Here’s a bit of a natural history mystery that I found yesterday: this green flower in a bed of White Trilliums (Trillium grandiflorum); something that I had never seen before.
The few initial web references I found suggested this is caused by a bacterium or a virus; further detective work unearthed a 46-year old paper (Hooper, Case & Myers, 1971) that suggests this greening is caused by “mycoplasma organisms”—a kind of bacteria and will cause the plant (eventually) to die.
It sounds like in the ensuing 40+ years since Hooper, Case & Myers published their (3 page!) paper, these “mycoplasma organisms” pathogens have come to be called phytoplasma—see Bertaccini et al., (1999), a paper that references Hooper, Case & Myers (1971).
And with that little discovery, a new world opens: a 2016 paper by Arocha-Rosete et al. that links the disease to a specific strain of phytoplasm: Candidatus Phytoplasma pruni, closely related (like 99% similar) to a phytoplasm called Milkweed yellows phytoplasma.
So…mystery solved?
Because I’m a geek, here’s the reference to the 1971 article: Hooper, G. R., Case, F. W. and Myers, R. 1971. Mycoplasma-like bodies associated with a flower greening disorder of a wild flower, Trillium grandflorium. Plant Disease Reporter, 55: 1108–1110.
Here are the rest of the references I unearthed:
Bertaccini, A., Fránová, J., Paltrinieri, S. et al. European Journal of Plant Pathology (1999) 105: 487. doi:10.1023/A:1008745206438
Arocha-Rosete Y, Morales-Lizcano NP, Hasan A, Yoshioka K, Moeder W, Michelutti R, Satta E, Bertaccini A, Scott J (2016) First report of the identification of a ‘Candidatus Phytoplasma pruni’-related strain in Trillium species in Canada. New Disease Reports 34, 19. doi: 10.5197/j.2044-0588.2016.034.019
Dog Day Cicada Hatching, licensed for use under the creative commons.
I’ve only just noticed a change since our move 100 kilometres south-west from Guelph to London: there’s a different Cicada that makes up the summer-time chorus.
I’m very used to the song of the Dog-Day Cicada (Tibicen canicularis): it’s song has made up the entirety of my summer aural landscape in Southern Ontario. Now that male Cicadas have started to call (I heard my first Cicada calling on July 11th this year), I’m not just hearing the constant sound that characterizes the Dog-Day’s call. Rather, I’m hearing a loud, buzzy, pulsating call. After a little work, I think I’m hearing male Scissor-grinder Cicadas (Tibicen pruinosa). Neat thing is this species is not common in Guelph, but certainly common enough here in London. Looking at a range map, they’re shown to be in Michigan near the Canadian border, but not shown to be in SW Ontario. Perhaps individuals are slowly moving North due to climate change?
The gallivanting hay-eater’s Houdini attempt apparently paid off. City officials said the animal – who they named Molly – will be headed for greener pastures.
“We will find it a home,” said Richard Gentles of the city Animal Care and Control. “We’re starting to reach out to farm sanctuaries.”
Not saying anything that hasn’t been said before, but it is interesting to note that when livestock escapes from abattoirs, something about it qualities change: rather than a member of the herd, it becomes an individual. In that moment, we seem compelled to treat it morally as a different object.
So there is talk in shutting downRiverdale Farm in Toronto as a cost-savings measure (insert reference to gravy here). 2500 of the concerned have taken to Facebook to “Save the Riverdale Farm“. I’m feeling a bit ambivalent about this. On one hand, we have less and less contact with the animals that are responsible for the flesh we eat and modified sweat we consume. So if urbanites can see those animals and make the connection between the disembodied grocery store and a living, breathing organism, that’s a good thing. Is it a better world, however, if these animals weren’t kept at all?
“But,” I hear, “they’re domesticated animals.” How does that change the argument, though?
The Toronto media is ablaze with reports that Giant Hogweed (Heracleum mantegazzianum) has been found within the borders of the GTA. Normally, when an invasive species is found, it does not generate this kind of buzz. Why the hubbub? The sap of Giant Hogweed, on the skin, can lead to a severe skin inflammation called phytophotodermatitis. Many people, however, don’t know how to identify Giant Hogweed or know how tell it apart from Cow Parsnip (Heracleum maximum), a native species (and only somewhat phototoxic).
With the caveat that you should have an knowledgeable plant person confirm any identification, let me quickly outline how you figure out if that plant is Giant Hogweed or something else.
The confounding factor here is all four plants above have white flowers in an umbel (a botanical term to describe the arrangement and shape of the flowers—I’ve included an illustration of what an umbel structure looks like below).
Giant Hogweed Dichotomous Key
So beginning with the assumption that you have a plant with an umbel of white flowers in the GTA, you can try your hand at identification with this key. Please be aware that this key will only work with a mature plant, and Giant Hogweed can take two years to reach the flowering stage. The key is dichotomous, meaning that you will be given two choices. Answer each question with one of the provided choices, go to number and you will come up with an identification.
1: Look at the flower.
If it is 15 cm in diameter (measured from flower edge to flower edge) or larger, go to 3
If it is 14 cm in diameter (measured from flower edge to flower edge) or smaller, go to 2
2: Good news! A small flower means that this is probably not Giant Hogweed. When mature, Giant Hogweed will have flowers up to 1 meter in diameter. It could be Queen Anne’s Lace or Water Hemlock. Note that Water Hemlock is extremely toxic if consumed.
3: Look at the stem of the plant. Is the stem reddish or purple, with spots and stiff bristles?
If yes, go to 4
If no, go to 5
4: This plant is probably Giant Hogweed. To confirm, have a look at the flower. Giant Hogweed has flowers with over 50 rays (a part of the flower structure which I’ve illustrated above). Cow parsnip will have between 15-30 rays.
5: Good news! This plant is probably Cow parsnip. It will have fine hairs, but no stiff bristles. The stem may be purplish, but is mostly green with no blotching or spots. Keep in mind that Cow Parsnip is phototoxic, too.
Keys to a Giant Hogweed ID
Just in case you hate the idea of a dichotomous key, or have questions about a non-flowering plant, here are the key differentiators between Giant Hogweed and other similar-looking plants:
large plant, often over 2.5 m high (when mature)
flowers in umbel shape, larger than 15cm in diameter
flowers have more than 50 rays
hollow stems are between 3-8 cm in diameter
stems have stiff white bristles
stems have spots or blotching, red or purple in colour
OK, I should be editing my dissertation at this very moment, but I came across videos of an event on July 4th, 2010 at Okinawa Churaumi Aquarium, Japan, that I need to share. I found it to be disturbing, as a warning.
There is no doubt in my mind, especially seeing an event like this, that having cetaceans in captivity is not what ought to be done. What is fascinating, however, is to see the reactions of the other companion Dolphins and False Killer Whales. At 1:00 of the footage, the cetaceans watch (I hear echo-locating going on too, but it would be hard to determine from a video like this which of the cetaceans were making the noise) their companion through the pool’s glass enclosure.
I watch this and it makes me sick to my stomach. In part, because I feel deeply empathetic for that whale. Falling out of a pool can’t be enjoyable. While many shows like this one include the cetaceans “gliding out” of the water, the mammals do this on their stomach and are still can get themselves back into the water. Here, the False Killer Whale has no ability to do that. Imagining what that whale is thinking lying there on the concrete is overwhelming.
But it is interesting to hear the crowd’s reaction in the following clip:
As I watched this for the first time, I thought (always the researcher), “Boy, this would be a rich source of data if you could interview these people.” I wondered if this would be some kind of ethically crystallizing moment where a new perspective about whales in captivity could erupt—literally. As you listen to the reactions of the crowd, I hear gasps and giggles. More than anything, perhaps, this event simply reinforced people’s perspectives on whales—there to entertain or as innocent natural objects (or something else). That could be an interesting research question.
Pronunciation: \ˈmi-sən-ˌthrōp\
Function: noun
Etymology: Greek misanthrōpos hating humankind, from misein to hate + anthrōpos human being
Date: 1683 : a person who hates or distrusts humankind
Would you consider yourself a misanthrope? I suspect that most, if asked if they hated or distrusted humanity, would say no. Take ethical consideration, for example. We, who are interested in the more-than-human, often argue that it is the human that sits at the zenith of consideration. And this isn’t strictly an intellectual argument. One has to look at how our culture has chosen to treat, a proxy for consideration, the non-human for confirmation. I have a hypothesis, though. I think that we’re suffering, culturally, from an undiagnosed case of misanthropy.
The Toronto Star is reporting that a local plan to tap Norway Maples (Acer platanoides) this spring, collect sap and boil it down into maple syrup has hit a snag (no pun intended) with the proposal to tap the Norway Maples found in city parks: Toronto’s urban forestry department believes that tapping is “detrimental” to the trees.
When I first read the story, I was concerned that there had been a misquote and the plan was to tap Sugar Maples (Acer saccharum) rather than Norway Maples. I checked in with Laura Reinsborough, fellow graduate from the Faculty of Environmental Studies and project coordinator for Not Far From the Tree (the organization behind this idea) if NFFTT’s plans were to tap Sugar vs. Norway Maples. Not so! NFFTT has a post up that explains the whole program in detail.
For the production of syrup, it looks like they only real difference is the lower percentage of sugar in a Norway Maple’s sap. Typically speaking, it takes 40 litres of Sugar Maple sap to make 1 litre of syrup. Based on their research NFFTT is suggesting they will need to collect 60 litres of Norway Maple sap to get that same 1 litre of syrup. Beyond that, the Norway Maple syrup is supposed to be comparable to Sugar Maple syrup.
While NFFTT has to be polite when dealing with the city, I can be a bit more blunt: I call bullshit on the city’s position. Here’s why. Norway Maples are a non-native species of tree that a preferred for urban planting because they often can deal with the stresses of urban settings better than other species of maples. While urban planting practices are changing, they were often planted as a monoculture: street after street of Norway Maple as the street tree. The problem with the Norway Maple is that individuals are now becoming naturalized (meaning that they are growing from the seeds of planted trees rather than just growing in places where they’ve been planted) in greenspaces throughout Toronto. In turn, they are out-competing native species of trees and quickly replacing a mixed Sugar Maple-American Beech forest that would be the undisturbed normal here in the city of Toronto. Additionally, in comparison with that mixed Maple-Beech forest, Norway Maples shade-out most of the herb layer growing under its canopy. This loss, especially when Norway Maples grow in the ravine system of Toronto, leads to increased erosion. In short, while I dislike dichotomized concepts like native/non-native and invasive/non-invasive, these trees pose a serious ecological problem.
The City of Toronto, to their credit, have recognized the invasive nature of the Norway Maple and publish material describing it as an invasive species [pdf alert] including information on how to control it:
Norway Maple seedlings may be dug out of the ground. Cut small saplings at the base using hand pruners or loppers. Small to medium sized trunks can be girdled.
But do we get the irony yet? The same department that publishes the brochure suggesting that Norway Maples are invasive and should be dug out of the ground, pruned or girdled is the same department now saying the Norway Maples found on city property cannot be tapped for sap.
The benefits of tapping Norway Maples outweigh the concerns. If tapping occurs using time-tested procedures ensuring that over-tapping does not occur1 then there is little, if anything at risk for the health of the tree. There is, as NFFTT outlines, another benefit from this plan: the possibility of citizens’ engagement, understanding of and experience of our “urban forest”. Given that the City is already working to remove Norway Maples, why shouldn’t we find some benefit instead?
Simply, the proper number of taps is based on of the diameter of the tree, never to go beyond four per tree [↩]
A sure sign of spring is the emergence of Eastern Skunk Cabbage (Symplocarpus foetidus). While walking the dogs in the Nordheimer Ravine today, I noticed some cabbage is beginning its 2010 growing season. This is the earliest that I’ve noticed the Cabbage in this location, but it’s also the earliest that I’ve gone looking for it.
This photograph (right), taken in the same spot in 2008, show what the flower will look like in early March.
Inspired by Gregg McLachlan’s recent twitter conversation with Caroline Schultz1, allow me some reasoned conjecture answering what might happen to animals that hibernate in a warming climate.
First, some definitions: hibernation, colloquially-speaking, is the long, uninterrupted sleep that animals undertake to avoid the winter. More correctly, hibernation is one kind of dormancy along a continuum—kinds of deep rest that muddle across periods of time and kinds of organisms, including: torpor, estivation, brumation and diapause. But let’s focus on hibernation2. Two important things happen in hibernation that set it apart from the others I’ve just listed: it involves a lowered body temperature and a lowered heart rate. In turn, this means a lowered metabolism.
Now here in Southern Ontario, we have few animals that enter true hibernation. Bears (and in our case we’re talking Black Bears or Ursus americanus) do not enter true hibernation. But Groundhogs (Marmota monax, pictured below), Eastern Chimpunks (Tamias striatus) and Little Brown Bats (Myotis lucifugus) do.
Now our enjoyment of, as a species of naked apes, the winter season may lead us to believe that other animals enter hibernation to avoid the same cold weather that (some of us) suffer though. The truth is somewhere else—these hibernators have depressed their metabolism so they can avoid having to find food. So, rather than an inability to deal with cold weather, it is the lack of food that has driven the evolution of entering a physiologically dormant state when food disappears.
We’ve (the naked apes in Souther Ontario) have been enjoying a warm period this January and its supposed to get as warm as 6 degrees Celsius on Sunday. Before we tackle the larger question of climate change, what might a warm period like we’ve been having do for those animals hibernating right now?
I’m turning to the great book Winter World: The Ingenuity Of Animal Survival by Bernd Heinrich to help me answer the question and I’m going to focus on the ground squirrels (the Chipmunk and the Groundhog) just to simplify things. Chipmunks and Groundhogs, though they both hibernate, show different strategies in preparation. Simplified: Chipmunks collect food and Groundhogs get fat.
In fact, Heinrich writes that a chipmunk’s “availability of stored food affects whether is remains active or enters [hibernation]” (p.99) meaning that in years with lots of available food, Chipmunks can be active the entire winter and don’t need to suppress their metabolism. This was the subject of an entire doctoral dissertation, so I can’t possibly give a nuanced answer, but being active in the cold seems to be associated more with lots of stored food rather than warmer temperatures. So, for Chipmunks, it will be some combination of the two factors (food & cold) that will predict the depth and length of their hibernation. In fact a Southern species, the California Chipmunk (Tamias obscurus) does not hibernate at all.
Groundhogs are different. They follow something called a circannual calendar—named, to continue our connection to Southern Ontario, by two researcher from the University of Toronto—which means they prepare for, enter and exit hibernation on an internal clock, independent of external conditions.
So, what do these intermittent warm periods do? For Groundhogs, nothing, as they’re busily following the ticking of their circannual clock, waiting for it to rouse them sometime in mid to late February. Like most things in the natural world, there is an exception to Groundhog’s circannual clock: in the U of T experiments, when the air temperature remained above 30 degrees Celsius, the Groundhogs did not enter hibernation. Chipmunks, on the other hand, are easy to rouse, even when in hibernation. Does this mean a longer period of warm weather would wake them up? Perhaps. Likely, those that are active are the Chipmunks with access to food in their cache, so being active, and the higher metabolism, isn’t as serious.
What would a warming climate do? This is where the guess work comes in. Over a long period of time, I would guess that the Eastern Chipmunk would come to resemble its southern cousin and not hibernate at all. For the Groundhog, it would seem that the climate would need to warm a great deal—above 30 degrees Celsius in the wintertime—for them not to hibernate. That’s not an immediate concern right now, and if ever Southern Ontario’s winter temperature ever got to 30 due to global climate change, I think the lack of hibernation would be the least of a Groundhog’s worries.
In the short term, it’s a bit more interesting to guess. Different populations of Groundhogs emerge at different times. This is evident in the fact that Groundhog day falls on February 2nd even though our Southern Ontario Groundhogs emerge later in February. February 2nd is the time of year the southern Groundhogs, specifically those in Punxsutawney, Pennsylvania, generally emerge. This shows some plasticity in the length of that circannual calendar. I would suspect with a warming climate that the clock would begin to change—Southern Ontario groundhogs entering their den later in the year and emerging earlier. Would these climatic changes occur faster than that the circannual calendar could change? I don’t know. For Chipmunks, it would be similar to the long-term changes. Eastern Chipmunks, I suspect, in combination with access to food, will be more active.
What all of this points to though, and what I haven’t really addressed in relation to global climate change, is that access to food continues to be the most important factor associated with hibernators. The question that then needs to be asked: how with global climate change, change the plant communities of Southern Ontario and what impact could that have on the mammals that currently live here?
Perhaps I’ll take a stab at that next time…
circannual calendar
As aside, here’s why Twitter is awesome—before Twitter, how or where else do you get to have an informal chat with the executive director of Ontario Nature and the founder of environmentally-focused career site? [↩]
by Bernd Heinrich to help me answer the question and I’m going to focus on the ground squirrels (the Chipmunk and the Groundhog) just to simplify things. Chipmunks and Groundhogs, though they both hibernate, show different strategies in preparation. Simplified: Chipmunks collect food and Groundhogs get fat.