Fescue Grassland Research Articles

Evaluation of the botanical composition of kikuyu and fescue grasslands associated with white clover during two seasons in the high valleys of Mexico

Objective. To evaluate the botanical composition of grasslands of kikuyu (Cenchrus clandestinus) compared to tall fescue (Lolium arundinaceum cv. Cajun II), each one in association with white clover (Trifolium repens cv. Ladino), in two independent experiments conducted during two seasons, autumn 2018 and winter 2019. Methodology. Two independent experiments under small-scale milk production system (SMPS) were established in the municipality of Aculco, State of Mexico, during autumn 2018 and winter 2019. The botanical composition of grasslands under intensive continuous grazing by breeding cows was evaluated. One grassland planted with tall fescue cv. Cajun II and the other invaded by kikuyu; each grassland was associated with white clover cv. Ladino. The botanical composition of both experiments was analyzed using a complete randomized experimental design. Results. The kikuyu grassland recorded significant differences (p<0.05) with a higher proportion of forage during the winter 2018. Whereas the tall fescue cv. Cajun II grassland recorded a proportion of forage (p<0.05) higher than its proportion of dead tissue during autumn 2019. Study Implications: The study of the botanical composition of mixed grasslands destined for livestock grazing allows to identify, propose and define strategies for forage production facing agroclimatic and management conditions in order to generate a better and higher forage yield. Conclusions: The proportion of kikuyu was higher than that of tall fescue cv. Cajun II during the two seasons and years evaluated. This highlights the adaptability of kikuyu grass under agroecological conditions such as the absence of rains and high temperatures, coupled with the high stocking densities of the milk production systems in the study region.

Mapping shrub cover in grasslands with an object-based approach and investigating the connection to topo-edaphic factors

Shrubs are important for grasslands; however, shrub encroachment has threatened the integrity of grasslands worldwide. Understanding shrub extent and local effects on encroachment can prioritize management. Studies that map low stature shrubs using an object-based approach in large areas of northern grasslands are limited. This study i) locates shrubs with an object-based approach using 30 cm colour-infrared aerial imagery and Support Vector Machine classification; and ii) investigates shrub distribution by topo-edaphic factors in the native fescue grasslands of the West Block in Cypress Hills Interprovincial Park, Saskatchewan, Canada. The overall accuracy of detected shrubs was above 92%. Loam flat regions, North-facing slopes, and areas with 0% to 25% slope rise are connected to high shrub cover and relate to soil moisture. Shrub presence is high closer to watercourse lines and waterbodies, and low closer to wetlands. This research can apply to other shrub encroached areas to facilitate shrub management worldwide.

Refining Robel Pole Applications for Grazed Idaho Fescue Grasslands in the Big Horn Mountains, Wyoming

Administrative oversight of grazing on public land requires efficient and reliable rangeland monitoring. In a portion of the Bighorn National Forest of Wyoming, the US Forest Service uses the modified Robel pole as a monitoring tool to measure residual herbaceous biomass after grazing. Questions about the vegetation standards have persisted for decades. From 2018 to 2020 we quantified relationships between herbaceous biomass and visual obstruction across spatial, temporal, management, and topoedaphic gradients in 11 grazed pastures selected mutually by stakeholders. Initial standards were developed on the basis of 1 yr of research, and state visual obstruction readings (VORs) were correlated with biomass with an R2 = 0.81, yet our research resulted in R2 values of approximately half (ranging from 0.39 to 0.45) with significantly different slopes 2 of 3 yr. Moreover, the intercepts for each year individually, when averaged, or when combined were always greater than the relationship used to develop initial standards, resulting in 140−564 more kg per ha of biomass at the 5-band standard level, or situations where lower band levels (2.5−3.9) would yield similar biomass levels. In addition to VOR and biomass, slope, aspect, plant and ground cover, weather, and livestock management variables were assessed with information theory models for predicting residual biomass. The top model included VOR, slope, exotic grass, and temperature. This suggests that greater knowledge of the site will increase understanding of biomass production on the site and help to mitigate disagreements among stakeholders by tailoring expectations to variable sites. Finally, the higher intercepts in all of our models may explain the persistent skepticism about the application of the original standard and provide the opportunity to refine standards to better match postgrazing monitoring with resource objectives, particularly if functional group dominance on these sites have changed over time.

Plains rough fescue grassland restoration using natural regeneration after pipeline disturbances

Plains rough fescue (Festuca hallii), once a dominant grassland in the Northern Great Plains, has been reduced to a fraction of its original extent by agricultural intensification and energy sector disturbances and has become a threatened community type. Despite thousands of kilometers of pipelines in grasslands, little is documented about long‐term restoration outcomes. This research assessed recovery of rough fescue grassland 6–21 years after pipeline construction with topsoil stripping and natural regeneration relative to undisturbed reference sites in south‐central Canada. Soil properties varied between pipelines and undisturbed prairie, although most were within theoretical values to support plant growth and development. Vegetation cover, species richness and Shannon diversity and evenness did not differ significantly between pipelines and undisturbed prairie. Multivariate analysis (multi‐response permutation procedure) showed plant community composition, and its dominant species differed significantly between pipelines and undisturbed prairie. Bray–Curtis dissimilarity indices showed dominant species and functional species groups on pipelines were more similar to undisturbed prairie than the undesirable species group. Presence of early‐ to late‐successional species and increasing F. hallii with pipeline age indicate restoration was possible with topsoil salvage and replacement, using natural regeneration as a revegetation method, but requires time to develop and restore a typical rough fescue grassland ecosystem.

Comparative patterns of dung beetle (Coleoptera: Scarabaeidae) diversity in native fescue grassland and wooded habitats in the Cypress Hills, Alberta, Canada

Abstract Dung beetles (Coleoptera: Scarabaeidae (Aphodiinae, Scarabaeinae) and some Geotrupidae) provide important ecosystem services on pastures by disrupting and burying deposits of cattle dung. The extent of these services is influenced by the number of individuals and species present, which may differ with habitat type. In the present study, we compared dung beetle assemblages in a mosaic of open grassland and wooded habitats on native fescue pastures in the Cypress Hills of southern Alberta, Canada. Using pitfall traps baited with cattle dung and operated from spring through autumn for two years at each of the two sites, we collected 4944 individuals representing 14 dung beetle species. More individuals and species were recovered in grassland habitat, which was dominated by nonnative species associated with cattle dung. Wooded habitat was dominated by a native species associated with deer dung. Dwellers (species that develop within the dung deposit) comprised 93% of the beetles recovered during the study. Significant variation in annual beetle counts in the two habitats highlights the value of studies conducted over multiple years. These results emphasise the importance of habitat diversity and interspecific habitat preference in structuring dung beetle assemblages on fescue grasslands, which are among the most threatened ecosystems in Canada.

Recovery of plains rough fescue grasslands on reclaimed well sites

Plains rough fescue (Festuca hallii), once dominant in grasslands of the Northern Great Plains, has been reduced to remnants mainly through agricultural and energy sector development. This study assessed the impacts of oil and gas well site disturbances on plains rough fescue grassland to predict successional trends following disturbance. We examined trends in vegetation cover, richness, diversity, and community composition for two construction techniques (topsoil stripping, minimum disturbance), three revegetation methods (agronomic seed mix, native seed mix, natural recovery), and two reclamation scenarios (reclaimed within < 10 yrs; reclaimed within > 10 yrs) relative to adjacent undisturbed prairie (reference sites) over 28 years in 33 grassland sites. Reclamation success was more closely related to methods of construction and revegetation than years since reclamation. Species richness, diversity, both native and non-native species cover, and species composition were similar between undisturbed prairie and areas subject to minimum disturbance and natural recovery. In contrast, undisturbed prairie differed from areas with topsoil stripping and seeding to either agronomic or native species. Plant community composition on minimum disturbance sites with natural recovery was returning to a predisturbed plains rough fescue community within 10 years after reclamation. Impacts of construction method that involved intensive soil handling and seeding with native or non-native seed mixes were disruptive to recovery of fescue grassland. We therefore recommend retaining grassland sod intact through minimum disturbance and utilizing natural recovery as the best option for successful reclamation of native rough fescue grassland after well site disturbance.

Reductions in foliar Hemiptera in portions of a fescue grassland invaded by Smooth Brome (&lt;i&gt;Bromus inermis&lt;/i&gt;)

Fescue grassland in Canadian prairie is characterized by Plains Rough Fescue (Festuca hallii), but the introduced exotic grass, Smooth Brome (Bromus inermis), is expanding therein. Hemiptera play an important role as herbivores in vegetation. In an invaded fescue grassland in Manitoba, 52 plant species had a combined average cover of 216%. Kentucky Bluegrass (Poa pratensis), another exotic grass, was most abundant at 64%, followed by B. inermis at 21% and the native grass F. hallii at 18%. Across 47 random sample points, B. inermis cover ranged from 0% to 180%. At these points, 2445 specimens of Hemiptera were collected by sweep net and divided into 99 morphologically distinct species. Bromus inermis cover had negative correlations with Hemiptera species richness and diversity, but not with abundance and biomass of Hemiptera. However, B. inermis cover was negatively correlated with abundance of two individual species of Hemipteran leafhoppers in the family Cicadellidae: Doratura stylata and Diplocolenus configuratus. Total graminoid cover had no significant correlation with any of the above Hemiptera variables. We conclude that feeding requirements deter some phytophagous Hemiptera from entering sections of fescue grassland invaded by B. inermis. In this way, invasion by B. inermis can be expected to modify ecosystem function by increasing feeding pressure on neighbouring natural vegetation and other introduced species.

Discussion on the Conversion Method of Soil Enzyme Stoichiometry from Different Vegetation Types in Guizhou Grassland, Southwest China

Soil extracellular enzymes play an important role in regulating the circulation and fixation of soil nutrients, and their stoichiometric ratio reflects the demand of microorganisms for nutrients and the supply of nutrients in the environment, so it has been widely concerned. In this study, the soil C-, N- and P-acquiring enzyme activities (β-1, 4-glucosidase, BG; β-1, 4-N-acetylglucosaminidase, NAG; leucine aminopeptidase, LAP; acid phosphatase, AP) in the upper 30 cm of soils were investigated under three vegetation types (white clover grassland, fescue grassland and natural grassland) to explore the optimal enzyme stoichiometric conversion method. The results showed that the data converted from [asin (βG/[βG + AP])] or [asin (βG/[NAG + LAP])] were more suitable to the normal distribution in general. The response of different soil enzyme conversion methods to soil depth was different. The conversion from [asin (βG/[βG + AP])] or [asin(βG/[NAG + LAP])] in 0-20 cm was more suitable to normal distribution, and the transformation of [ln (P/[1 - P])] was more suitable to normal distribution at 20-30cm. The response of different soil enzyme conversion methods to vegetation type was also different. The conversion from [asin (sqrt [βG/(βG + AP)])] or [asin (sqrt [βG/(NAG + LAP)])] was more suitable in fescue grassland, that of [ln (P/[1 - P])] was more suitable in white clover grassland, and that of [βG/AP]) or [βG/(NAG + LAP)] was more suitable in natural grassland.

Emerging conflict between conservation programmes: when a threatened vertebrate facilitates the dispersal of exotic species in a rare plant community

AbstractAs an ever‐increasing variety of conservation programmes are applied in human‐altered environments, there is a growing risk that different conservation actions with conflicting objectives may impede one another. Preventing and resolving the negative impacts of such conflicting conservation programmes could become a key challenge for conservationists. To date, however, the issue of conflicting conservation programmes has been largely overlooked. We explored a potential conflict between the preservation of threatened free‐ranging plains bisonBison bison bisonand the conservation in a National Park of a rare plant community – native rough fescueFestuca halliigrasslands. We investigated the dispersal of exotic seeds by examining 283 samples of bison faeces and the spatial distribution of exotic plant species in relation to bison behaviour. We showed that bison facilitated the long‐distance dispersal of exotic plant species into the park by transporting seeds. Our analysis indicated there was a high probability (&gt;75%) of occurrence of cloverTrifoliumspp. and timothyPhleum pratenseon bison trails across 38% and 27%, respectively, of fescue grassland area. There was also a high probability of occurrence of timothy on bison wallows across 20% of fescue grasslands area. Furthermore, we demonstrated that exotic plant species were most likely to occur within 3 km of potential introduction points, and identified specific grassland patches most at risk of exotic plant species introduction by bison. By revealing the ecological mechanism underlying the emergence of a potential conflict, we were able to delineate spatial variation in the relative threat that bison might pose to the integrity of native fescue plant communities, allowing managers to optimize the allocation of conservation effort. Our study highlights the value of understanding the ecological mechanisms driving conflict between conservation programmes in order to set evidence‐based priorities for guiding future conservation decision‐making.

Vertical size structure is associated with productivity and species diversity in a short‐stature grassland: Evidence for the importance of height variability within herbaceous communities

AbstractQuestionsLocal size structure is frequently measured in plant populations and forested systems due to its association with population‐ and community‐level processes. In contrast, size structure is rarely examined within herbaceous communities despite evidence for size‐dependent processes in these systems, suggesting an important functional vegetation property may be widely overlooked. Here, we test whether vertical size structure (a) varies within a short‐stature grassland, (b) varies along a productivity gradient, and (c) enhances the understanding of a foundational ecological pattern: the diversity–productivity relationship.LocationRough fescue grassland in Alberta, Canada.MethodsWe measured the heights of individuals within 32 plots and used average height, the Gini coefficient, and a two‐parameter Weibull distribution to estimate community‐level vertical size structure. Linear mixed models were used to test whether size structure parameters were significantly associated with productivity, species richness, and species evenness.ResultsVertical size structure varied significantly among local communities, such that some were dominated by short individuals while others were comprised of a more equal number of taller individuals. With increasing productivity, there was an increase in average plant height and a decrease in height inequality. Decreased height inequality was associated with reduced species richness with evidence that loss was not size‐dependent. The inclusion of vertical size structure parameters increased the explained variance of the diversity–productivity relationship by ~35% while also increasing its parsimony.ConclusionsEven within a short‐stature grassland, there is substantial functional variation in vertical size structure. Productivity is strongly associated with size structure patterns, and the inclusion of height inequalities greatly enhances productivity–diversity relationships, likely because they are the product of assembly mechanisms such as size‐asymmetric competition, assemblage‐level thinning, and niche complementarity. Overall, this demonstrates that vertical size structure has been a missing mechanism in most community assembly theories and models and should be included in the future.

Soil physical and chemical properties in response to long-term cattle grazing on sloped rough fescue grassland in the foothills of the Rocky Mountains, Alberta

Soil physical and chemical properties are critical indicators for soil health assessment. It is important to understand how these qualities respond to different grazing intensities at different landscape slope positions. This study evaluated how soil physical and chemical properties respond to cattle grazing intensity and slope position on a rough fescue grassland. Cattle have been grazing at four stocking rates, 0, 1.2, 2.4 and 4.8 animal-unit-months (AUM) ha−1 since 1949 to simulate Control (CK), Light (L), Heavy (H), and Very Heavy (VH) grazing intensities. Surface soil penetration resistance was measured using a portable penetrometer and soil samples were taken from the top and bottom slope positions for each grazing paddock (but only from the top position for CK) in September 2016. Soil texture, aggregate stability, pH, available phosphorus (AP), water-soluble ions concentration and soil cation exchange capacity (CEC) were determined. Bulk density, porosity and hydraulic properties were measured using a HYPROP system. The S-index, the slope at the inflection point on the soil moisture retention curve, was calculated. Soil clay and silt contents were lower in VH than L treatments; total porosity, air capacity, and saturated water content followed the same pattern. However, the opposite was true for sand content, penetration resistance, and bulk density, with differences between the two grazing treatments greater at the top than the bottom slope position. Grazing changed the shape of soil moisture retention curve in both slope positions with the curve steeper in L than H and VH treatments. The S-index and saturated hydraulic conductivity were reduced by grazing but their responses to slope position and its interaction with grazing intensity were not significant. Soil pH, AP, and water-soluble Na+, K+, Mg2+, Ca2+ and SO42− concentration increased with the animal stocking rate while Cl− and CEC were not affected. Similarly, greater increases in soil pH with increased animal stocking rates were observed in the top than bottom position, while AP, Na+, K+, and SO42− increased with animal stocking rate only in the bottom position. Our results indicate that soil physical properties may be more sensitive to grazing at the top than bottom of a slope. Thus, slope should be considered when developing rangeland soil health assessment indices and grazing management strategies.

Soil disturbance changes arbuscular mycorrhizal fungi richness and composition in a fescue grassland in Alberta Canada

Native grasslands are endangered by non-native plant invasion worldwide, including foothills fescue grasslands in North America. Large populations of non-native plant species have established in these disturbed fescue grasslands, forming dense monocultures and spreading into undisturbed areas. Soil disturbance and plant invasion can alter the arbuscular mycorrhizal fungi (AMF) community, an important symbiotic partner of most land plants, which could negatively affect native plant reestablishment. The objective of this study was to assess whether AMF communities on a fescue grassland shifted in response to disturbances by landfill storage and gravel quarrying and with invasion of non-native plant species relative to undisturbed grassland.Soil and root-AMF samples were procured from disturbed and undisturbed areas at three sites. Plant canopy cover and species richness were assessed. Soils were analyzed for pH; electrical conductivity; total nitrogen, carbon and phosphorus; and available nutrients. For relative AMF taxa abundance assessment, NS31 and AMF specific primer AML2 were used to amplify a central fragment of the V3 and V4 region of the 18S rRNA gene. AMF were characterized using 454 pyrosequencing and multiplexed barcoded samples amplified from genomic DNA isolated from roots.There were 92 AMF, including 15 potentially novel taxa detected. AMF communities in disturbed and undisturbed sampling locations were distinct except for one site, and indicator AMF virtual taxa (VT) for undisturbed grassland and disturbed sites were identified. AMF richness was higher in undisturbed (72 VT) than disturbed (64 VT) sites and AMF richness was positively correlated with plant species richness, diversity and native plant cover, and negatively correlated with non-native plant cover. There were 43 AMF VT on undisturbed and disturbed sites, 62% with higher relative abundance on disturbed sites. Site disturbance shifted AMF communities relative to undisturbed native fescue grassland; thus restoration success with native plants might be highly dependent on reintroducing native AMF.

Modeling nitrous oxide emissions from rough fescue grassland soils subjected to long-term grazing of different intensities using the Soil and Water Assessment Tool (SWAT).

Given the rising nitrous oxide (N2O) concentration in the atmosphere, it has become increasingly important to identify hot spots and hot moments of N2O emissions. With field measurements often failing to capture the spatiotemporal dynamics of N2O emissions, estimating them with modeling tools has become an attractive alternative. Therefore, we incorporated several semi-empirical equations to estimate N2O emissions with the Soil and Water Assessment Tool from nitrification and denitrification processes in soil. We then used the model to simulate soil moisture and the N2O flux from grassland soils subjected to long-term grazing (> 60years) at different intensities in Alberta, Canada. Sensitivity analysis showed that parameters controlling the N2O flux from nitrification were most sensitive. On average, the accuracy of N2O emission simulations were found to be satisfactory, as indicated by the selected goodness-of-fit statistics and predictive uncertainty band, while the model simulated the soil moisture with slightly higher accuracy. As expected, emissions were higher from the plots with greater grazing intensity. Scenario analysis showed that the N2O emissions with the recommended fertilizer rate would dominate the emissions from the projected wetter and warmer future. The combined effects of fertilization and wetter and warmer climate scenarios would increase the current N2O emission levels by more than sixfold, which would be comparable to current emission levels from agricultural soils in similar regions.

Tackling rarity and sample bias with large-scale biodiversity monitoring: a case study examining the status, distribution and ecology of the lichen Cladonia rei in Alberta, Canada

AbstractSpecies conservation depends on accurate data, but for many lichens existing collections are geographically biased and contain many taxonomic errors. It is unclear whether ‘non-expert’, systematic monitoring schemes can address these sources of error, particularly for taxonomically challenging lichens (e.g. species requiring chemistry for accurate identification). In this case study we use the Alberta Biodiversity Monitoring Institute (ABMI), a large-scale, systematic, multi-taxon monitoring programme, to better understand the ecology and distribution of a putative rare species, Cladonia rei. Collections of C. rei from Alberta dating from 1947 suggested the species was broadly distributed but rare, with seven accessioned specimens. We used comparative morphology, thin-layer chromatography and habitat modelling to compare historical records against more recent material from ABMI surveys. Contrary to the historical collections, ABMI samples suggest C. rei is almost entirely limited to the dry mixed grassland, northern fescue grassland and aspen parkland natural regions, and that within these ecosystems it is relatively common. The typical ecotype exhibited included a persistent primary thallus, podetia with a persistent basal cortex, and secondary squamules; typically they lacked cups, well-developed apothecia and fumarprotocetraric acid, and ramifications were sparse. Cladonia rei was consistently found in pastures and undisturbed grasslands that hosted relatively rich communities of epigeic lichens, thus it does not appear to act as a pioneer in Alberta or to commonly occupy the anthropogenic niches documented elsewhere. In summary, large-scale, systematic, non-targeted monitoring employing novices redressed issues of sample bias through almost 300 C. rei collections, simultaneously improving the ecological understanding of a putative rare species.

Transplanting Following Non-Native Plant Control in Rocky Mountain Foothills Fescue Grassland Restoration

Disturbed areas within national parks, resulting from historic and current land use activities, can harbor large and diverse populations of non-native plant species. These species must be controlled to prevent their spread and to restore native grassland. Research on alternative revegetation methods is urgently needed since seed based grassland restoration is often unsuccessful. The effectiveness of transplanting to restore foothills fescue grassland following implementation of non-native plant management was investigated at three disturbed sites in Waterton Lakes National Park, Alberta, Canada. Non-native plant abundance was reduced by cutting, glyphosate application, and steaming. Greenhouse grown seedlings of native fescue grassland species (13 forbs, five grasses, two shrubs) were outplanted into plots following management treatments, as three different sizes of container stock. The effects of prior non-native plant management and container size on transplant survival and growth were assessed over two growing seasons. Rhizomatous forbs and bunchgrasses with well-developed root systems had highest survival ( 50% over 14 months). Transplants with 10- to 15-cm rooting depth in cones and root trainers had significantly higher within-year survival than tray transplants with a shallow rooting depth. Transplant survival was improved by glyphosate application to control non-native plants prior to planting. Transplanting was effective for increasing native cover and species richness although high winter mortality reduced this effect. Key species for fescue grassland function were introduced at all sites and persisted for two growing seasons.

Labile soil organic matter in response to long-term cattle grazing on sloped rough fescue grassland in the foothills of the Rocky Mountains, Alberta

Globally, livestock grazing has pronounced effects on soil carbon (C) and nitrogen (N) cycling, but how labile soil organic matter responds to grazing at different slope positions is uncertain. This study investigated how labile soil organic matter responded to cattle stocking rates and slope position on a rough Fescue grassland. Cattle have been grazing at four stocking rates, 0, 1.2, 2.4 and 4.8 animal unit months (AUM) ha−1 since 1949, representing Control (CK), Light, Heavy and Very Heavy grazing intensities, respectively. Soil samples were collected from the bottom and top slope landscape positions for each grazed paddock (but only from the top position for Control) in May and September 2016. Soil samples were analyzed for organic carbon (OC), total nitrogen (TN), active C (permanganate-oxidizable C), microbial respiration C, available N, potentially mineralizable N (PMN), soil protein, water extractable organic carbon (WEOC) and nitrogen (WEN). Most variables responded to cattle stocking rate (P<0.05) and the responses depended on slope position. Specifically, in the bottom position, OC, TN, active C, NH4+-N, soil protein and WEN contents were higher with Light grazing than with Heavy or Very Heavy grazing. In contrast, for the top position, no significant differences were found among the three grazing treatments for OC, active C, NH4+-N and PMN and all variables were lower than with CK except for PMN with Heavy grazing. As expected, soil OC and TN contents were similar between sampling dates in May and September (P>0.05) while active C, NH4+-N, WEOC and WEN contents were higher (P<0.05) in May than September. Our study suggests that grazing may detrimentally affect grassland soil C and N and slope position plays an important role in regulating the response of labile soil organic matter to grazing. Therefore, there is a need for researchers and range managers to consider developing ‘slope-specific’ grazing strategies to optimize grazing effects.

Plant belowground diversity and species segregation by depth in a semi-arid grassland

ABSTRACTUnderstanding the relationships between below- and aboveground plant community diversity and composition is essential for understanding plant–soil linkages and feedbacks. Here we examine the patterns of belowground plant species richness, evenness, community composition, and individual species relative abundance with soil depth in a rough fescue grassland. Plant taxa belowground were identified via next-generation sequencing of the trnL intron. We found weak positive below–aboveground concordance in plant species composition demonstrating a general similarity between aboveground and belowground communities. The positive relationship between below- and aboveground plant species richness was stronger within the A horizon than in the B horizon, indicating that some species avoided rooting more deeply in the soil. For the most common graminoid species at the site, there was no evidence for depth-related rooting preferences for species of Carex (sedges) or Elymus (wheatgrasses), while the dominant native grass Festuca hallii preferentially rooted shallowly while the invasive grass Bromus inermis rooted more deeply. Differential rooting patterns among some of the dominant species suggests some degree of belowground niche differentiation may be important in structuring this plant community.

Trends in Bird Densities at a Remnant Fescue Grassland in Saskatchewan

Populations of grassland birds in North America have declined greatly in the past five decades. Hypothesized drivers of decline include habitat loss, fragmentation, and adverse impacts from human activities. At a remnant fescue grassland in Saskatoon, Saskatchewan numbers of Savannah Sparrow (Passerculus sandwichensis), Western Meadowlark (Sturnella neglecta), Brewer’s Blackbird (Euphagus cyanocephalus), and Vesper Sparrow (Pooecetes gramineus) have been stable. Numbers of clay-colored Sparrow (Spizella pallida) have increased since the 1960s. Sprague’s Pipit (Anthus spragueii), Upland Sandpiper (Bartramia longicauda), and Burrowing Owl (Athene cunicularia) are no longer present. Baird’s Sparrow (Ammodramus bairdii), Bobolink (Dolichonyx oryzivorus), and Horned Lark (Eremophila alpestris) have become irregular visitors. In the past 50 years, 91 species have been observed displaying territorial behaviour, feeding, nesting, or migrating at this remnant native grassland. With encroaching urban development and increased human influence at the prairie and surrounding area, the impacts on the bird communities at the site in the future are unknown.

Glyphosate, steam and cutting for non‐native plant control in Alberta fescue grassland restoration

AbstractQuestionWhat are the effects of cutting, glyphosate application and steam application on abundance and diversity of non‐native grasses and forbs and non‐target native grasses and forbs in restoration of a complex disturbed fescue grassland?LocationWaterton Lakes National Park, Alberta, Canada.MethodsCutting, glyphosate application and steam application treatments were implemented at three disturbed sites in an incomplete block design with a control. Plant communities were evaluated for four growing seasons, one before and three after management treatment implementation.ResultsGlyphosate reduced non‐native grass cover for three growing seasons following application and non‐native forbs for one growing season. Glyphosate led to significant increases in non‐native forb cover, more than double pre‐existing values 2 and 3 yr after application. Native species abundance and diversity were more negatively impacted by glyphosate on sites with higher abundance and diversity prior to management treatments. Low frequency cutting over 2 yr did not consistently control non‐native species, steam reduced non‐native grass cover at the most heavily invaded site.ConclusionsSite‐specific conditions must be considered to develop effective control methods for non‐native species. No treatment effectively re‐established native grassland communities. Glyphosate application reduced non‐native grasses, but not non‐native forbs. When native forbs were abundant prior to management, glyphosate reduced them. Steam may have potential and should be further investigated. This is one of only a few studies to investigate methods to manage multiple non‐native species occurring with native species, rather than management of a single undesirable species, and is the first to assess steam as a management option for native grasslands.

Festuca campestris density and defoliation regulate abundance of the rhizomatous grass Poa pratensis in a fallow field

AbstractInvasion by the rhizomatous grass Kentucky bluegrass (Poa pratensis) is a global phenomenon, including into foothills rough fescue (Festuca campestris) grasslands of southwestern Alberta, Canada. In order to better understand the competitive relationships between these species, we conducted a fallow field study where rough fescue bunchgrass tussocks were transplanted at one of three planting densities (15, 30, or 45 cm spacing), and then subject to various treatments in a factorial design, including one‐time intensive summer defoliation and seeding of bluegrass into adjacent bare soil. Rough fescue plants exhibited marked intraspecific competition, as high planting densities increased tussock mortality, while decreasing plant tiller counts and relative inflorescence production, together with plant and tiller‐specific mass. However, high densities of the bunchgrass also reduced the cover and biomass of encroaching bluegrass, coincidental with reduced resource (soil moisture and light) availability in mid‐summer. Although summer defoliation increased rough fescue tiller counts, this disturbance reduced plant and tiller mass, and also increased Kentucky bluegrass. We conclude that while high densities of nondefoliated stands of rough fescue may increase resistance to bluegrass encroachment, a reduction in either fescue plant density or vigor via defoliation can increase the risk of bluegrass invasion within northern temperate grassland.