Ecological Restoration

Volume 25 Number 4 December 2007

Editorial

Climate Change, One Project at a Time by Mrill Ingram

Society for Ecological Restoration International

Giant Strides by George Gann

Dedication

Mary Ann Pels (March 28, 1958-July 17, 2007) by Dave Egan, Kevin McSweeney, and Mary Kay LeFevour

Articles

Erosion Control and Restoration of a Sand Dune on the Colville River Delta, Northern Alaska, U. S. A. by Timothy C. Cater, M. Torre Jorgenson, Susan C. Bishop, and Caryn L. Rea

To control erosion on a leveled sand dune in the Colville River Delta, Alaska, workers planted native grasses and willow and then followed up by monitoring plant cover. By the end of the study, plant cover was at 73.9%. Eolian sand dunes like the undisturbed one pictured bottom left are distinctive features of the Colville River Delta, alongside water-filled polygons whose cause, although debated, may be traced to the ground expanding and contracting as temperatures change. Photos by Tim Cater

We undertook a restoration project on 3.6 acres (1.5 ha) of a vegetated sand dune leveled in order to build an airstrip in an oilfield on the Arctic Coastal Plain of northern Alaska. We seeded Nortran tufted hairgrass (Deschampsia caespitosa), a relatively non-palatable native grass, to rapidly develop a ground cover that would stabilize the sandy substrate but not attract wildlife. We transplanted 4400 willow (Salix spp.) cuttings and 11,500 sprigs of American dunegrass (Leymus mollis) and seeded two forb species to increase species diversity and the vertical structure of the plant canopy. Total live cover increased to 73.9%, after three years, limiting wind erosion to less than 5% of the treated area. The seeded and transplanted grasses and the naturally colonizing wideleaf polargrass (Arctagrostis latifolia) accounted for most (66.2%) of the plant cover. Survivorship of transplanted willows after 3 years was 26-34%, and we observed annual incremental increases in cover of willows, seeded forbs, and other naturally colonizing species. We identified 31 vascular plant species in the treated area after three years. Of these, 15 were present before the airstrip was constructed, and 19 occurred in natural sand dune ecosystems in the region. These results demonstrated the feasibility of cultivating locally collected native plant materials to control erosion of a disturbed sand dune in the Arctic, as well as to initiate a longer-term process of ecological restoration.

Oak Woodland Restoration: Understory Response to Removal of Encroaching Conifers by Warren D. Devine, Constance A. Harrington, and David Peter

One of only a few Oregon white oak (Quercus garryana) woodlands maintained by prescribed burning. The purple flowers are the native plant, common camas (Camassia quamash). Photo by Warren Devine

Oregon white oak (or Garry oak; Quercus garryana) woodlands and savannas of the coastal Pacific Northwest are legacies of an anthropogenic fire regime that ended with European settlement in the mid-1800s. Historically, these oak stands had a sparse overstory and an understory dominated by fire-tolerant grasses and forbs. Post-settlement fire suppression resulted in widespread invasion and subsequent overstory dominance by conifers, causing mortality of shade-intolerant oak trees and shifting understory plant communities to shade-tolerant species. In a study on four southwestern Washington sites, our objective was to determine the effects of overstory conifer removal (primarily Douglas-fir (Pseudotsuga menziesii)) on microclimate, native and non-native understory cover, and sapling growth. Overstory conifer removal created a warmer, drier understory microclimate during summer months. Conifer removal had little effect on native understory cover during five years post-treatment; however, cover of non-native plants, primarily grasses and woody understory species, increased significantly during the same period. Height growth of Oregon white oak and Douglas-fir saplings exhibited a delayed, but positive, response to overstory conifer removal, although the treatment response of Douglas-fir was 133% greater than that of oak. Increases in non-native understory cover and the rapid growth of young Douglas-fir indicate the importance of pre- and post-treatment understory management to control undesirable plants and promote native species such as Oregon white oak.

Poplar Island Environmental Restoration Project: Challenges in Waterbird Restoration on an Island in Chesapeake Bay by R. Michael Erwin, Jason Miller, and Jan G. Reese

At 1150 acres, the Paul Sarbanes Environmental Restoration Project at Poplar Island, Talbot County, Maryland represents the largest "beneficial use" dredged material project of the U.S. Army Corps of Engineers (a cooperative project with Maryland Port Administration). Begun in 1998, the 15-year restoration project will ultimately consist of roughly 550 acres of uplands and 550 acres of tidal wetland habitats, with limited areas of dike roads, perimeter riprap, and unvegetated mudflats. Wetland restoration began in the one small section (or "cell") in 2002, but all cells will not be filled with dredged material until at least 2013. As a major objective of the restoration, six species of waterbirds were identified as "priority species" for Chesapeake Bay: American black duck (Anas rubripes), snowy egret (Egretta thula), cattle egret (Bubulcus ibis), osprey (Pandion haliaetus), common tern (Sterna hirundo), and least tern (S. antillarum). Monitoring of nesting activities by these species from 2002-2005 indicated that all species except black ducks colonized the site rapidly. More than 800 pairs of common terns nested in 2003-2004. Because of predation by red fox (Vulpes vulpes) and great horned owl (Bubo virginianus) reproductive success was very low for the terns. Trapping was effective in removing the foxes, and other controls have been applied to opportunistic nesting species including herring gulls (Larus argentatus) and Canada geese (Branta canadensis). An effective public education program on the island has precluded potential ethical concerns about animal control.

Unexpected Outcomes and Adaptive Restoration in Michoacán, Mexico: A Cautionary Tale from Sites with Complex Disturbance Histories by Roberto Lindig-Cisneros

Near the Paricutín volcano in the state of Michoacán, México, agricultural lands were covered with volcanic ash when the volcano erupted multiple times between 1943 and 1952. These lands persist today as barren and mostly devoid of vegetation. Restoration of these lands is limited by high ground surface temperatures during the dry season (close to 70 degrees C at noon) and other factors such as damage by herbivores and storm run-off. We used mulch to overcome the main barrier represented by the high ground surface temperatures, which allowed for the reintroduction of the dominant native pine species. When we did not mulch, and particularly during dry years, pine mortality was close to 100%. This led to the unanticipated consequence of a shrub, hierba de golpe (Eupatorium glabratum), establishing in the sites where the planted trees had died. The shrub, although native, precludes the establishment of other native plant species and creates conditions that are even more of a challenge to restoration. The most efficient measure for restoring sites invaded by E. glabratum is the elimination of the shrubs and with them the layer of volcanic ash. This case study illustrates the importance of approaching restoration as an adaptive management practice because unexpected outcomes are unavoidable, particularly in sites with complex histories of disturbance.

Removal of Salt-killed Vegetation During Tidal Restoration of a New England Salt Marsh: Effects on Wrack Movement and the Establishment of Native Halophytes by Stephen M. Smith

Vegetation in a New England salt marsh undergoing tidal restoration was manipulated to improve halophyte seed dispersal and encourage the expansion of salt marsh plant communities. I created ten openings (150 m squared) in an area of salt-killed freshwater shrubs and common reed (Phragmites australis) - a zone (wrack) that presents a physical barrier to the upstream movement of water-borne seeds from halophyte species. Five openings were extended to the edge of the barrier vegetation to provide a clear passageway to the adjacent recovering salt marsh. The other five were left as isolated clearings, and five uncut plots served as controls. The results showed that the establishment of salt marsh plants was greatly enhanced by removing the barrier vegetation. While plots directly connected to the salt marsh yielded the highest numbers of new halophytes, isolated clearings also had a beneficial effect. These responses suggest that establishment and expansion of salt marsh habitat can be initiated and sustained by wrack removal that facilitates seed dispersal, colonization, and succession, providing an effective alternative to standard assembly restorative approaches such as artificial seeding and planting.

Notes

Cumberland Sandstone Glade Restoration at the William B. Bankhead National Forest (Alabama) by David Borland and Tom Counts

Presence of Soil Surface Depressions Increases Water Uptake by Native Grass Seeds by Jane M. Mangold, Jeremy J. James, and Roger L. Sheley

Adding Nitrogen Controls Yellow Sweetclover in Common Garden Study (Minnesota) by James O. Eckberg, Elizabeth A. Bockman, and Pamela M. Kittelson

Sigurd Olson Environmental Institute: Growing a Positive Future in the Northwoods (Wisconsin) by Pam Troxell , Karen C. Danielsen , Becky J. Brown ,and Theodore J. Gostomski

Formation of a Sustainable Cooperative to Conduct Research on Native Plants and Ecological Restoration (Washington) by Steven O. Link , Sally A. Simmons , Rico O. Cruz ,and Barbara Harper

Book Reviews

A Guide for Desert and Dryland Restoration: New Hope for Arid Lands. David A. Bainbridge. 2007. Washington, DC: Island Press. Cloth, $100. ISBN: 978-1-55963-968-2. Paper, $50. ISBN: 978-1-55963-969-9. 391 pages. Review by Andre F. Clewell

Restoring the Pacific Northwest: The Art and Science of Ecological Restoration in Cascadia. Dean Apostol and Marcia Sinclair, editors. 2006. Washington, DC: Island Press. Paper, $49.95. ISBN: 1-55963-078-7. 509 pages. Review by Ron Reuter

Coral Reef Restoration Handbook. William F. Precht, editor. 2006. New York: CRC Press, Taylor & Francis group. cloth, $109.95. ISBN: 978-0-8493-2073-6. 384 pages. Review by Richard F. Ambrose