The Lasting Value of Restoration: A Case Study by the Minnesota

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Spring Peeper Meadow
The Restoration Process
Julia Bohnen and Susan Galatowitsch
Minnesota Landscape Arboretum
History of Wetland Drainage in Minnesota
• More than 75% of wetlands in the
Midwest have been drained
• Most drainage occurred 25-75 years
ago
• In areas of intense agriculture, less
than 5% of wetlands remain
Excavated Tile Line
Wetland Mitigation
• Federal and state laws require that
losses of existing wetlands must be
avoided or mitigated
• For every 1 acre of lost wetland,
2 acres must be restored
• Wetland losses primarily occur in
urban areas now
Retrorse Sedge
Although much wetland restoration is
happening, typically…
• Only hydrology is restored
• Little management occurs after initial
construction
• Natural colonization is relied upon to
re-populate the plant community
• The full complement of wetland types
is not restored
Marsh Milkweed
Restored wetlands do not resemble the native
wetlands they are replacing.
They do not exhibit the diversity of species nor the complex
structure that natural wetlands would have exhibited.
Tree Frog on False White Aster
Even planted wetlands can
have low diversity because
• Planting density is too low
• There is a lack of aftercare
• Plants are placed inappropriately
Tufted Loosestrife
Why Restore or Preserve Wetlands?
•
•
•
•
•
•
Maintain hydrologic function
Flood control
Improve water quality
Habitat
Preserve our natural heritage
Recreation
Interpretive Sign at Spring Peeper Meadow
Spring Peeper Meadow
Is a project of the
Minnesota Landscape Arboretum
and the University of Minnesota
that seeks to improve the practice
of wetland restoration in the
Midwest.
Meadow Wildflowers
Spring Peeper Meadow was Funded
to Demonstrate Successful Mitigation Practices
By Minnesota Environment and Natural Resources Trust
Fund through the Legislative Commission on Minnesota
Resources (LCMR, now LCCMR)
And The Minnehaha Creek Watershed District (MCWD)
Breaking Tile
Spring Peeper Meadow
Landscape Context
• Located west of Chanhassen in Carver
County
• Community context was a mosaic of
Big Woods forest and savanna with
prairie openings and depressional
wetlands
• Rolling landscape
• Historically the area was a shallow
wetland surrounded by Big Woods
The Opportunity
A 30-acre purchase on the east edge of the Arboretum
provided an opportunity to restore a shallow marsh with an
extensive sedge meadow zone
The name “Spring Peeper
Meadow” reflects our
aspirations to restore a
shallow depressional wetland
and the full complement of
species that would thrive in
such a wetland.
The Restoration Team
Arboretum Director – Peter Olin
Ecologist – Dr. Susan Galatowitsch
Landscape Ecologist – Fred Rozumalski
Horticulturist – Julia Bohnen
And many other professionals as needed
A Soil Core Sample
Spring Peeper Meadow Restoration Goals
1. Restore a biologically diverse sedge meadow wetland
2. Demonstrate site preparation, re-vegetation, and after-care
practices
Spring Peeper Meadow – Pre-Restoration
• The land was acquired in 1995
• It had been drained and farmed for more than 80 years
• The basin was a monoculture of reed canary grass and
corn grew on the uplands
Planning & Information Gathering
Watershed
Soil Types
Historic Plant Community
Past Land Use
Current Land Use
Projected Water Depth
Determine Model Plant
Community
Original Concept Drawing
Steps in the Restoration Process
1.
2.
3.
4.
Planted Sedge Meadow Zone
Site Preparation
Restore Hydrology
Re-introduce plants
Aftercare
Site Preparation
Series of herbicide
applications Aug.-Sept.
1995 & May-Sept. 1996
Controlled burn
September 1995
Break Tile
October 1996
Seed Collection & Plant Production
1995 and 1996
Seed
collecting
Greenhouse
production
Nursery
production
Experimental Design
Planting the Wetland
Dormant seed 115 species
Oct.-Nov. 1996
First water on site
Spring 1997
Plant over 60,000 sedges
& forbs May-June 1997
Weed Management
A reed canary
grass plant
Spot treatment
with Rodeo
April-June
A treated
reed canary
grass plant
Restoration Inputs are
Carefully Documented
Plant species
Seedling numbers
Seed quantities
Labor hours by task
Seed collecting
Planted sedges
Mixing seed
Ongoing Research At Spring Peeper Meadow
Vegetation Survey, Large Plot
Vegetation Survey, Small Plot
Amphibian Survey
Breeding Bird Survey
Surface Hydrology
Seed Bank Assay
Seed Longevity Assay
Monarch Butterfly Study
Wetland Community in Transition
1998
2000
April 1998
2002
2004
Lessons Learned at Spring Peeper Meadow
Seeding (vs. planting) is a cost efficient means of restoring a
diverse sedge meadow plant community
Seeding allows species to find an appropriate niche
Have contingency plans to account for uncertain hydrology
Adequate site preparation and aftercare are important for plant
diversity and community development
Reed canary grass is still present in the plant community, but cover
was less than 1% in each of 28 survey plots both in 2000 and 2004
Upland Management
The integrity of the Spring Peeper Meadow wetland
restoration is tied to the landscape around it and to
that end, we have restored and continue to manage
the uplands around the meadow.
Forest Restoration
Prairie and Forest Restorations
Invasive Species Management
Reed Canary Grass
Buckthorn
Leafy Spurge
Garlic Mustard
Birdsfoot Trefoil
Crown Vetch
Purple Loosestrife
Before
After
Buckthorn Removal Project on the Oak Knoll
Prairie and Savanna
Restoration
Historically, small pockets of prairie and
savanna were common near the Arboretum
Our restored prairies and savanna are
managed with herbicides and prescribed
burns
Forest Restoration
Big Woods – 1999
Bare root, dense initial planting
strategy, different sized trees,
16 tree and shrub species,
Sudan Field – 2004
Direct seeded, local seed source,
12 tree and shrub species
Berens – 2006 - 2007
Bare-root, dense initial planting
strategy, 11 tree species
Forest Understory
Restoration
Buckthorn removal and monitoring
reduces competition allowing native
and salvaged wildflowers to re-establish
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