Restoration of smooth brome invasion in Grasslands National Park: a multi-phased approach

Transcription

1 Restoration of smooth brome invasion in Grasslands National Park: a multi-phased approach Restoration Best Practices Workshop Waterton Lakes National Park Darcy C. Henderson Canadian Wildlife Service October 3, 2007

2 Grasslands National Park S. Saskatchewan R. SASKATCHEWAN Swift Current Lake Diefenbaker Moose Jaw QuAppelle R. Regina Northern Mixed-Grass Prairie Cypress Hills Frenchman R. GRASSLANDS NATIONAL PARK West East Weyburn 100 km Havre Milk R. Bear s Paw Mts Missouri R. Little Rocky Mts Glasgow Peck Lake MONTANA Missouri R. Yellowstone R. Williston

3 Grasslands National Park Park Management Plan (2002) invasive alien plants (IAP) significant threat to EI. IAP Assessment & Strategy (2005) smooth brome among TOP 3 threatening species for EI. Research program funded by PCA, EI-ILF ( ). Field study: invaded community-landscape relations Field experiment: invasion & control mechanisms Greenhouse experiment: invaded soil microflora

4 Smooth Brome (Bromus inermis)

5 Smooth Brome (Bromus inermis)

6 Smooth Brome (Bromus inermis) Values & Problem Definition + Positive = Utilitarian agricultural & engineering - Negative = EI composition, structure & function

7 Where is invasion occurring? Reference Ecosystem Identification & Inventory Why is invasion a problem? Invasion Impact Evaluated against E.I. How does invasion occur? Invasion Mechanism & Control Experiments What can we do about it? Restoration Treatment Recommendations

8 Where is invasion occurring? Reference Ecosystem Identification & Inventory More Efficient Early Detection Monitoring Why is invasion a problem? Invasion Impact Evaluated against E.I. How does invasion occur? Invasion Mechanism & Control Experiments What can we do about it? Restoration Treatment Recommendations

9 Where is invasion occurring? Reference Ecosystem Identification & Inventory Why is invasion a problem? Invasion Impact Evaluated against E.I. How does invasion occur? Invasion Mechanism & Control Experiments More Efficient Small-scale Short-term Medium-scale Medium-term Early Detection Monitoring More Effective Rapid Response Eradication Management for Eradication & Revegetation What can we do about it? Restoration Treatment Recommendations More Effective Large-scale Long-term Management for Prevention

10 Reference Ecosystem ID Sampled 47 sites on moisture-landscape gradient. Multivariate analyses for brome/native overlap.

11 Reference Ecosystem ID Smooth brome invades soils with low salinity & high organic C. Smooth brome invades shrub-grassland communities: Snowberry (Symphoricarpos occidentalis) Rose (Rosa acicularis, R. woodsii) Sages (Artemisia cana, A. ludoviciana) Wheatgrass (Elymus lanceolatus, Pascopyrum smithii) Green needle grass (Stipa viridula) Goldenrods (Solidago canadensis, S. mollis, S. missouriensis) Yarrow (Achillea millefolium) GNPC inventory already mapped these polygons

12 Reference Ecosystem ID

13 Invasion Impacts Evaluate data from 47 sampled sites Structural & compositional changes Native Invaded Height (cm) Litter Cover (%) Grass Cover (%) Shrub Cover (%)

14 Invasion Impacts Evaluate data from 47 sampled sites Structural & compositional changes Species Richness 2m Smooth Brome R 2 = 0.37, p < 0.01 Snowberry R 2 = 0.05, p = Foliar Cover (%)

15 Hypotheses for Mechanisms

16 Hypotheses for Mechanisms Bromus inermis

17 Hypotheses for Mechanisms Shade & Solar Energy

18 Hypotheses for Mechanisms Water Use & Soil Moisture

19 Hypotheses for Mechanisms Productivity & Soil Nitrogen

20 Experimenting with Mechanisms Field experiment manipulates resources for restoration Sunlight (mowing canopy) Soil H 2 0 & NO 3 /NH 4 (root exclusion) Brome seed production Native plant survival & growth Greenhouse experiment evaluates soil inoculation needs for restoration Donor soils from invaded & uninvaded Shrub growth, VAM & PLFA

21 Experimenting with Mechanisms Results to date: Canopy removal inc. solar radiation & inc. soil moisture (brighter & moister) 4 3 Leaf Area 2 Index Canopy - Canopy - Canopy + Roots Soil Moisture (mv) Canopy + Roots 0 Jun Jul Aug

22 Experimenting with Mechanisms Results to date: Canopy removal inc. solar radiation & inc. soil moisture (brighter & moister) Root removal inc. soil N Leaf Area 2 Index Canopy - Canopy Available Nitrogen (ug/10cm 2 ) Roots - Roots Soil Moisture (mv) Canopy + Roots + Canopy + Roots 0 06/11-06/26 06/26-07/10 0 Jun Jul Aug

23 Experimenting with Mechanisms Results to date: Canopy removal inc. solar radiation & inc. soil moisture (brighter & moister) Root removal inc. soil N Results to come: Survival & growth of native grasses Invasion impact on soil microflora & shrub growth

24 Action & Engagement Opportunities Early Detection Monitor valleys & coulee bottoms (visitors) Rapid Response & Eradication Herbicide spot-treatment of small patches Management for Site Restoration Composition? Repeat herbicides, inoculants & seed (friends-of) Structure & function? Repeat grazing & mowing (local ag prod) Managing for Park-Wide Prevention Control seed production with grazing & haying (local ag prod) Creative use of prescribed fire & bison grazing (researchers)

25 Acknowledgements Collaborators: John Wilmshurst & Robert Sissons (PCA), Mike Schellenberg (AAFC) Field technician: Krista Fink PCA Ecological Integrity Innovation & Leadership Fund Grasslands National Park of Canada - staff

26 Restoration of smooth brome invasion in Grasslands National Park: a multi-phased approach Restoration Best Practices Workshop Waterton Lakes National Park Darcy C. Henderson Canadian Wildlife Service October 3, 2007