Stream Restoration Planting for Success

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1 Stream Restoration Planting for Success Presented by: Dillon Conner Landscape Designer, ISA Certified Arborist September 2015

2 Wetland Studies and Solutions, Inc. Natural & Cultural Resources Consulting Firm: Founded in Staff Consulted on +5,000 project sites encompassing +200,000 acres Stream Restoration > 190,000 lf Wetlands > 1,000 ac created and/or restored Virginia s First LEED Gold-Certified Office Expertise: Archeology Ecosystem Restoration Environmental Engineering Environmental Science Geographic Information Systems Regulatory and Permit Compliance Landscape Design Surveying Arboriculture and Urban Forestry Locations: Gainesville, VA Roanoke, VA Millersville, MD 2

3 The Role of Planting in Stream Restoration Defining Success - What Makes for Successful Stream Planting? Enhances habitat and ecological function of riparian corridor Complements the physical grading of the stream Improves the aesthetic (important in urban areas) Additionally A mechanism for long-term channel stability WSSI Scientists Conducting Benthic Survey on Restored Stream 3

4 Importance of Monitoring Monitoring of stream restoration generates the data that will influence future projects. What grows and what doesn t Is the stream stable Is the planting density appropriate Does the seeding rate provide the necessary coverage 4 Months After Construction 3 Years After Construction Post Construction 4

5 WSSI Planting Components WSSI s planting protocol is developed from 20+ years of monitoring and research data gathered from completed stream restoration projects. Below are a few components that have been influenced by monitoring and research information: Plant Stock Size o Survivability of plant stock Species Composition o Adjustments per environmental factors Species Clustering and Density o Influenced by monitoring efforts Planting Inspection o Ensure quality of finished product 5

6 Plant Stock Size WSSI typically specifies the use of one-gallon size plant stock for riparian buffers and stream bank planting zones. 6

7 Why Use Larger Plant Stock? Research shows that one-gallon stock have a higher survivability rates and lower variability of survival than bare roots and tubelings. Bare root 16% survival rate Tubeling 30 % survival rate Gallon 40% survival rate High survivability of the plant stock is a crucial factor in maintaining the stability of the stream banks especially in the early stages after restoration. While more expensive to buy and install, one-gallon stock is the sweet spot in terms of benefit without becoming cost prohibitive. Other benefits of larger plant stock include: Greater biomass in riparian corridor Increased visibility (community perception) Quicker canopy closure Don t go too large! 7

8 Assessment of Woody Vegetation for Replacement of Ecological Functions in Created Forested Wetlands of the Piedmont Province of Virginia Prepared By: Why Use Larger Plant Stock? Herman W. Hudson III 1, Eli Wright 2, Robert B. Atkinson 2, James E. Perry 1 1 Department of Biological Sciences, Virginia Institute of Marine Science College of William & Mary 2 Department of Organismal and Environmental Biology, Christopher Newport University Selection of woody species and stocktypes appropriate to the environmental conditions and planting at sufficient densities is vital to not only meeting regulatory requirements but ensuring that the ecological structure and functions provided by trees (habitat, primary productivity, carbon cycling etc.) are returned to the landscape. Based on the results of survival analysis the gallon stocktype and primary successional species are better choices across a range of habitats to ensure adequate establishment of trees that will contribute to the ecological structure and functions of restored/created wetlands. 8

9 Seed Mix Species Composition Inclusive mix o E&S cover crops (warm and cool season!!!) Around 35 species of grasses, sedges, rushes, forbs, and woody plants Self-selection (range of wetland and upland species) Planting Stock Around 20 species of overstory trees, understory trees, and shrubs 3 Months After Construction (E&S Cover Crop Coverage) 1.5 Years After Construction (Establishment of Native Seed Mix) 9

10 Species Composition - Built-in Flexibility Simplify the Planting Process As Much As Possible Vegetation schedules divided into groups of 4-8 species Contractor is encouraged to include all species listed on the schedule In recognition that all species may not be commercially available (or be cost prohibitive), each species group has built-in flexibility that enables the contractor to choose a minimum of 3 of the 4 species listed, 6 of the 8 species listed, etc. This inherent flexibility reduces the number of substitution requests submitted to the designer Planting Group 16: Contractor to choose a minimum of 4 of the 6 species listed. 10

11 Sample of Stream Restoration Planting Schedule OVERSTORY SPECIES UNDERSTORY SPECIES SHRUB SPECIES 11

12 Sample of Stream Restoration Seeding Schedule E&S CONTROL GRASSES, SEDGES, RUSHES, FORBS WOODY PLANTS 12

13 Species Composition WSSI has compiled multiple vegetation schedule templates to address a wide variety of site conditions. Each template is then tailored to meet the needs of each site. Factors to Consider When Developing the Planting Palette: Hydrology Sunlight and shade conditions o Defined by extent of tree clearing/preservation Human context o We can t see the stream Cost and availability of species Existing Tree Canopy Preserved (Planting Palette Adjusted to Include Shade Tolerant Species) No Tree Canopy Present (Planting Palette to Include Full Sun Species) 13

14 Species Composition Human Context Reston Kid s Trout Fishing Day Kids Enjoying the Restored Stream Amongst the Established Streamside Plantings 14

15 Species Clustering and Density Diagram of Stream Restoration Planting Zones The stream restoration area is divided into three distinct zones with their own respective species based on their proximity to the stream channel. RIPARIAN BUFFER BANKFULL WIDTH RIPARIAN BUFFER STREAM BANK STREAM EDGE 15

16 Species Clustering and Density WSSI takes a proactive approach to planting to ensure stream bank stability. We incorporate high planting densities and seeding rates along the channel as a result of our monitoring efforts. Density Plant spacing of 3 to 4 feet O.C. on stream banks Plant spacing of 1 per linear foot along stream edge (tubelings or live stakes) Seed mix applied at rate of about 125 lbs. per acre Species clustered in groups of 3-8 plants per species Helps naturalize appearance Highlights individual characteristics of streamside plantings Helps prevent dominance of one species Randomized groupings 16

17 Species Clustering and Density Diagram of Traditional Stream Restoration Planting Plantings in equally spaced rows Willow live stake rows along length of stream edge Very successful establishment and reinforcement of banks Live stake reinforcement Stream bank planting at 4 O.C. 17

18 Species Clustering and Density Example of Traditional Stream Restoration Planting Plantings in equally spaced rows Willow live stake rows along length of stream edge Very successful establishment and reinforcement of banks How can we improve? Salix Nigra Live Stakes Along Stream Edge 18

19 Species Clustering and Density Diagram of Stream Restoration Planting Willow live stakes concentrated in high stress areas Maintained high density of plantings More randomized spacing Greater species variation along stream edge More appealing natural aesthetic Species clustering to promote communities and highlight qualities of individual species Live stake reinforcement Stream edge plantings at 1 per linear foot Stream bank plantings at 3-4 O.C. 19

20 Sample of Stream Restoration Plant Schedule 20

21 Stream Planting Inspections Planting Oversight is Critical in Achieving the Desired Outcome Incorporate in contract Make sure seed mix tags are approved prior to grading Stabilize immediately following final grading Plant stock size and condition Handling and storage Planting technique Spacing and density 21

22 Things We Have Learned Monitoring - If you see something that doesn t work, change it! Planting palette tailored to the site conditions Size matters - one-gallon plant stock has higher survivability Importance of planting inspections February, 2011 May, 2012 July,

23 Questions? Southwestern Virginia Office 1402 Grandin Road SW Suite 211 Roanoke, Virginia Northern Virginia Office 5300 Wellington Branch Drive Suite 100 Gainesville, Virginia Maryland Office 1131 Benfield Boulevard Suite L Millersville, Maryland