Peggy Ann Desserud

Restoration of foothills rough fescue grassland following pipeline disturbance in southwestern Alberta.

The effects of pipeline construction and reclamation techniques on the restoration of rough fescue plant communities following pipeline construction in southwestern Alberta, Canada were evaluated after 7-40 years. The pipeline construction right-of-way (ROW) sites varied from no recovery of rough fescue grassland to moderate recovery. The ROW sites had a higher proportion of introduced grasses and forbs, less topsoil, and poorer rangeland health than the adjacent undisturbed grassland. Within the ROW sites, less topsoil was present on those with larger diameter pipe and which had topsoil fully stripped from the ROW during construction. Introduced grasses, Festuca ovina (sheep fescue) and Poa compressa (Canada bluegrass), succeeded in establishment following seeding and persisted for at least 40 years. Poa pratensis (Kentucky bluegrass) dominated many of the ROW sites. Contributing factors to moderate recovery of rough fescue grassland were related to post-growing season pipeline construction, ideally, between August and March, summer or fall seeding, and minimum disturbance trench-only stripping. Reclamation practices appeared more important than time since restoration in the restoration of rough fescue grassland.

Establishment of a native bunch grass and an invasive perennial on disturbed land using straw-amended soil

Native grasslands around the word face increased threats from non-native species. Fescue prairie in North America, in good rangeland condition, is dominated by the perennial bunch grass, Festuca hallii, whereas disturbances are often colonized by Poa pratensis, an introduced perennial rhizomatous grass which is competitive in nitrogen rich soils. F. hallii thrives in typical low nitrogen grassland soils and recovers poorly once disturbed. Disturbance to soil caused by well site construction may decrease organic carbon and potassium, and increase nitrogen, phosphorus, pH and electrical conductivity, creating conditions conducive to invasion by P. pratensis. This research tested the hypothesis that F. hallii would tolerate nitrogen depleted soil, through addition of carbon as a straw amendment to newly reclaimed well sites, better than P. pratensis. Our second hypothesis was that F. hallii is negatively affected by disturbed soil and P. pratensis is not. We treated three sites with three straw amendment rates, seeded monocultures of F. hallii and P. pratensis, and monitored establishment over three years. F. hallii biomass, root biomass, leaf length and cover increased in response to straw treatments, whereas P. pratensis showed little response. F. hallii was positively affected by prior-year soil water, and current-year ammonium and potassium. P. pratensis was positively affected by current-year soil water, potassium and nitrate. P. pratensis responded positively to higher pH and electrical conductivity found in disturbed soil and F. hallii responded poorly. The positive relationship of P. pratensis to pH above 7 could explain why it can invade reclaimed disturbed grassland; whereas the negative reaction of F. hallii might explain its failure to recover. We concluded the addition of straw as a soil amendment is a possible solution to poor establishment of F. hallii.

Natural Recovery of Rough Fescue (Festuca hallii (Vasey) Piper) Grassland After Disturbance by Pipeline Construction in Central Alberta, Canada

ABSTRACT: Many attempts to restore grasslands after pipeline construction, including soil manipulation such as topsoil stripping and replacement, and revegetation methods such as seeding native species or non-native cover species, have been unsuccessful. Recent pipeline techniques have used minimum disturbance and revegetation via natural recovery. The goal of this research was to evaluate natural recovery in rough fescue (Festuca hallii (Vasey) Piper) grassland in central Alberta, Canada. Plant species cover was evaluated, comparing pipeline right-of-way disturbances to undisturbed controls. Pipeline construction methods were assessed to determine which would be most successful in returning native grassland species. Pipelines with the most intense disturbances were dominated by wheatgrasses, with abundant bare ground and sparse moss and lichen cover; whereas those with the least intense disturbances had cover similar to native grassland. Results confirmed the importance of minimum disturbance in grasslands. Retaining grassland sod through plow-in pipeline construction and keeping disturbance as narrow as possible is critical to successful recovery. Rough fescue appears to recover better with plow-in pipeline construction than with seeding, most likely from intact sod. Therefore, narrow trenching with plow-in techniques is recommended for grasslands.

Promising Results Restoring Grassland Disturbances with Native Hay (Alberta)

were integral in maintaining the historical structure of the forest. Encouragingly, there is evidence that environmental education efforts by nongovernmental organizations and the Forest Service have been successful in aligning public perceptions and expectations with the objectives of forest restoration (e.g., Ostergren et al. 2008). Engaging stakeholders and educating them on the characteristics of healthy forests and the goals of restoration are the most promising avenues to overcoming generational amnesia presently endemic in the region. Additionally, drawing upon untapped sources of ecological knowledge within the community can also inform management decisions. For instance, an oral history project chronicling Native American institutions may help build cross-generational bridges to traditional practices, such as controlled burning, and shed light on dormant knowledge about regional ecosystems. Aligning public understanding with the reality of fundamentally altered biological conditions is a necessary (though perhaps insufficient) condition for achieving sustainable forest management. We expect that SBS will become a relevant issue not only for restoration in the American Southwest, but also for many other sites across the world. In nearly all contexts, ecological restoration involves community stakeholders. We recommend survey-based assessments of public understanding of the means, objectives, and context of ecological restoration so that SBS is a key component of the social science research agenda. In scenarios where SBS is a likely problem, rigorous documentation of where social perceptions and ecological realities fundamentally differ, and the reasons and the causes for these discrepancies, can help practitioners gain greater support among community stakeholders.

Predicting Grassland Recovery with a State and Transition Model in a Natural Area, Central Alberta, Canada

ABSTRACT: Temperate grasslands worldwide have been reduced to remnants as a result of urban, rural, and oil and gas activities. One of the largest remaining tracts of temperate grassland is located in central Alberta, Canada: a provincial protected natural area known as Rumsey Block. Although Rumsey Block has been protected from urban and rural development, oil and gas activities have been allowed. We analyzed the change in plant communities from several oil and gas disturbances over an eleven-year period. We developed a state and transition model displaying consequences of disturbances from grazing and oil and gas development on rough fescue grassland, considered the reference stable state. Transitions were no, light, or moderate grazing and minimum oil and gas disturbance, such as plow-in pipelines, small area well sites (<25 m2) and sites seeded with native species or left to natural recovery. Triggers, causing change from rough fescue grassland to altered states, were heavy grazing, and moderate to major oil and gas disturbances, such as topsoil stripping and seeding with introduced species. Within the reference state, three plant communities were identified, varying from rough fescue (Festuca hallii) grassland to grazing-induced variations where shortbristle needle and thread (Hesperostipa curtiseta) became dominant. Two altered states were identified: Introduced Grasses and Native Grasses. All altered states were deemed to have crossed a threshold requiring complete eradication of species and reseeding. Based on these results, we recommend minimum disturbance in grasslands, such as light grazing, plow-in pipelines, small areas well sites, and natural recovery.

Restoring Industrial Disturbances with Native Hay in Mixedgrass Prairie in Alberta

Native grassland restorations are often unsuccessful as a consequence of unreliable seed sources and competition from weeds and agronomic species. To improve on conventional approaches, we tested whether native hay can be used as a seed source for restoring native mixedgrass prairie on oil and gas well sites and associated disturbed areas. We also assessed the recovery of grassland that had been cut to harvest native hay. We assessed three wellsites seeded with native hay seven years earlier to evaluate longer term recovery, and they showed significant similarity to controls in adjacent grassland. Additionally, in 2012, five wellsites and an access road were seeded with native hay cut from grassland close to the sites. Grassland cut for native hay recovered within one year, showing similar species composition. In the second year, native hay restored wellsites had significant weedy annual cover; nevertheless, native grasses and forbs germinated, particularly needle grasses, wheatgrasses, and bluegrasses. Three of the native hay restored wellsites were sprayed with a non-selective herbicide in the third year; however, the remaining sites showed good recovery in the third year, with native grasses replacing most of the original weedy species. Collectively, results from this research suggest seeding from native hay is a successful and sustainable technique for restoring native vegetation cover and diversity on industrial disturbances in native grasslands.

Do Three Invasive Species: Amaranthus blitoides, Descurainia sophia and Bassia scoparia, Respond to Soil Properties?

Ecological Restoration Vol. 33, No. 2, 2015 ISSN 1522-4740 E-ISSN 1543-4079 ©2015 by the Board of Regents of the University of Wisconsin System. Do Three Invasive Species: Amaranthus blitoides, Descurainia sophia and Bassia scoparia, Respond to Soil Properties? Peggy Ann Desserud (corresponding author: University of Calgary, Department of Geography, 2500 University Drive NW, Calgary, AB, T2N 1N4, desserud@ualberta.ca) and Christopher Hugenholtz (University of Calgary, Department of Geography, 2500 University Drive NW, Calgary, AB, T2N 1N4).

Effects of disturbance on silver sagebrush communities in dry mixed-grass prairie.

Restoration specialists are increasingly interested in re-establishing silver sagebrush (Artemisia cana) communities due to the large number of wildlife species that are partial sagebrush obligates. Energy development within native grasslands can contribute to habitat loss through introduction of invasive species. In this study, pipeline and reclaimed well site footprints were assessed relative to undisturbed sample units to identify management practices that achieve effective restoration of silver sagebrush communities on disturbed sites. Our objectives were to compare silver sagebrush communities on energy disturbances with undisturbed areas in two ecological range sites in dry mixed-grass prairie: blowouts (hard-packed bare ground) and overflows (mesic sedimentation). Our hypothesis was that moisture, greater nutrient values, and potential seed banks found in overflows may benefit silver sagebrush growth. We were also interested in plant communities resulting from of various seeding treatments, hypothesizing that silver sagebrush may be negatively impacted by some seeding treatments. We used a paired transect design to measure variations in plant species cover in each ecological range type. We found similar silver sagebrush cover values to adjacent undisturbed areas following disturbances on both overflow and blowout ecological range types; however, silver sagebrush was significantly reduced in disturbed areas that were seeded with grass species compared to sites that were allowed to recover naturally. We recommend minimum disturbance practices with natural recovery, avoidance of seeding agronomic cultivars, and in particular preventing introduction of invasive species such as crested wheatgrass.

An Unexpected Response of a Bunch Grass (Rough Fescue) to Arbuscular Mycorrhizae Fungi

differ from one project to the next—establishing one unified seed source policy is not necessarily the desired goal. The focus should be on open discussion and collaboration among land managers and between land managers and researchers. The realities of cross-pollination and propagule dispersal mean that restoration practitioners have a profound influence on not only the natural areas they manage, but surrounding areas as well. Determining best seed source practices will require documenting the origin of seeds, where they are planted, and how the plants from different sources perform. Our survey sheds light on an important component of ecological restoration decision-making. The responses we received will hopefully stimulate conversation, influence future research topics, and cause organizations to take a look at their own policies.