Cleared massive fallen branch

Yesterday, there were bands of storms working their way across Michigan (and much of the Midwest). Yesterday, too, there was an Elderwise event: "Walk in the Woods," led by professor emeritus, Chuck Olson. Luckily, they didn't get rained out, but there was apparently a near miss:

The thunder shower that came through about 12:20-12:40 was over by the time we started. While we had a brief shower, later, most of the wet stuff was dripping of the trees. When we walked around the lake, I was surprised at the amount of windfall I saw, and especially by the very recent tree that dropped across the path just befoer we got to the side path to the board walk. We got around it (actually over it) and finished our walk without any real difficulty.

I went out there this morning and took care of the MASSIVE fallen branch.

BEFORE, there was a massive branch across the path, making it rather difficult to walk that route:


AFTER, apart from some debris and dug-up earth, the pathway is now clear:


I'm gonna miss this kind of work, even though I probably sweat several pints in the process. It's good, honest, physical labor, and it feels great.

Spring

The crows are back,
Cawing in the rain-beaten morning.
Black heralds of spring.

Whence come trees?

As you walk around Saginaw Forest - or actually any area with trees - you might not have wondered where the trees actually came from. I mean, it was probably never a question that you asked. But do you really know where all that "stuff" that makes the tree actually came from?

Before you check out this video from Veritasium, stop for a moment and make a prediction.

Got it?

Okay, now click, "PLAY":



For all of you who don't have a background in biology, was your prediction correct?

So now that you know where all the mass of a tree comes from, you might have an additional appreciation for why forests (and also deforestation) is important when thinking about the future.

Raking trails in Saginaw Forest

Much of the trails in Saginaw Forest have been raked - by yours truly.





Why did I do all of this? After all, next year, it will all get covered again, right?

Well, each of the last few years, I've had to negotiate walking along the pathways in the springtime, with them in a treacherous semi-frozen, semi-slushed, semi-muddy mess. Over the year, the walking of the trails crushes the leaves, breaking them down. And then, when the snows come, the ground (and leaves and mashed leaves) gets saturated. When this starts to thaw, the leaves produce discontinuous layers of ice, frozen leaves, water, slosh, wet leaves, etc. In other words: a mess.

The idea is that - since most of the soil of the property is sand, and the majority of the paths are gravel laid atop this sand - if I rake the leaves, there will be greater amounts of infiltration in the spring. Furthermore, even in places where the leaf litter buildup and decomposition have accumulated a significant enough layer of soil, raking away the leaves will allow for this soil to be more easily washed away, revealing the gravel path below (thus improving the quality of the pathways - as pathways).

I even raked a trail out to Westview Way, so that it will be easy to stay off the untrodden ground (we don't like unnecessary soil compaction) while walking into the facility:

Saturday Omphaolskepsis: They aren't the oldest trees in the world, but...

In reading through my news items for today, I came across an article describing the fragility old trees in a changing climate:

A report by three of the world's leading ecologists in today's issue of the journal Science warns of an alarming increase in deathrates among trees 100-300 years old in many of the world's forests, woodlands, savannahs, farming areas and even in cities.

The reason behind this increased rate of die-off among old trees? Well, it's not only because the trees are reaching the end of their lives (some trees can live for several centuries, after all), but because the environments in which these trees live are changing. And why is this happening? Well:

"According to one popular theory, trees get a double-whammy when the thermometer rises. "During the day, their photosynthesis shuts down when it gets too warm, and at night they use more energy because their metabolic rate increases, much as a reptile's would do when it gets warmer." With less energy being produced in warmer years and more being consumed just to survive, there is less energy available for growth. "This hypothesis, if correct, means tropical forests could shrink over time," Professor Laurance said. "The largest, oldest trees would progressively die off and tend not to be replaced. Alarmingly, this might trigger a positive feedback that could destabilize the climate: as older trees die, forests would release some of their stored carbon into the atmosphere, prompting a vicious circle of further warming, forest shrinkage and carbon emissions."

In Saginaw Forest, we don't think of the trees as being particularly "old" - at least I doubt that many people think of Saginaw Forest as some sort of primeval wood, but it's important to remember that some of the trees on the property have joined the century club, having been planted waaay back in 1904. And these trees are dying off, although whether it's due to being planted too close or due to physiological exacerbations caused by climate stress (since many of these old Saginaw Forest trees are actually native to more northerly regions of the state), I can't say.

Still, it's something to think about when you're walking through the forest, recalling (in some deep recess of your mind) that you are walking through a forested landscape that - while not a "natural" forest - is in the range of 60-100+ years old. It's still a relatively "new" forest in that way, having not "matured" to be dominated by the climax community that we would have experienced way back in the early 1800s: a hardwood forest of oak, maple, and beech. It may also be sobering to recall that - thanks to climate change and the changed driving forces that our new and future climate have on the local ecology - Saginaw Forest will not be changing to resemble that 1800s forest of Southeast Michigan so much as a forest that would have been more typical of central Ohio.

In sum - and to bring it back to the topic of the paper - the century-plus old trees on the northern side of the property will likely die faster now than they would have if the climate hadn't changed, that those trees will also be more quickly releasing their stored carbon into the atmosphere, and that those reaches of the property are on a destined path toward a climax forest that would have been more recognizable around the Columbus, OH of 1800 than the Ann Arbor, MI of that same time.

Friday Photos: Autumn Pictures from Saginaw Forest

Some photos of the changing season:


The poison ivy are about to lose their leaves. (Still bad to touch them, though.)


The maples near the gate are slowly moving toward their color shifts.


I decided to quit my raking of the path after I realized how much work was going to be falling from branches in the coming weeks. Still: they need to be raked so that they don't turn into muddy lanes come the spring.


Almost stepped on this guy as I was going back into the cabin. He wasn't any wider than my finger!

Monday Musings: Why do people park in front of the No Parking sign?

Yesterday, I encountered a few vehicles that were parked at the gate, despite the plain signage that says that it is not legal to park there. For example, there was this SUV that was parked right in front of the "No parking" sign (just in case you had a difficult time to recognize the sign, what with all the colorful foliage, I've highlighted the sign):



What's more, I decided to look up how many of the previous caretakers kvetched about no parking.

In 2007, in 1991, in 1989 (twice), and in 1987 In other words, it's been a consistent problem.

And I'm sure that the previous caretakers didn't note every single instance of having to report a vehicle (and not every caretaker wrote in the log book, either). I think that the number of people parking at the gate has diminished, but it is still higher than what would be the case if people followed the law.

Friday Photo: Photos from SNRE's campfire

Last Friday, October 12, 2012, was SNRE's annual Homecoming Campfire, and welcoming back of the class of 1962. It was a good turnout this year, with Beet Box providing the food, and the speed at which the food disappeared is a testament to how awesome it was! (It disappeared so fast that - between all the activities I was doing - I wasn't able to take a photo of the spread!)

Anyway, before the Campfire, there was some additional log-splitting that needed doing:

... and I really like that new Fiskars splitting axe that I purchased at the start of the month. It made short work of those ash logs. It's sharp, keeps an great edge, has a perfect wedge for splitting, is well balanced, and is not stupidly heavy.

Prep work also included moving the row boats to a different location:


One can't have people taking pleasure rides in the middle of the night, right? And, also, with all the boats there, it makes it difficult to safely run the wader races:


Happily, we were able to run the wader race early enough in the evening that we didn't have to do the log-sawing competition in the dark:

... looking back through my photos, I think that this was the first time in a number of years that the log sawing was done during daylight hours. Usually, it has been illuminated by the headlamps and flashlights of all the cheering SNREds.

It was a great honor of mine to also take the alumni of the class of 1962 on a tour of the forest; a place that they had come many times 50 years previous, when they were forestry students. They asked many interesting questions, were heartened to know that the property was still being used for research and teaching, were a little discouraged about the consequences of the lack of serious investment in the property, and generally curious about what changes I knew of that had happened between the time of their graduation and last Friday. What was meant to be a 40 minute tour of the lake trail turned into a discussion that was more than an hour long about many different aspects of the history and ecology of the forest. Hopefully, SNRE's alumni relations will help in trying to get these former students to recount some of their memories of the forest.

Sunday Thoughts: Well, that took a bit out of me

Saturday was a day of rest and a general mental haze. Running the Campfire really took it out of me this year, I guess. Still, it was a great time, and there were not many things to pick up afterwards. Now, as the material of the Campfire are being taken away, I am turning toward work.

It's also really a warm and rainy day, with an expected high temperature of 70F. From a low temperature last night of 26F, I am kinda digging this weather.

Friday Photo: SNRE Campfire!

This will be the fourth campfire for which I will be the on-the-ground organizer (you know, because I'm the caretaker). The campfire is part of the University of Michigan's School of Natural Resources and Environment's Homecoming celebrations. We're expecting to have a handful of 1962 alumni at the event, in addition to the local alums who are interested in showing up and showing how things are done. Events like this always seem to gel at the last minute (much like a good souffle), but since tonight is the night, I haven't any photos from this year's campfire.

However, this is a photo from my first year as caretaker (2009). That year, the Campfire was on October 1, 2009, and - as you can see - the trees on the far side of the lake hadn't quite turned yet.



Hopefully, it will be a great Campfire event.

Wednesday Wonderings: Why does mist rise from the lakes in the morning?

During the fall, there many morning when Third Sister Lake produces gouts of mist and steam:



What's going on here? Obviously, the lake is not boiling, and - obviously - there isn't a general fog blanketing the entire forest, so why does the lake look like a pot on the stove? Well, it's due to many of the same principles of what happens when water boils in a pot on the stove, namely evaporation and condensation, but you have to think of these things in terms of heat energy and NOT in terms of water temperature alone.

In the case of boiling water on a stove, water is heated, causing evaporation; the gaseous water requires a certain amount of heat energy to maintain its gaseous state, and if the heat energy of the gaseous water falls below the condensation point, it turns back into liquid water, forming a fine mist. The mist increases in density as the amount of condensing water increases. This is why you see more and more steam rising from a pot of water as it reaches boiling point.

However, it's not only the temperature of the water that you have to consider when thinking about steam formation. In addition to the process of condensation described above, there is also the humidity to consider. In other words, the air itself can only "hold" a certain amount of gaseous water, and this capacity is determined by the temperature of the air; the higher the air temperature, the more water can be held as a gas. This is why there's a lot more steam seen above a pot boiling in very humid conditions than in very dry conditions (even when the air temperatures are identical).

In the case of misty lakes in the morning, all these processes are happening, just like in the example of the boiling pot, except the temperatures are far lower. Throughout the summer, the lake has absorbed and retained a large amount of heat energy in the top layer of the lake. At night -- especially on cloudless nights -- the heat energy in the air rises away from the surface and escapes this local system, thus bringing down the temperature. There is evaporation taking place in the lake, both day and night, thanks to the higher temperatures of the surface of the lake. However, unlike during the heat of the day, at night, since there is a lower temperature, there is less capacity for the air to hold on to gaseous water, and we can measure this as an increase in humidity. As the humidity rises to 100%, the air has a diminishing capacity to hold on to all the water that is evaporating -- due to the heat of the water in the lake -- and so the water almost immediately condenses into mist as it rises from the lake. In fact, if you heat a pot to the same temperature of the lake water, you would see steam flowing up from your pot, even though the water temperature is nowhere near boiling.

Once the sun's rays strike the surface of the water, the humidity is "burned away", in that the local temperature increases enough so that the humidity drops below 100%, thus allowing the air to once again absorb the evaporating water.

Of course, the reason why the lake effectively billows with steam during early fall mornings is due to the relatively large amount of heat stored in the lake combined with one or two significantly cold mornings. The photo above was taken on September 24, 2012, and if we look at the weather conditions measured at the Ann Arbor airport (about five miles away), we see that the overnight temperature dropped to freezing, and the humidity was near saturation. (Of course, this was in an open field, not above a lake, where the saturation would have been 100%.)



Yeah, okay, so this was a bit of a rambling post, but I hope that it helped you understand (if you didn't already) why so much mist rises off the lake on cool autumnal mornings. Of course, there is little reason to necessarily understand the why in order to appreciate the effect. In the end, fall is a veritable feast of sights, just like spring was one of smells, and summer one of sounds.

Thursday Thoughts: Regional Regional impacts due to Arctic melting: The future doesn't look anything like the past

Out of the University of Wisconsin - Madison, there is a brief on the potential future impacts of climate change on the region. (Well, the statements are about Wisconsin, but the impacted areas are definitely not going to stop at the Wisconsin state line.)

Vavrus, an expert on the arctic climate, says the dramatic melting trend is due to rising concentrations of greenhouse gases in the atmosphere warming the planet. He says natural variability may have accelerated the loss of ice in recent years, and he adds that the far north has physical characteristics that make it more sensitive to warming than other parts of the globe.

For one, he explains, snow and ice that normally cover the region reflect most incoming solar radiation back to space, but increased melting exposes land or ocean water that absorb more solar energy and accelerate any warming trend.

In addition, the lowest layer of the atmosphere in the Arctic is thin and prone to temperature inversions that hold warmer air near the ground, promoting even more melting as the region warms.

Vavrus says the Arctic is likely to continue to see pronounced downward trends in sea ice, snow cover, glacier extent, and permafrost. He says that will have major impacts on both natural ecosystems and human communities in the northernmost latitudes.

But the impacts of a warming Arctic could also be felt far beyond the region, including in the Midwest, according to research conducted by Vavrus and his colleague Jennifer Francis at Rutgers University published in the journal Geophysical Research Letters last spring.

"We believe that the winds aloft at the level of the jet stream will weaken and lead to slower-moving and 'wavier' atmospheric circulation patterns," he explains. "Such a change would favor more extreme weather events in middle latitudes, such as heat waves, droughts, floods, and—ironically—cold snaps."

What this means is that we can expect more weather patterns like what we saw this year: warmer winters, warmer springs, warmer summers, less rain on average, more rain in concentrated events, sudden cold snaps; you know: nothing like it used to be.

For Saginaw Forest, this will mean continued take-over by vines, continued lowering of the lake level, accelerated death of pine species, and rapid changes in the plant communities (as well as the insect, amphibians, reptiles, mammals, and birds that live in the forest). Furthermore, if lake levels get any lower than they are now, the near-shore habitat will be completely out of the water, severely limiting the available area for the fish currently in the lake to spawn, thus potentially causing a decline in the total number of fish in the lake.

... good times.

Monday Musings: Cooler morning conundrums

I live in a forest. Perhaps this isn't too much of a surprise for people, but it's a statement of fact. Usually, this means that the temperatures are a few degrees lower than what I'd encounter in town. (Thanks to the urban heat island effect - yes, Ann Arbor has it, even with its trees.)

Sometimes, though, you misjudge the difference between in-town temperatures and what you feel like when you walk outside in a morning.

... and so I now find myself in a long-sleeve shirt, jeans, and shoes (instead of shorts, t-shirt, and sandals)...

Finally cooled off, but it took a while.

On the plus side, though, my commute this morning only took 16 minutes, and I wasn't the only cyclist that I encountered, either. (There were 2 from Wagner, and an additional 2 in town as I cycled along Washington.)

Conducting fish studies: Times have changed

Time was that the humane treatment of animals didn't really extend to fish. As part of a bit of background reading to assess the possibility of conducting an updated fish survey of Third Sister Lake, I found only one article on the topic of fish in this lake, and it was published in 1942.

The very first sentence of the introduction reads:

The complete removal of fish from Third Sister Lake was not carried out for the primary purpose of making a fish population analysis but rather as part of a general investigation on the existing relationship between the fish and fish-food organisms in this lake.

The author continues by clinically describing the process:

The destruction of the fish population was accomplished by means of rotenone (Derris root) which was supplemented by netting-and angling during the 3 weeks previous to poisoning. The actual poisoning process and its effect on the fish and other organisms found in the lakes described by the authors elsewhere in this volume.

The first poisoning operation was carried out on May 6, 1941, before the spawning season and before the aquatic vegetation was extensive enough to hamper the recovery of fish ... Because the first poisoning did not kill all the fish, a second application was made on August 18 and 19 when water temperatures were more favorable. Only a very few adult fish were recovered along with many thousand bluegill and pumpkinseed fry. These were not included in the population total. After that time, however no fish were seen in the lake until June, 1942,when a few long-eared sunfish entered the lake, presumably via the outlet during high water. We believe that the poisoning was 100 per cent effective in the removal of fish in August.

In other words, they poisoned the lake and then collected the fish that floated up to the surface. The first time wasn't good enough to clear the lake, and so they did another application, but didn't include those fish in the survey. Oh, and by the way, no fish were seen until the summer of the following year; likely up-migration from the connecting stream.

Still, the 1941 survey did a few things, such as provide a good estimate of total fish biomass in Third Sister Lake as well as providing a date certain from when there were absolutely no fish in the lake.

Photo Friday: Drought and a comparison of summers

Just like the comparison of "winter" this year and previous ones, it's interesting to look at the condition of this year's drought conditions. The front lawn area is where this year's drought is most evident. The brown lawn looks more like something one sees in California than what one would expect in southeastern Michigan.

From Thursday morning (July 25, 2012):


Compare it with July 23, 2011:


September 7, 2010 (couldn't find a photo from the end of July):


July 23, 2009:


And although the lake appears to continue to be nice and blue and stable, it actually has continued to drop quite precipitously (considering that it's a spring fed lake and all). To wit:

On Thursday afternoon (July 25, 2012), you can see the matted bottom starting to show through the algal mat:


whereas two months ago (May 25, 2012) it was a channel deep enough for it to be a usable fish passage:

Is Michigan to Become the "Buckeye State"?

Living through this summer of far-hotter-than-normal days in Ann Arbor - home to the University of Michigan Wolverines - and working in environmental and natural resource management, I am thinking about the on-the-ground effects of climate change more than often. (Maybe more than is healthy.)

I hope for rain. I hope for cool winds. I hope for clouds even.

We get heavy sun that heats up asphalt, withers trees, and browns the grass. We get hot gusts of dry wind that buffet you into sweat-stained submission. We get few clouds, and those we get rarely carry rain for us.

It's the largest drought area ever declared, but some people are wondering if this is a forecast of things to come, or even the new normal. However, people from Mississippi River managers to Michigan cherry crop farmers to almost anyone paying attention in much of the country is recognizing that there is a massive drought happening and that weather has gone haywire (unless you happen to be Newton Leroy Gingrich).

And these are just the things that are happening right now. For University of Michigan fans, things could well get much worse.

According to research done in 2007 by Daniel McKenney and colleagues, the Ohio buckeye - which is the state tree of Ohio as well as the mascot to Ohio State University - will be shifting northward over the next 100 years. This means they will be shifting into Michigan, moving fromcurrent distributionand possibly into Michigan (according to the CSIROmk35 A1B prediction model)

This will turn Michigan into the new "Buckeye State" (and buckeyes have been growing quite happily in Saginaw Forest for a few years now), which might well get a lot of Michigan (and Michigan State) fans quite angry about the whole thing, and maybe start to think of climate change as something real. Yes, it's a strange way to introduce people to the effects of climate change, but many people have visceral attachments to sports, and for many people this includes university sports (even if they never attended that particular university).

What might make this an even greater blow for University of Michigan fans is that the last known wolverine living in the state died in 2011. With the death of the wolverine - the UofM mascot - and the encroachment of their largest rival's mascot onto home territory, could there be some sort of climate change education and action that come out of this?

While part of this is written as tongue-in-cheek, another part of me is trying to think of ways to get people latched onto simple fact that climate change is not just happening right now, but has been happening for decades already; that the time to act is not tomorrow, but yesterday; and that the fact we haven't done a lot is only going to require us to work all the harder down the line.

Warming temperatures leading to additional lake complications?

This past winter, Third Sister Lake didn't get a complete freeze, and it was possible, as the spring approached, to see algae growing in some of the ice. In March, while we were experiencing temperatures normally part of June weather, I wrote about some of the possible impacts that such weather might bring if they become the norm. I also wrote about some of the possible impacts to Third Sister Lake that such warming might bring.

Well, add to all that one more impact brought on by warming: decreased lake turnover. In a new paper out in the journal Climate Change, Swiss scientists have shown how increased warming in Swiss lakes have decreased lake turnover, and this has brought about increased levels of Burgundy blood algae.

The paper's abstract states:

Anthropogenic-induced changes in nutrient ratios have increased the susceptibility of large temperate lakes to several effects of rising air temperatures and the resulting heating of water bodies¹. First, warming leads to stronger thermal stratification, thus impeding natural complete water turnover (holomixis), which compensates for oxygen deficits in the deep zones^{2, 3}. Second, increased water temperatures and nutrient concentrations can directly favour the growth of harmful algae^{4, 5, 6}. Thus, lake-restoration programmes have focused on reducing nutrients to limit toxic algal blooms⁷. Here we present evidence that the ubiquitous^{8, 9, 10} harmful cyanobacterium Planktothrix rubescens has become the dominant species in a large lake during the past four decades, although the phosphorus content of the ecosystem decreased fivefold. However, the nitrogen input was not diminished concomitantly, favouring this non-N₂-fixing cyanobacterium owing to increased N:P ratios¹⁰. P. rubescens contains gas vesicles that allow for buoyancy to accumulate within the depth of optimal irradiance¹¹. As the toxic cyanobacterium has low consumption by predators¹², water turnover represents the main mechanism of seasonal population control. Thus, unidirectional lake-restoration measures¹³ in parallel with recurrent absence of holomixis owing to lake warming may lead to similar undesired effects that have formerly emerged from fertilization.

This type of impact is problematic for Third Sister Lake, not because of Planktothrix (or because of other cyanobacteria, at least to my knowledge), but because Third Sister Lake is already a lake that doesn't completely turn over. From a 2001 paper by Bridgeman et al., the finding of lake stability (i.e., the resistance to turnover) in Third Sister Lake was that:

Salt-laden water entering Third Sister Lake [during the winter] from [the business lots to the southeast] could eventually lead to the formation of a chemocline. Large vertical gradients of salinity may potentially prolong stratification or altogether prevent mixing. ... If Third Sister Lake follows a similar pattern [to First and Second Sister Lakes], the contribution of a chloride gradient to stability would reach a maximum in March or April ... and the lake ... will remain [thermally stratified] until mid-November.

The paper also reported that - due to forest growth from 1904 - Third Sister Lake didn't fully turn over in the spring (i.e., following ice-out), even back in 1986. The authors of the 2001 paper concluded that:

Given that the lake is now more sheltered [than in earlier decades] and may require about 60% more wind energy to overcome a chlorine gradient, complete spring mixing, which was a common event at least into the 1940s and occurred occasionally until the early 1980s, is now probably rare.

And it's likely to remain rare if increased temperatures become the norm. (That is, unless a significant number of trees fall down, thus increasing the lake's wind exposure.)

Are vines growing faster?

Walking through Saginaw Forest this summer, I have noticed far more vine growth than I recall there being in previous years. Is this just my imagination? Confirmation bias? Or could it have something to do with the really warm winter that we had? (Too, could it have something to do with the differential rates of growth between vines and trees?)

What we know for sure is that the winter of 2011/2012 was a really warm one and March, May and June have been uncharacteristically warm, as well. There has also been less rainfall than usual.

Now, what I'm guessing at is that, since vines require less resources to maintain themselves and grow compared to trees, it seems possible to me that vines have been able to quickly take advantage of the warm spring and start their growth while also being able to continue growing during these more parched months. However, this is just a guess on my part.

What I know is that there are a lot of trees with vines growing on them; the vines themselves are very dense, and there's a lot of poison ivy, too. This radically warm winter, spring, and summer seem to correspond with the basic message of a 2006 paper by Mohan et al. Their abstract reads, in part:

Contact with poison ivy (Toxicodendron radicans) is one of the most widely reported ailments at poison centers in the United States, and this plant has been introduced throughout the world, where it occurs with other allergenic members of the cashew family (Anacardiaceae). ... Rising CO2 is potentially responsible for the increased vine abundance that is inhibiting forest regeneration and increasing tree mortality around the world. In this 6-year study at the Duke University Free-Air CO2 Enrichment experiment, we show that elevated atmospheric CO2 in an intact forest ecosystem increases photosynthesis, water use efficiency, growth, and population biomass of poison ivy. The CO2 growth stimulation exceeds that of most other woody species.
So, poison ivy is expected to be more abundant and a greater lover of the high CO2 future than trees. And this is likely also a cause for the increase vine abundance in general.

We heard news a few months back that the atmospheric concentration of CO2 has increased past 400ppm, which doesn't correspond to the elevated CO2 chambers of Motan et al's study, but as the Motan paper discusses previous studies on increased CO2 and vine growth:

With an increase in CO2 concentration and a corresponding increase in photosynthesis, vines can allocate more photosynthate to additional photosynthetic tissue, because of a low allocation to support tissue relative to other woody growth forms (13, 14, 18, 19). Increasing abundance of woody vines is causing increased tree mortality and reduced tree regeneration in forests around the globe (18, 20–23), potentially resulting in shifts in community composition that may impact carbon cycling and biodiversity (23). Although it is unclear how elevated CO2 will affect the growth of vines in forest environments, the contemporary increase in woody vine abundance may be the result of rising atmospheric CO2 concentrations (19, 23).

The Motan et al paper doesn't discuss the impacts of warmer winters, springs, and summers on poison ivy growth (nor on the growth of other vine species). However, I am going to guess that a large part of the vine growth this year is likely due to the ever increasing CO2 levels and have been exacerbated this year by the unnaturally warm seasons.

Watching the transit of Venus

I'll be (hopefully) watching the transit of Venus tonight at Saginaw Forest. Hopefully:

A) it will be clear enough to see the sun,
B) the viewing glasses will be dark enough not to blind me,
C) there will be enough friends and acquaintances there to share this event that won't happen again until 2117 AD.

If you are not in a place to see the transit (or don't have a means to see it directly), you can watch it live via the NASA site:
http://www.nasa.gov/connect/chat/venus_transit.html

If you live in a city that will have a view, head over to your planetarium; they will likely be quite crowded, but you should also be able to avail yourself to their services (and exuberance) there.

And just in case you don't know if your city is in the viewing area, here's the map of where the transit will be visible:


And - because it is a solar event - the starting time will be at the same relative time around the world: roughly 6pm on June 5, 2012 (if you happen to be living in the same timezone as Michigan, that is).

A rainy weekend, huh?

Well, that's a bit unexpected: rain for the long Memorial Day weekend. I woke up to the sounds of distant thunder and then walked outside (to take my daily photo) and... rain, rain, rain, rain, RAIN! Okay, it's not like monsoon-rain in quantity, but it does look like there will be more rain throughout the next two days.

The forest needs it, what with it being in the peak of bloom.