3. Purpose of the Study
• Review survival and performance to consider
whether modifications are needed to improve
success
• Consider factors influencing survival and
performance of the plantings
• Identify possible modifications to the practice
as part of the CREP Evaluation FAD deliverable
• Ensure that CREP Riparian Forest Buffers are
protecting water quality
4. Background on CREP Riparian Forest
Buffer BMP
• 764.9 acres planted on 159 farms between 1999‐2006
• Planting mainly in spring, but some fall plantings
• Mostly planted bare root stock, commonly using brush
mats and a limited number of tree tubes
• WAP Planners worked with landowners to define CREP
areas, fencing needs and plant assemblage. Planting
was contracted at a cost of approx $2K/ac. Stocking
typically 440 stems/ac.
• Spot checking for three years after planting
• Replanting possible where survival less than 60%
5. Sampling Design
• Random sample of 10 percent of the planted
areas on 10 percent of the farms planted
between 2000 and 2006.
• Establish plots and measure plant heights and
canopy diameter (both planted and natural
regeneration
• Describe the vigor, competition and site
conditions
• Note damage from flooding, browse and
presence/integrity of fencing, presence of
invasive plants
6. Sampling Process
• Used random systematic sampling techniques
to select 16 farms from a list of all contracts
organized by area planted
• Randomly selected plot centers using GIS
• Used GPS to navigate to the plots
• Confirmed the plot was located in a planted
area and established a 1/10th acre circular plot
7.
8. Survey Practices
• Measured height and the widest diameter of the
canopy for trees and shrubs under 12 ft.
• Identified species of tree or shrub
• Occularly estimated height and canopy diameter
for larger trees and shrubs (natural regeneration)
• Photographed the plot from the four cardinal
directions
• Deducted unplanted areas and weighted the
results of the planted area for plots that were
less than 1/10th acre.
9. Data Compilation and Analysis
• Created a Access database with separate tables
for the farm, plots and plants
• Compared the number of live “likely” planted
stems with the number of stems planned to have
been planted per acre (planned stocking was
approximately 440 stems per acre)
• Calculated estimates of plot canopy coverage for
both planted material, natural regeneration
• Analyzed data at overall program, each farm, plot
and by species
10. Survival and Stocking
• Average Survival was based on estimate 440
plants per acre
• Overall average survival was 18.9 percent
• Stocking was an average of 107 stems per acre
• Variation is high between farms
• Variation is high between plots within a farm
• Variation is high within years
16. Survival by Species
• Wide range of trees and shrubs were planted
but the survival was greatest for a small group
of species. Initial finding suggest:
• Best Surviving Trees –White Spruce, Swamp
White Oak, Green Ash, Black Walnut*
• Best Surviving Shrubs – Red Osier Dogwood,
Ninebark, Highbush Cranberry, Winterberry
17. Performance ‐ Vigor
• Surviving trees with the Best Vigor were
White Spruce, Tamarack, White Pine,
Sycamore, River Birch
• Surviving shrubs with the Best Vigor were
Ninebark, Red Osier Dogwood
• Worst survival and performance –Highbush
Blueberry, Hazelnut, Nannyberry
23. Summary
• Low and highly variable survival
• High competition and tough site conditions
• Natural regeneration is important component of
the buffer
• Fencing is key to natural regeneration
• Benefits of using mats and tubes uncertain
• Difficult to monitor due to limited knowledge of
what was actually planted and existed
• Buffers are present and likely functioning, but
may look different than originally anticipated
24. Options for the future
• Reduce reliance on planting if maintenance is not
possible – emphasize natural regeneration
• Increase stocking and use of containerized stock
• Use wider range of species known to grow in this
area and on the wet sites
• Re‐enrollment will be necessary to achieve full
buffer protection
• Improve site characterization, mapping and
establish continuous monitoring protocol
