dry matter yield (DMY) increment was recorded from the first yr to the second yr, by values ranging from 2.9% to 23.0%. The mean DMY in the desho + FYM + Desmodium uncinatum plots (8.4 t ha-1) was higher (P < 0.001) than controls (4.4 t ha-1). Natural pasture treated with Napier or desho in conjunction with either Desmodium or FYM and their combinations had a higher crude protein content (P < 0.001) than natural pasture alone despite the fact that in vitro organic matter digestibility was higher in desho grass when combined with desmodium or FYM treatments. Plots treated with Napier + FYM, Napier + Desmodium, and desho + Desmodium + FYM showed organic carbon levels that were significantly (P < 0.001) higher than the controls. Overall, desho + FYM + Desmodium produced the greatest improvement in grazing land productivity by maintaining soil fertility.
Jason D. Tack, Joseph T. Smith, Kevin E. Doherty, Patrick J. Donnelly, Jeremy D. Maestas, Brady W. Allred, Jason Reinhardt, Scott L. Morford, David E. Naugle
In the western United States, pinyon-juniper woodlands have expanded by as much as sixfold among sagebrush landscapes since the late 19th century, with demonstrated negative impacts to the behavior, demography, and population dynamics of species that rely on intact sagebrush rangelands. Notably, greater sage-grouse (Centrocercus urophasianus) are unable to tolerate even low conifer cover, which can result in population declines and local extirpation, whereas removing expanding conifer cover has been demonstrated to increase sage grouse population growth rates and sagebrush obligate songbird abundance. Yet conifer management among sagebrush landscapes has been met with concerns about unintended impacts to species that rely on conifer woodlands, notably the pinyon jay (Gymnorhinus cyanocephalus), whose population declines are distinctive among birds breeding in pinyon-juniper woodlands. Spatial models of bird abundance can help management prioritize future actions in light of multiple species requirements, while also providing a framework to retroactively test the impact of past treatments. We used Breeding Bird Survey data to model indices to abundance in relation to multiscale habitat features including landcover, fire, topography, and climate variables for nine songbird species reliant on sagebrush and pinyon-juniper woodlands for breeding. Predictive maps allowed us to also examine the overlap of conifer management conducted by the Sage Grouse Initiative (SGI), which targets management of early successional conifers among priority sage-grouse habitats, with predicted indices to abundance of songbirds. Our findings demonstrate that targeted sage grouse habitat restoration under SGI was not at odds with protection of pinyon jay populations. Rather, conifer management has largely occurred among northern sagebrush landscapes where models suggest that past cuts likely benefit Brewer's sparrow and sage thrasher while avoiding pinyon jay habitats.
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