plants?
Harry Watkins St Andrews Botanic Garden
Getting to know our plants: Raunkiaer’s classification of life forms
Getting to know our plants: the phanaerotypes
Xanthorrhoea australis
Crocus laevigatus
Linaria purpurea Ailanthus altissima
What next for our crackophytes?
What do we know about the origin of our urban trees? – A north European perspective. Sjoman and Watkins 2020
Climate change is pushing our plants out of their comfort zone
Urbanization exacerbated the rainfall and flooding caused by hurricane Harvey in Houston. Zhang et al, 2017
But the way we build our cities is making the effects of climate change more extreme in urban areas, aside from the carbon costs of construction and the Urban Heat Island effect
Novel pests and diseases are being introduced
Invasive species are arriving (and botanic gardens may be hosting future invasives)
Domestic gardens play a dominant role in selecting alien species with adaptive strategies that facilitate naturalization. Guo et al., 2019
Habitat fragmentation
But it gets worse...
What if we have blindspots?
Using big data to improve ecotype matching for Magnolias in urban forestry Watkins et al, 2020
Horticultural literature is often the worst of both worlds: generic and contradictory
44% of schemes approved by the planning system in Scotland are delivered as specified: this means that over half of our major projects are different to what our planners, environmental
monitoring agencies and policy makers think they’re getting
From a forthcoming study by Plant Health Centre Scotland
0% of the biggest tree nurseries in Northern Europe knew what
ecotype the parent trees came from for the trees in their nursery
What do we know about the origin of our urban trees? – A north European perspective. Sjoman and Watkins 2020
In a study of Acer rurbrum, Acer platanoides, Betula pendula, Carpinus betulus, Liriodendron tulipifera
Is it all doom and gloom?
Botanists tend to focus on the observable forms of plant life: we need to consider functional diversity
Welcome to warp territory!
Evolutionary dilemmas, a recap
Two main factors limit plant growth Stress and Disturbance
Disturbance
Disturbance
low stress + high disturbance
high stress + low disturbance
low stress + low disturbance
high stress + high disturbance
low stress + high disturbance = live fast, die young
Papaver rhoeas
high stress + low disturbance = slow and steady
Juniperus communis
low stress + low disturbance = outcompete everyone else
Paulownia tomentosa
Competitor
RuderalStress tolerator
Plant economics lead to trade-offs Maxing out on each strategy isn’t viable
A decision needs to be made about how to allocate every unit of carbon that a plant produces
Competitor
RuderalStress tolerator
Grime, 1977. “Evidence for the Existence of Three Primary Strategies in Plants and Its Relevance to Ecological and Evolutionary Theory”
Strategies for life: major plant groups
Annual herbs Biennial herbs Perennials & ferns
Trees & shrubs Lichens Bryophytes
C
Evaluation of trees growing in Alnarp Arboretum, Sweden Sjoman & Watkins, 2021
Specialist competitors “C” Acer campestre Betula allaghanensis Corylus ferox Liquidambar styraciflua Quercus cerris Tilia mongolica
eg Magnolia (M. dawsoniana)
High relative growth rate Tall and wide canopy Delayed sexual maturity Highly plastic architecture
Intermediate “C/S” Acer pseudoplatanus Liriodendron tulipifera Pterocarya rhoifolia Sorbus ulleungensis Tetradium danielii Toona sinensis
Eg Tulip poplar (L. tulipifera)
M-H relative growth rate Tall growth High investment in seed
production Stronger cell walls
Evaluation of trees growing in Alnarp Arboretum, Sweden Sjoman & Watkins, 2021
Generalists “CSR” Acer pseudosieboldianum Betula albosinensis Cercidiphyllum japonicum Corylus avellana Laburnum angyroides Ostrya carpinifolia Pyrus ussuriensis
Eg Katsura tree (C. japonicum)
Seeds able to persist in seed banks
Produces seed at young age Long leaf-lifespan Short whole-plant lifespan
Evaluation of trees growing in Alnarp Arboretum, Sweden Sjoman & Watkins, 2021
Intermediate “S/CS” Acer monspessulanum Carpinus caroliniana Nyssa sylvatica Prunus serotina Taxodium distichum Zelkova schneideriana
Eg Swamp cypress (T. distichum)
Slow relative growth rate Strong leaf cell walls High investment in lignin Maintains high levels of
non-structural carbohydrates
Evaluation of trees growing in Alnarp Arboretum, Sweden Sjoman & Watkins, 2021
Specialist “S” Abies alba Hippophae rhamnoides Nothofagus antarctica Picea orientalis Picea koraiensis Taxus baccata Tsuga canadensis
Eg Korean spruce (P. koraiensis)
Low relative growth rate Delayed sexual maturity Tightly controlled
morphology / low plasticity Tough, dense, unpalatable
leaves
Evaluation of trees growing in Alnarp Arboretum, Sweden Sjoman & Watkins, 2021
Artificial Intelligence Accidentally Learned Ecology through Video Games. Barbe et al., 2020
It appears that there may actually be general laws in ecology, and confirmation of these is appearing in unusual places - botanists need to think in truly interdisciplinary ways
The challenge we have is not to find more crackophytes, but to find the best crackophytes
Key questions for botanic gardens
Botanic gardens can, and need to, play a central role in bridging between research and practice How can we make sure that the experts in Botanic Gardens speak the same language as people specifying and managing plants in towns and cities?
St Andrews Botanic Garden is probably the most biodiverse place in Fife What can we do to provide deeper insights into our urban plants based on what we see in the Garden?
Botanic Gardens engage with a wide range of stakeholders How can we best work between different interests and support the restoration and development of urban habitats?
Using botanic gardens and arboreta to help identify urban trees for the future. Hirons et al., 2020
A six point plan for our urban plants, adapted from work by Peter Soroye (uOttawa) and team
Leverage interest in evidence-based decisions The Coronavirus pandemic has popularised the language of epidemiology and population ecology - botanists need to capitalise on this
The world is more interested than ever in connections with plants More time at home means people are engaging with plants on their doorsteps, and botanists need to celebrate their local nature
Leverage the restructuring of society post Covid-19 to benefit plants, wildlife and society The pandemic highlights that many things in society NEED to change in a way that benefits society and biodiversity
@PeterSoroye / Ten considerations for conservation policy makers for the post-COVID-19 transition Cooke et al 2020 https://ecoevorxiv.org/6wn7v
Consult with stakeholders and rightsholders It’s easy to take shortcuts during the pandemic but it’s more important than ever that we engage with rightsholders and stakeholders
Recognise the complexities involved in compliance and cooperation How many people hoarded loo roll in March? We need to learn from this when developing conservation and biosecurity protocols and help people adapt