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Ecological Restoration
Volume 25 Number 1 March 2007
Guest Editorial
Starting Up-A Reminiscence by William R. Jordan III
Society for Ecological Restoration International
Restoring Our Future by Keith Bowers
News
Offshore Drilling Royalties to Fund Louisiana Coastal Wetland Restoration--Eventually
Report Touts Progress in Halting England's Biodiversity Loss
Programs Take Aim at Saltcedar and Russian Olive Infestations
Honda Program Plants 200,000 Trees in New Zealand
Endophyte May Be Key to Controlling Spotted Knapweed
Iraqi Marshland Restoration Makes Strides
Articles
Effects of Soil Texture, Watering Frequency, and a Hydrogel on the Emergence and Survival of Coated and Uncoated Crested Wheatgrass Seeds by Jane M. Mangold and Roger L. Sheley
Revegetation of degraded shrub-steppe often fails due to intense competition from weeds, highly variable environmental
conditions, and limited soil moisture. The objective of this study was to test whether a commercially available seed
coating and a water-retaining acrylamide copolymer hydrogel would increase seedling emergence and establishment of
crested wheatgrass (Agropyron cristatum) under three watering frequencies and two soil textures. Pots were filled with
one of four soil treatments: field soil, two parts field soil mixed with one part sand, field soil plus hydrogel, or field soil
plus sand plus hydrogel. We seeded the pots with coated or uncoated seed and placed them in a greenhouse for 66 days.
The pots were assigned one of three watering treatments: 4.5 oz (150 ml) applied one time per week, 1.5 oz (50 ml)
applied three times per week, or 0.9 oz (30 ml) applied five times per week. We recorded seedling emergence at three
and six weeks. At the end of 66 days, the numbers of seedlings that survived were counted and aboveground biomass
was collected, dried, and weighed.We found that uncoated seed had 1.6 times greater seedling density than coated seed.
Incorporation of the acrylamide copolymer hydrogel into the potting medium conferred some benefit to emergence, biomass,
and survivorship of crested wheatgrass seedlings. However, it was watering frequency that produced the most consistent
influence on seedling emergence, survival, and biomass. Watering three or five times per week increased
emergence more than watering one time per week, but watering one time per week generally led to greater survivorship
and biomass. This suggests that the use of water-retaining hydrogels may help to overcome soil moisture limitations and
improve seedling establishment during revegetation of degraded shrub-steppe.
A Restoration Practitioner's Guide to the Restoration Gene Pool Concept by Thomas A. Jones and Thomas A. Monaco
Choosing plant materials for each desired species is often one of the most difficult steps in developing a restoration plan.
The Restoration Gene Pool concept was developed to clarify the options available to the ecological restoration practitioner
in terms of plant materials. We present a decision-making flowchart incorporating the issues delineated in the Restoration
Gene Pool concept. We intend to provide practitioners with a framework to make objective and defensible plant
materials choices in keeping with the objectives and philosophy of the restoration project. The flowchart consists of a series
of boxes with single or multiple statements to be judged as true or false. The statements deal with issues such as genetic
identity, plant metapopulation, functional guild, ecoregion, invasive weed presence, site soil and climate, endangered
species presence, commercial seed availability, seed contracting potential, and availability of material bred for improved
stress tolerance. Implementing the flowchart is a straightforward way to apply the Restoration Gene Pool concept to a
particular project, but we encourage each practitioner to personalize the flowchart to make it as practical as possible for
the situations that she or he most often encounters.
Variation in the Initial Success of Seeded Native Bunchgrasses in the Rangeland Foothills of Yolo County, California by M.E. Lulow, T.P. Young, J.L.Wirka and J.H. Anderson
Investigations into the causes of variation in native bunchgrass distributions in California are constrained by the rarity of
extant populations, their highly invaded nature, and their diverse and often unknown historical backgrounds. In addition,
the correlates of success in California grassland restoration projects are rarely monitored. While controlling for seeding
densities, we investigated correlates of establishment success for a mix of native bunchgrasses seeded into a
non-native annual grassland with a history of agriculture and grazing in Yolo County, California. Six native grass species--
blue wildrye (Elymus glaucus), big squirreltail (Elymus multisetus), Idaho fescue (Festuca idahoensis), California melicgrass
(Melica californica), purple needlegrass (Nassella pulchra), and Sandberg bluegrass (Poa secunda)--were drill seeded in the
fall of 1999. In order to minimize recruitment of non-native annual grass seed, the land was prepared with a spring burn
and fall application of glyphosate prior to seeding. Through the third growing season, the cover of planted native grasses
was significantly greater on north-facing slopes than on slopes with southern aspects. This was likely due to more mesic
conditions on such sites rather than reduced competition with non-native plants. In the first growing season, distinct
dense patches of filaree (Erodium botrys) became apparent. Native bunchgrasses overall, non-native grasses, and nonnative
forbs all had significantly less cover inside these patches of filaree. Purple needlegrass was an exception to both of
these trends, being insensitive to both aspect and filaree patches. These results reinforce the reputation of purple needlegrass
as a species with wide ecological tolerance and excellent restoration potential.
The Prairie-Wetland Vegetation Continuum in the Chicago Region of Northeastern Illinois by Marlin Bowles and Michael Jones
We conducted a floristic ordination and gradient analysis of plant communities extending from prairie through
graminoid-dominated wetlands in the Chicago region of northeastern Illinois. Data represented about 450 species
from 103 stands sampled across a gradient of six soil moisture classes ranging from dry to hydric, and included sand,
gravel, dolomite, and loam prairies as well as fen, sedge meadow, floating mat, marsh, and bog. As found in other
Midwestern grassland studies, vegetation aligned most strongly along a soil moisture gradient with individualistic
species distributions forming a hierarchical continuum, and lower species richness at the dry and wet extremes of the
moisture gradient. Most species were infrequent, with about 70 percent occurring at less than 20-percent frequency
and present in less than five communities. Species that were more frequent within communities were also more widespread
among communities, fitting the niche-based model of species distribution. Moreover, less than 20 percent of
all species sampled were significant indicators of soil moisture gradient classes, with most representing mesic and
hydric habitats. Dominant prairie grasses extended from dry to wet habitats, merging with wetland species in
graminoid fen, calcareous seep and sedge meadow habitats. Hydric habitat, represented by calcareous floating mat,
marsh and bog, had fewer dominant prairie species and was dominated by a wetland flora. These results provide compositional
and structural models for managing and restoring vegetation across the prairie-wetland vegetation
gradient of the Chicago region.
Different Restoration Thinning Treatments Affect Level of Soil Disturbance in Ponderosa Pine Forests of Arizona, USA by Julie E. Korb, Peter Z. Fulé and Brian Gideon
Forest restoration in southwestern ponderosa pine forests often consists of tree thinning and prescribed fire. Understanding
the effects of thinning treatments on soil integrity is important due to the potential negative effects on soil properties
and plant composition and abundance. We investigated the effects of harvest severity levels (control, low,
intermediate, high) and harvest systems (machine, hand, whole-tree) on soil profile disturbance, soil bulk density, and
dead woody biomass. There were no significant differences in soil profile disturbance, soil bulk density, or dead woody
biomass among harvest severity levels. The whole-tree harvest system produced significantly larger areas with high levels
of soil profile disturbance and significantly smaller areas with no soil disturbance than either the machine- or handharvest
systems. There were no significant differences in soil bulk density due to insufficient sampling design. Dead woody
biomass was significantly lower in the whole-tree harvested areas than the hand- or machine-harvested areas. Dead
woody biomass can play an important role in providing microsites for plant reestablishment following disturbance. Our
results illustrate that the type of harvest system used in forest restoration treatments is an important factor that needs to
be incorporated into forest restoration design to insure compatibility with overall restoration goals.
Notes
Response of One-year-old Planted Native Grasses to Controlled Burns (California) by Kari E. Veblen, Katherine A. Holmes and Truman P. Young
Restoring Butternut to Southeastern Forests: Determining a Genetic Basis of Disease Resistance (Tennessee) by Sunshine L. Brosi, Scott E. Schlarbaum, Arnold M. Saxton, Robert L. Anderson, Pauline C. Spaine, and Carol Young
Assessing Vegetation, Soil Characteristics, and Growth of Earthen Marsh Terraces in Seven Terrace Fields (Louisiana) by Mark A. Ford, Brent J. Hoffpauir, and George Melancon
Innovative Streambank Restoration at Grand Teton National Park (Wyoming) by Susan E. O'Ney
Ecohydrological Implications of Removing Encroaching Woody Vegetation From a Bur Oak Savanna (Iowa) by Heidi Asbjornsen, L.A. Brudvig, and M.D. Tomer
Experimental Restoration of Wiregrass Communities: A Preliminary Comparison of Herbicide Treatments (Georgia) by Allyson S. Read and Sara H. Schweitzer
Restoring a Longleaf Pine Ecosystem at Allatoona Lake (Georgia) by Terrell Stoves
Burning and Grazing Regime Decimates Quaking Aspen in a Northern Mixed-grass Prairie (North Dakota) by Karen A. Smith and Robert K. Murphy
Can Ultrasound Eradicate Water Chestnut? (New York) by Mei-Yin Wu and Junru Wu
Restoration of Native Bee Pollinators Within the Sacramento River System (California) by Neal M. Williams
Ecosystem Dynamics Simulator: A Powerful Predictive Tool for Vegetation Management and Restoration (Queensland, Australia) by Michael R. Ngugi, Bronwen Jones and Sergei Karabut
The Bluegrass Restoration Program at Griffith Woods (Kentucky) by John J. Cox and Philip H. Crowley
A Long-term, Monitoring-intensive Approach to Pacific Northwest Watershed Restoration by Todd Reeve and Bill Towey
Book Reviews
Under Ground: How Creatures of Mud and Dirt Shape Our World. Yvonne Baskin. 2005. Washington, D.C.: Island Press. Cloth: $26.95. ISBN 1-59726-003-7. 237 pages. Review by Cheryl Lowe
Nature's Restoration: People and Places on the Front Lines of Conservation. Peter Friederici. 2006. Washington, DC: Island Press. Cloth, $25.95. ISBN: 1-55963-085-X. 320 pages. Review by Mary Ann Pels
Abstracts in this issue are from a wide variety of sources including:
Proceedings of the EPA Science Forum 2005: Collaborative Science for Environmental Solutions. Held May 16-18, 2005 in Washington, D.C. Available online: www.epa.gov/scienceforum/2005/
Governor's Restoration Forum: Economic and Public Benefits of Restoring Western Landscapes. Held June 8-9, 2006 in Billings, MT in conjunction with the 10th Billings Land Reclamation Symposium. Presentations and summaries available online: www.restorationforum.mt.gov
Proceedings of the High Altitude Revegetation Workshop No. 17. Held March 7-9, 2006 at Colorado State University in Fort Collins, CO. Available on CD-ROM as Information Series No. 101 from the Colorado Water Resources Research Institute, cwrri.colostate.edu
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