Written by: Bianca Marcellino

The Tundra biome is characterized by extreme cold weather, low biotic diversity and precipitation levels, short growing seasons, low-growing vegetation of simple structure, and nutrients available mostly in the form of dead organic matter. Only a small portion of the permafrost thaws each growing season, called the active layer, which limits the vegetation to low shrubs, sedges, flowering plants, and mosses, all with shallow roots and short reproductive cycles. 

In recent decades, the Tundra has rapidly warmed causing a variety of environmental effects including: melting sea ice resulting in increased water levels, shifting vegetation ranges, and release of CO2 stored in the permafrost. Presently, northern Tundra soils hold ~30% of the total soil organic carbon, which with the continued increase in temperature expected to occur over the next decades, threatening the release of this carbon sink; has alarmed the scientific community and gained the name the “Carbon Bomb”.

The warming temperatures may promote the expansion of the Canadian population into previously sparse areas such as the Tundra, fostered by the increased ability of the Tundra to support a greater abundance of vegetation (Deslippe 2011). This activity serves to counteract the lurking prospect of the carbon bomb ‘explosion’; however, the warming temperatures are also expected to drive native Arctic species further North if they are unable to adapt to the warming climate of their original regions. It is unclear whether the release of atmospheric carbon through the thawing of the permafrost will result in the Tundra becoming a carbon source via heightened microbial activity, or remain a carbon sink through increased vegetation growth.

The question arises - is it possible to plant native Arctic plants, which are well adapted to the current Tundra climate, as a mitigation strategy to help combat the “Carbon Bomb”? This could act to support Artic herbivores and their subsequent food webs, and potentially help to limit their displacement to more Northern areas, but may be impractical given the scale of the Canadian arctic and the limitations in our knowledge of how arctic ecosystems are being impacted by climate change.

This uncertainty clearly identifies the need for further study of Canada’s arctic in order to find the best tools to combat the carbon bomb.

Additonal Reading

National Geographic - Tundra Threats Explained

The Narwhal - Arctic tundra is 80 per cent permafrost. What happens when it thaws?

Sciencing - Plant Adaptations in the Tundra 

References

Deslippe, J. R., M. Hartmann, W. W. Mohn and S. W. Simard. 2011.  Long-term experimental manipulation of climate alters the ectomycorrhizal community of Betula nana in Arctic tundra. Global Change Biology. 17:1625-1636.

Gilg, O., K. M. Kovacs, J. Aars, J. Fort, G. Gauthier, D. Grémillet, R. A. Ims, H. Meltofte, J. Moreau, E. Post, N. M. Schmidt, G. Yannic and L. Bollache. 2012. Climate change and the ecology and evolution of Arctic vertebrates. The Year in Ecology and Conservation Biology 1249:166-190.

Steiglitz, M., A. Giblin, J. Hobbie, M. Williams and G. Kling. 2000. Stimulating the effects of climate change variability on carbon dynamics in Arctic tundra. Global Biochemical Cycles 14:1123-1136.

Treat, C. C. and S. Frolking. 2013. A permafrost carbon bomb? Nature Climate Change 3:865-867.

UC Berkeley Biomes Group, S. Pullen and K. Ballard. 2004. The Tundra Biome. Berkeley University of California.  Berkeley, CA, USA.

Written by: Mary Anne Young

What’s not to like about a plant that flowers while other plants are shutting down for the season?

American Witch Hazel (Hamamelis virginiana), is an understory shrub of North America’s eastern deciduous forests. Although it does have interesting wavy leaves which add character in the forest, or woodland landscape design, throughout the summer, its real beauty is in the late fall when its yellow fall colour drops and it begins to bloom. Few native plants in North America flower in this season, so it is always a delight to me to find a Witch Hazel in full bloom when other plants are winding down for the winter.

The flowers are unique, consisting of twisted thread-like petals with a pleasant scent. It also has an interesting seed dispersal mechanism where the woody seed capsules slowly mature over the course of a year and when it dries to a certain extent splits open to shoot 1-2 black seeds explosively up to 6m (20 feet) in every direction.

Here are some additional details about this fascinating species:

Form: Woody plant, medium to large shrub
Size: 3 – 4m tall and wide
Sun/Shade: Partial shade to full shade
Soil: Clay, Sand, Loam
Habitat: Deciduous forests, stream banks, clearings
Canadian Distribution: Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island (see map above, from VASCAN)

American Witch Hazel

(Hamamelis virginiana) 

View Plant

Witch Hazel is probably most popularly known for its use in medicine historically and today, where its leaves, bark, and twigs are used to make extracts and tinctures. Its tendency to grow along stream banks may have led to the myth that underground water could be found using a forked Witch Hazel branch (water witching).

Understory shrubs of the eastern deciduous forest have a tendency to be overlooked in favour of the delicate spring flowering wildflowers underfoot, or the towering trees overhead. However I challenge you to keep an eye out for Witch Hazel this fall as it puts on a show unrivalled by other forest plants at this time of the year.

Written by: Carl-Adam Wegenschimmel

One of the greatest adversaries to garden and wild plants is the great host of pathogens that regularly attack them. These organisms can belong to a variety of groups, including; fungi, bacteria, nematodes, and viruses. As human beings, we often consider the economic costs these organisms have on our economy, particularly in the agricultural, garden, and forest industries. However, pathogens also play natural roles in our ecosystems, killing sick plants and controlling the population growth of certain species that could otherwise dominate a community.

With the growing concern and insight into climate change, understanding how these understudied groups may affect plants and ecosystems is becoming increasingly important. One of the most noticeable of these groups is fungi!

Fungi attack their plant hosts in a variety of ways, some may first kill their hosts and feed on dead material (necrotrophs), which enter their hosts through wounds and natural openings. Other fungi feed on living tissue (biotrophs) which often enter their hosts in more specialized ways (Doehlemon et al. 2017).

Necrotrophs can sometimes be very destructive, especially when they are invasive species. A well-known example is Dutch Elm Disease (Ophiostoma novo-ulmi), which has severely reduced Elm tree abundance in North America. In this case, the fungus attacks trees with the aid of insects like the Native Elm Bark Beetle (Hylurgopinus rufipes) and the introduced European Elm Bark Beetle (Scolytus multistriatus). Dutch Elm Disease is believed to have originally been introduced from Asia, and so our native Elm trees have evolved little resistance to the fungus (Hubbes 1999). American Elm (Ulmus americana) and Rock Elm (Ulmus thomasii) have suffered the worst with Red Elm (Ulmus rubra) being slightly more resistant. The disease is spread to Elm trees when the beetles feed on twigs in spring time entering and slowly spreading into the trunk of the trees, blocking vascular tissues and eventually killing the host. The beetles are attracted to the diseased elms for breeding and subsequently bore holes into the infected Elms. Eggs are laid inside infected Elms where newly hatching beetles pick up spores and continue the cycle. 

Biotrophic fungi require living hosts in order to feed and have evolved specifically to interact with a living organism rather than a dead one. One of the most visible groups of these plant parasites are the rust fungi, which is one of the largest orders of fungi containing more than 8000 species worldwide (Lorrain et al. 2018). Some rusts cause little damage to their hosts whereas other species are better referred to as hemibiotrophs, which start off as seemingly benign biotrophs but eventually kill their host and act as necrotophic fungi (Koeck et al. 2011).

Some hemibiotrophic rusts are known to cause devastating damage to crops. Other species of rusts are rarely seen but have complex lifestyles like Chrysomyxa pyrolae seen here (right) on American Pyrola (Pyrola americana), which cycles between its Pyrola and Spruce (Picea spp.) hosts. Although this species does not necessarily kill its hosts, it has been observed to negatively affect seed crop in spruce trees (Sutherland et al, 2011).

Written by Carl-Adam Wegenschimmel

The theme of this year’s World Wildlife Day celebration is “Sustaining All Life on Earth,” which recognizes biodiversity as a key component in protecting natural life.

To this end, it is important to acknowledge all species, including those that are often ignored or seen as not having any economic value to humans. We need to take a holistic perspective and recognize the interconnectedness of all living things. Although many plants are valued by people, many other species remain ignored but nonetheless have intrinsic worth and act as key components of ecosystems.

Here in Canada, we are still discovering and learning about our own plant communities. During Ontario Botanists' Big Year 2019 on iNaturalist, Kevin Gevaert discovered a plant that is new to Canada: Slender Three-seeded Mercury (Acalypha gracilens) -- surprisingly within the urban boundary of Caththam-Kent.

This past fall, while I was out exploring a section of the Niagara Escarpment with fellow ecologists Tristan Knight and Jose Maloles, Tristan discovered a moss growing on the cliff face which he identified as Fan Moss (Forsstroemia trichomitria). This species was rediscovered in Quebec in 2011 after not being seen in North America since the late 1800s. Since then, it has only been observed once in Ontario and once in Quebec.

Photo by Carl-Adam Wegenschimmel

Tristan’s discovery marked the second modern record for Ontario and fourth extant record in North America.

Jennifer Doubt, a botanist at the Canadian Museum of Nature in Ottawa, is currently documenting Fan Moss distribution and abundance in Canada, to help understand its conservation status.

Another recent discovery in northeastern North America is the Tall Beech Fern (Phegopteris excelsior), seen for the first time in 2019. Although it hasn’t been documented in Ontario yet, I believe it is only a matter of time before some keen observer is able to separate it from the closely-related and better-known Broad Beech Fern (Phegopteris hexagonoptera).

 I am often amazed in the ability of healthy, mature forests and plant communities to support substantial fungi and lichen communities, with many species still completely under the radar. Here too, there are likely many discoveries yet to be made.

For example, while recently exploring a swamp in Hamilton, I found a species of Chaenothecopsis fungi growing on Paper Birch (Betula papyrifera) which appears to be new to science based on previous collections in Ohio. Another new species of lichen was recently discovered in swamps near Toronto, a stubble lichen (Chaenotheca selvae), which seems to have an affinity for stumps of mature Maple trees.

Photo by Carl-Adam Wegenschimmel

I think that these discoveries underscore how much we have yet to learn, even in places that are generally well-surveyed and emphasize the need to continue to study our ecosystems.

Discoveries like these also highlight the need to protect natural areas, which maintain biodiversity at both the local and global level.

Many wildlife observations today come from citizen science initiatives, which gather the unique experience and knowledge of individuals into centralized databases. These include eBird, created by Cornell University and the Audobon Society, and iNaturalist, offered by the California Academy of Sciences and the National Geographic Society.

These apps make it easy for anyone to contribute to our understanding of biodiversity. This can create newfound appreciation and positive momentum towards sustaining our natural world. One of our big dreams for CanPlant is to use this kind of technology and public participation to enhance our understanding of Canadian plants and landscapes.

Are you an intrepid botanizer who would like to participate in CanPlant's work? You can use our Submit a Photo form to contribute your plant photos, or Contact Us directly if you have a larger collection you'd like to share.

Written by: Nicole White

People used to view wetlands as a waste of space: they can't be built, they can't be easily traversed by boat, and they aren't profitable for most types of agriculture. So why are wetlands so important?

Now we're learning that wetlands are some of the most biologically productive sites on our planet. They hold water in times of flood or drought, purify the environment, and sequester carbon from the atmosphere. I've heard them called 'Nature's Kidneys'. They sustain life by providing essential year-round or seasonal habitat for many species of fish, birds, and other animals. They are also home to plant communities found nowhere else, and have a breathtaking beauty all their own.

Events like World Wetlands Day (Sunday, February 2) work to shift these attitudes, and effect change.

As a small celebration of World Wetlands Day, I conducted an informal poll of my ecologist colleagues to find out what everyone's favourite wetland plant was. The results were fun and I hope our appreciation of these plants inspires you to learn more about them:

Marsh Marigold (Caltha palustris) 'I love Marsh Marigold because the flowers are like little bursts of sunlight when walking through a wetland or swampy woods.'   View Plant
Turtlehead (Chelone glabra) 'Mostly because it looks like a turtle!'   View Plant
Bog Buckbean (Menyanthes trifoliata) 'Bog Buckbean looks like a giant clover, and I've found it in Ontario, Quebec and Nova Scotia.'   View Plant
Buttonbush (Cephalanthus occidentalis) 'The flowers are just so striking... and look like pom-poms or fireworks. They're such a lovely surprise to find.'   View Plant
Skunk Cabbage (Symplocarpus foetidus) 'Foul-smelling but a very reliable groundwater seepage indicator; quite unusual in that its flowers can actually melt the snow so that it can get a head start on flowering and pollination by flies and beetles in the early spring.'   View Plant
Any Type of Bladderwort (Utricularia cornuta shown here) 'They have beautiful flowers, they float on the water surface and they eat bugs. I think that's pretty neat.'   View Plant
Cranberry (Vaccinium macrocarpon) 'It reminds me of Thanksgiving at my family cottage.'   View Plant
Common Pipewort (Eriocaulon aquaticum) 'Stands of common pipewort look like drifts of delicate white pompoms hovering over shallow water. The flower is intricate and the plant is unassuming. Quite lovely.'   View Plant
Pitcher Plant (Sarracenia purpurea) 'Carnivorous -- the story last year that a population in Algonquin consumes salamanders was a bit disconcerting but cool!'   View Plant

We hope you're inspired to learn more about the strange and wonderful plant life growing in our country's wetlands. Check out the links below, or visit the CanPlant Search Page to discover more species.

Recommended Further Reading:

• World Wetland Day 2020: Official Page
Find a World Wetlands Day event near you, learn more about wetlands, get free educational materials and infographic cards to share on your social media accounts.

• The Secret World of Bog
This photojournalist's foray into West Coast coastal temperate rainforest bogs was published in 2016 and won a gold award in the Canadian Online Publishing Awards. The photos in this beautiful piece show the area's flora on all scales, from peat moss fasicles to forests of stunted pines and cedars.

• Pitcher plants discovered snacking on baby salamanders in Ontario park
A recent CBC stories shows that our native carnivorous plants are more voracious than we might think.

• Treasured Wetlands of Nova Scotia 2019 Story Map

An interactive look at wetland habitats in Nova Scotia. If you're not on the East Coast right now, here's a way to visit these sites virtually!