Planting Design Considerations for a Changing Climate As it relates to Natural Channel Design

Transcription

1 Planting Design Considerations for a Changing Climate As it relates to Natural Channel Design Presented by: Amy Bennewies Landscape Architect and Certified Arborist

2 Planting Design Considerations for a Changing Climate How will Plants Adapt to Climate Change? How does this affect Natural channels? What can we do about Invasive species? New criteria for plant selection Creating Diversity Developing Resilience

3 How will Plants Adapt to Climate Change? The truth is- we don t know. But we can make some assumptions about the conditions that they will face Increased drought in summer Rising temperatures, especially in urban areas Temperature extremes Increased rainfall in extreme events (winter/spring) New pests

4 What does this mean for Plants? Opportunistic species will be more likely to dominate Invasive species will be more of a problem Natural plant communities will change Plants may grow faster Establishing new plantings may be more difficult

5 What does this mean for Natural Channels? The Great Lakes are warming twice as fast as the oceans, putting native fish species at risk, and increasing the risk of algal blooms. Phosphorus loading in the lakes is also increased, likely as a result of extreme spring thaws/floods. Schneider Creek, Kitchener, ON

6 Landscape fabric of Ontario Maitland River

7 Role of Natural Channels in the Urban Fabric Grand River

8 What can we do about invasive species? Context sensitive design Invasive species removal plans prior to starting projects Establish new NATIVE plantings quickly Use native seed mixes Limit soil disturbance and added nitrogen Limit the human disturbances- ie. buffer plantings- urban areas and corridors Be aware of new invasives- ie. RBG

9 Fully Functioning? We Need Diversity!

10 Natural Channel Planting Opportunities Natural channels are natural linkages, and some of the largest available natural areas in urban areas Opportunity to plant some of the species that need more moisture Opportunity to use some more weak-wooded species in planting design

11 Carolinian Canada warmest average annual temperatures, the longest frost-free seasons, and the mildest winters

12 Carolinian Species- an important genetic resource Trees Tulip tree (Liriodendron tulipifera) Sassafras (Sassafras albidum) Flowering dogwood (Cornus florida) Red cedar (Juniperus virginiana) Wild crab (Pyrus serotina) Kentucky coffee tree (Gymnocladus dioica) Bitternut Hickory (Carya cordiformis) Swamp white oak (Quercus bicolor) Black oak (Quercus velutina) Pawpaw (Asimina triloba) Hop tree (Ptelea trifoliata) Sycamore (Platanus occidentalis) Eastern cottonwood (Populus deltoides) Black walnut (Juglans nigra) Honey locust (Gleditsia triacoanthos) Black gum (Nyssa sylvatica) Shagbark hickory (Carya ovata) White oak (Quercus alba) Chestnut oak (Quercus muehlenbergii) Shrubs Spicebush (Lindera benzoin) Bladdernut (Staphylea trifolia) Witch hazel (Hamamelis virginiana) Burning bush (Euonymus atropupurea) Buttonbush (Cephalanthus occidentalis)

13 Tennessee- Native Plants Amelanchier laevis Asimina triloba Allegheny Serviceberry Pawpaw, Dog Banana Betula alleghaniensis (B. lutea) Yellow Birch Betula lenta Sweet Birch, Cherry Birch, Black Birch Carpinus caroliniana American Hornbeam, Musclewood, Blue Beech, Ironwood Carya cordiformis Bitternut Hickory, Swamp Hickory Carya glabra Pignut Hickory Carya ovata Shagbark Hickory

14 Tennessee- Native Plants Quercus alba Quercus bicolor White Oak Swamp White Oak Quercus macrocarpa Bur Oak, Mossycup Oak Quercus muehlenbergii Chinquapin Oak, Chinkapin Oak, Rock Oak, Yellow Chestnut Oak Quercus palustris Pin Oak, Swamp Oak Quercus rubra (Q. borealis) Red Oak, Northern Red Oak Quercus shumardii Shumard Oak, Shumard s Oak, Swamp Red Oak, Southern Red Oak Quercus velutina Black Oak

15 Creating Diversity Some policies hinder the use of rare/carolinian species Directly- selecting plants from a very localized region Indirectly- ie. Kentucky Coffeetree as street trees So how do we address this? make safe bets set up the base ecosystem Do look to ELC communities as reference Context sensitive design- ie. research potentially affected local rare populations Push the envelope a little

16 Creating Diversity We can t think about species preservation alone. Too many of our policies focus on preservation only, not on expanding communities. Preservation alone could lead to extinction

17 Creating Resilience Don t forget to check soil type, local conditions. Plant selection should be very specific to location Microclimate is important Buffer plantings increase erosion resistance Quickly establish a diverse NATIVE plant scheme

18 Creating Resilience The goal is to create diverse, healthy native ecosystems for resilience.

19 These woods are lovely, dark and deep, but I have promises to keep, and miles to go before I sleep Robert Frost

20 Thank You!

21 References Tennessee Invasive Plants Council Google maps Native Plants for Tennessee The Known and Potential Effects of Climate Change on Biodiversity in Ontario s Terrestrial Ecosystems: Case Studies and Recommendations for Adaptation, OMNR. Jon Peter, Curator & Plants Records Manager, Royal Botanical Gardens