08/4/16

Climbing in Carmanah: Part II of an MSc

At the end of my post about the first part of my Master’s fieldwork, I mentioned that there was a thrilling second part coming soon. In this my second blog post, I can say that it was an adventurous and photogenic experience, if somewhat over-generous in mosquito bites.  I only wish there were a third part to my fieldwork, insect-free for once, to round it off nicely.

Carmanah Walbran Provincial Park contains the tallest trees in Canada. It’s a few dusty hours down logging roads from Cowichan Lake on southern Vancouver Island, and that’s probably why not many people go there. It was, apparently, a much more popular destination in the early 90s when the protests that led to its creation were internationally famous; but the intervening years have brought retrenchment and decline to the park’s infrastructure. The trail down to the Carmanah Giant is closed, and the trail upstream is no longer maintained. The park headquarters and a hummingbird research station upstream are both gone, and – most importantly – the road is falling into disrepair.

Matthew chilling on The Needle. Photo Credit: TJ Watt

Matthew chilling on The Needle. Photo Credit: TJ Watt

We were there to collect a second batch of samples for my MSc project on somatic mutation in Sitka spruce. The earlier blog post explains the research – in case you’re interested in an overview — but briefly, somatic mutations are changes to the DNA sequence of individual trees that might help tree species evolve more quickly (or they might not – that’s what we want to find out). Because mutations happen very infrequently, we need to increase our chances of finding some by taking samples from the tops and bottoms of old, large trees. The taller the trees, we think, the more mutations we will find. Although we considered many ways of getting samples from the tops of trees (drone, rifle, slingshot…), climbing them is most efficient and, coincidentally, most fun.

Looking down from the Party Tree past some lichen. Photo Credit: TJ Watt

Looking down from The Party Tree past some lichen. Photo Credit: TJ Watt

When we left for Carmanah Walbran Provincial Park we were eight people departing from three different cities, and once again we had too much cream cheese. It was quite an expedition. From the CFCG there were Sally Aitken, Jon Degner, and myself. There were also three exceptional arborists and big tree climbers, Matthew Beatty, James Luce, and Ryan Murphy, as well as two photographers/videographers/drone enthusiasts, James Frystak and TJ Watt, who dropped by for a few days each and took amazing footage.

Major Tom (aka James) ascending
Photo Credit: TJ Watt

The main difficulty climbing trees this large is getting a rope up into the crown. James Luce calls this process “fishing for tree bass.” He shoots a weight attached to some fishing line over a high-up branch using a giant slingshot, and pulls up larger and larger ropes until there is a solid climbing rope hanging from a solid branch. He then clips into the rope with his harness and mechanical ascenders, and walks up the rope into the canopy. Reaching the top of the rope, he climbs up the limbs to the top like a ladder, attaching himself to trustworthy branches or the trunk as he goes. Once at the top, he collects a few handfuls of needles, drops a tape to the bottom of the tree to measure height, and then either descends or traverses to a nearby tree to sample once more.

Standing in the tops of these trees feels surprisingly solid. The wind makes them sway in big circles, but so slowly that you only notice it when you look at other trees swaying with another rhythm. Because the spruce we climbed were so exceptionally tall, the tops of ordinary trees below look small and far away, and the tops of other large trees are as obvious as church steeples. Throughout the crown the limbs of the trees are draped with mosses and lichens, in thick mats or hanging loosely, which occasionally harbour small plants that would more usually be found on solid ground. Previous research in the Carmanah valley, by Neville Winchester and Richard Ring in the 90s, has also revealed an abundance of canopy anthropods, including roughly 120 new species.

Looking down at the top of the tallest known amabilis in BC, called The Two-Headed Boy for a song and its forked top. Photo credit: James Luce

Since we wanted to register some of the trees we measured with the BC Big Tree Registry, we got to choose names for our spruces. The first two we climbed were 77-meter spires in an open clearing: we named them Major Tom and Ground Control, in honour of David Bowie, but also as a reference to our radio protocol. Ground Control referred to Jon and me at the base of the tree, collecting samples, keeping pedestrians clear, helping with measurements, and answering questions from the climbers about sampling techniques. If Matthew or Ryan were in the canopy we usually referred to them as Canopy 1 and Canopy 2, but by radio James was always Major Tom.

The biggest spruce we found will be named the Party Tree, after the centrepiece of Bilbo’s birthday party in the Lord of the Rings. It was also a tree that we had a bit of party in, though, because all of climbed it at once – five of us that day hanging in the canopy. I think everyone would have loved to spend more time in the monumental crown of that 84.4-meter tree. During some spare time in Carmanah we also found the two tallest recorded amabilis firs in BC, at 60 m and 63 m tall. We’ll submit them to the Registry as well, although I’m sure any diligent big tree hunter could find many taller firs in that park.

Matthew and Jon trying to DBH The Needle. Photo Credit: TJ Watt

Matthew and Jon trying to DBH The Needle. Photo Credit: TJ Watt

I had been worried, before visiting Carmanah, that there might not be enough large spruce for my project… and that was a ridiculous worry. Within 30 minutes walking from the trailhead we found more than enough big trees. We were spoiled for choice. We climbed 23 trees averaging 76 meters – that’s more than double the height of the UBC clock tower, and taller than the sequoia featured in the famous National Geographic composite of tree climbers in winter. Jon and I spent our days rushing madly around on the ground processing samples and measuring things while the climbers rushed around equally madly, although vertically. But it was a successful trip, a fun trip, and (as Matthew pointed out) the sort of trip that quickly becomes legendary. I’m very glad to have met such great people, and seen a bit of the magic of canopy research.

Party in the Party Tree. Photo Credit: Matthew Beatty

Party in the Party Tree. Normally Ryan was moving too fast to take a picture of, but here we got him, as well as James, Jon, and myself. Photo Credit: Matthew Beatty

06/13/16

Heading to Haida Gwaii: Part I of an MSc

The many moods of the Cumshewa inlet and estuary on Moresby Island. Lea took some of these photos

The many moods of Cumshewa inlet and the estuary on Moresby Island. Lea took some of these photos.

Sampling for my Master’s project began in May 2016 when Lea and I drove Bean (our lab truck) out of Vancouver towards Haida Gwaii, with lots of unnecessary gear and too much cream cheese. Our mp3/ipod hookup (which is certainly not considered unnecessary gear) broke 45 minutes into the trip, leaving us with no music except intermittent radio. What followed was an epic 28-hr set of travel conversations, over three days, that I could spend this entire blog post recounting – including a history of each of our entire lives, year-by-year in total detail, since birth. The high point of the trip out was the precipitous mountain scenery between New Hazleton and Prince Rupert; the low point was Lea eating all the M&Ms in the trailmix (REALLY, LEA?).

We arrived at Moresby Camp on Moresby Island, where we camped while we sampled at a nearby clearcut. The campsite sits on the end of a little peninsula into a long inlet from the east coast of Haida Gwaii, at the mouth of a river and surrounded by the highest mountains on the islands. Company consisted of bugs, occasional rain, one massive bear, and a rowdy crack-of-dawn party of birds in the estuary. In the morning, Bill from Taan Forestry took us out to the cutblock (thanks, Bill!). Here Lea won honours with distinction by remembering her bug net. I forgot mine, and regretted it.  Over the next five days we searched for 10 or so tall Sitka spruce to sample. We took samples of needles or buds from the top of each tree, as well as samples of the inner bark from the base of each tree. We also counted rings, took pictures, GPSed things, measured tree heights and diameters, sawed stumps, swatted flies, fell off tree trunks, fell onto tree trunks, fell under tree trunks, and generally worked hard.

You might get the impression that mostly Lea worked while I took pictures. You might not be wrong.

You might get the impression that mostly Lea worked while I took pictures. You might not be wrong.

If you’ve made it two paragraphs into this post without quitting, you’re too committed to quit when I explain my research topic (even if I bore your socks off – not that I will). So, the research: I’m studying somatic mutation, the same kind of mutations that in humans cause cancer. Somatic mutations are mutations (changes to a cell’s DNA sequence) that happen in the body cells of an organism instead of in reproductive cells like the precursors to sperm or pollen. And unlike in humans, somatic mutations can be inherited in trees. Because somatic mutations happen when cells divide, and because trees can be large, we expect there are lots of somatic mutations in trees.

View of the cutblock from the spruce we named Mihail

View of the cutblock from the spruce we named Mihail

What’s interesting about somatic mutations is… a lot of things. Mutations are the raw material for evolution, so if trees boost up their mutation rates with extra somatic mutations, they could adapt more quickly and more closely to local environmental conditions (temperature, precipitation). This could be important for adaptation to changing climates, too. Similarly, long-lived trees need to evolve defenses against the short-lived insects that eat them. Maybe somatic mutations help trees overcome their own long generation times (which slow down evolution) and keep pace with fast-evolving insects. There are other interesting points, too – somatic mutations have to do with ageing, and the evolution of mating systems, and horticultural varieties (pink grapefruits!), and competition between branches and buds, and selection within individual trees.

No one knows for sure how many somatic mutations there are, in a tree’s lifetime, so I’m going to try to find out.  The idea is to sequence samples from the top of the tree and compare them with samples from the bottom of the tree. Differences between the two are somatic mutations. Improvements in sequencing technology mean that these mutations, which happen maybe once in a million or ten million base pairs, should now be possible to detect — we hope. Luckily, for the sake of fun, field technology lags behind sequencing technology, and actually obtaining the samples involves a lot of mucking around in the cutblock with envelopes and a small annoying electric saw.

Our increment bore was a circular saw. Photo: Lea Zhecheva

Our increment borer was a circular saw. Photo: Lea Zhecheva

A few days into sampling we were going a bit crazy. “Smell me,” said Lea, after an overly-long day of tumbling around the cutblock. “I smell good.” I thought that was unlikely, and I refused to comply. But she’d been spending most of her spare time bathing down at the river, because I’d been unmercifully crushing her at board games – and so her options seemed to be either bathing or re-reading Harry Potter while giving me dirty looks. I may be exaggerating the ill-will board games generate, but I’m sure she smelled much better than me. Anyway, clearly a rest day was needed. Our rest day was an all-day hike up Mt. Moresby, which included some good views, some snow, and some interesting plants.

Well, after finding nine suitable trees to sample from (each whimsically named), we took the overnight ferry and drove the long drive back to Prince Rupert.  And now (I hope) you’re clamoring for a Part II to complete Part I of this blog post. Well you’ll have to wait. Not because I’m too lazy to finish it (which is probably why Joane divided her post in two parts), but because sampling Part II hasn’t happened yet. But it promises to be lots of fun, too – we’re planning to climb the biggest spruce we can possibly find… I’ll tell you about it sometime.

Some trees were still upright

Some trees were still upright

12/4/15

Scouring coastal Alaskan forests : a journey through the past (Part 2)

Two wonderful weeks of hard work on the Kodiak Archipelago resulted in a truck loaded with 350 silica-dried needle samples and about as many tree cores from Sitka spruce forests. Happy and satisfied with the amount and spatial distribution of these tree samples, I embark on the ferry full of confidence about the second part of the trip: Sampling on the Kenai Peninsula.

Kodiak Island from the ferry

Bye-bye Kodiak!

Back on the continent, my main objective is to find old-growth forests of Sitka spruce and apply the same sampling design. By doing so, I will be able to compare the genetic make-up of a long-established forest to the young forests of the Kodiak Archipelago. I chose the Kenai Peninsula because it is the most likely origin of the trees that established on Afognak and Kodiak Island.

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Just to remind you the general direction of Sitka spruce expansion.

This second chapter to the Alaska journey will provide the essential baseline data for my project and will help answering the following questions:

 

To what extent is population expansion linked to a drop in genetic diversity?

Are trees at the front of expansion experiencing higher levels of inbreeding than trees in core populations? Are they subject to lower levels of selective pressure?

Do deleterious / advantageous mutations spread more easily during population expansion?

Team number 2 is waiting for me in Anchorage: Jon and Vincent, fresh out of the plane. Two highly motivated Aitken Lab members. Two masters of tree-spotting, mushroom-picking, blueberry-gathering, and wild-cooking. Already on the first day I am tempted to re-name them Witty and Cheeky. But they ended up being “Yonathaaan” (with the strongest German accent you can adopt) and “Young Padawan”.

Jon and Vincent.

The crème de la crème of mushroom pickers.

While the difficulty on Kodiak was to get to big trees before the loggers, the difficulty on the Kenai was to get to big trees before the bark beetle. A devastating outbreak in the 1990s left very little of the pristine, old-growth spruce forest I was looking for. A lot of remaining old-growth lies in a thin strip of wet lowland crunched between the sea and the gigantic Harding Icefield, an impossible target for us and Bean, who likes roads more than glaciers and waves.

But thanks to the help of Ed Berg, bark beetle expert, John Morton, wildlife biologist, and our flawless determination, we finally manage to find beautiful, road-accessible stands of pure Sitka or mixed Sitka spruce-western hemlock forests around the Seward Inlet.

Kenai sampling areas

Sampling locations around Seward

After stalling a few times due to excessive scenic landscapes, we’re back in the coring-trunks-and-snipping-twigs business! We keep the same sampling scheme as on the Kodiak Archipelago: collecting equal numbers of tree needle and tree cores among 4 levels of forest structure (see previous post for details) in several locations, and keeping a distance of at least 50 m between sampled trees. The most striking difference in forest structure with Kodiak Island is that there is no “proper” tree of level 5. For sure there are very large trees (winning DBH: 138cm!), but none of them shows signs of open-growth (large lower branches). To me, this confirms that the canopy on the Kenai is way older than the oldest trees, unlike the canopy of Kodiak Island.

take_five

On the left, a Kodiak #5. On the right, a Kenai #5. Note: the scale on both pictures is represented by a normal-sized human being.

Although finding stands with no sign of recent disturbances was a real challenge on this part of the field trip, we managed to find four suitable sampling areas around the Seward inlet and added 197 trees to the collection. Early August, more than six weeks after having left from Vancouver with Ian, Bean and Jethro, it is time to return home. With a few kilometers added to Bean’s odometer, new or reinforced friendship bounds, beautiful memories of wild landscapes, a total of 550 tree samples and exciting prospects for my PhD research, I can’t wait to process all the data…. and go back on more adventures!

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A last evening up North, somewhere on the Alaska highway

10/2/15

Scouring coastal Alaskan forests : a journey through the past (Part 1)

What does an expanding forest look like?

How hard is it to tell how old a natural forest is?

At what stage during the afforestation of a landscape can we say: “This is a forest.”?

Team #1 at its best.

These are some of the questions I had in mind when I started the 4000-km long road trip to Alaska, with my friend and labmate Ian, also member of the Aitken group, Bean, the famous and beloved Aitkenlab truck, and Jethro the rescued dog toy that has become our mascot over the years.

My goal: reaching the edge of the coastal Sitka spruce forest on the Kodiak Archipelago, and sampling several stands at different distances from the front of expansion. Below is a map showing the Alaskan range of Sitka spruce forest. The arrow indicates the historical route of migration of spruces after the last ice age. Beyond the green line,  You’ll have to look very hard to find any conifer tree, or even any tree taller than you.

Picturekod

Once arrived in Kodiak city, the journey is not over. The forest stands we want to work in require an additional floatplane ride and several miles of dangerous driving on dirtroads. And a dive into welcoming devil’s club bushes.

Spruces from above, loaded with last year’s cone crop. Spot our shadow!

Happy bunny on a flight.

 

On the plus side, the forests are stunning!

Picturekod2

 

There we are, finally. We can start sampling! But wait… sampling what? and how?

Here is what I decided to do:

  1. Find a forest stand (by this I mean a reasonably large continuous undisturbed patch of forest)

    Come on, Ian, look harder

  2. Visually assess the different structural levels (or “cohorts”) of the forest and put them into categories

    cohorts

    The typical cohorts of a mature Sitka spruce stand on the Kodiak archipelago

  3. Randomly select an equal amount of trees (typically 4) per structure level per stand, with a spacing of at least 50m between trees

    DSCN6195

    Ian, we said TREES. Pretty orchids do not fit into the protocol.

  4. From each tree, extract a few needles or bark disk for DNA extraction, and a tree core for age determination.

    A bark sample (there is a thin slice of multiplying cells in there) and a freshly extracted tree core

  5. Go find the next stand

    …before the loggers, if possible (these trees were standing two days earlier).

  6. Somewhere along this iterative process, pick up an additional, valuable team member.
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Hey Sally! Come get bushed with us!

 

I ended up with a slightly structured distribution of stands (Mother Nature wasn’t told about the statistical advantages of spatial uniformity)…

kodiak_sample_map_full

Each pink dot is a sampled stand. (One pink dot might be hiding another)

 

…and occasionally, some fresh fish for dinner (thank you Ian)

Spot the beer… We’re so local.

By matching the age of sampled trees with their genotype across several stands , I will be able to directly monitor the evolution of the genetic makeup of the forest and answer the following questions:

How quickly do newly formed forests accumulate genetic diversity?

How many trees colonised the area, and from where?

Does relatedness among trees increase or decrease as we approach the front of expansion?

 

However, to properly answer these questions, I also need at least one “reference” Sitka spruce population that established a long time ago and can be considered to be in an equilibrium state in terms of genetic structure and diversity. The closest Sitka spruce forest that matches these requirements is on the Kenai Peninsula. That’s where the trip continues! Different landscapes, different challenges, different team, and so, very logically,…. different blogpost.

 

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To be continued…

07/29/14

Welcome to Beautiful Gavin Lake!

In early July, Tyler, Joanne, Ian, Sally, and I (the Aitken lab crew, a.k.a. the A-Team) were dispatched to the BC interior to liberate some pine and spruce tissue samples from the clutches of an army of berry-picking bear cubs.

The REAL A-Team.

The REAL A-Team.

The sneaky bear cubs defending their strawberry patch.

The sneaky bear cubs defending their strawberry patch.

Our destination was the Gavin Lake Forest Education Society camp (http://gavinlakecamp.wordpress.com/), which, among other things, serves as basecamp for many UBC research teams working in the UBC Alex Fraser Research Forest (AFRF) and an annual group of 4th year Forestry students participating in the education-veiled debauchery known as “Fall Camp” (one recent cohort saunaed so hard the sauna roof caught on fire).

The cut block where the two field trials were planted.

The cut block where the two field trials were planted.

Sampling the lodgepole pine seedlings.

Sampling the lodgepole pine seedlings.

Our elite squad of tissue wrangling researchers made the 8 hour trek north to collect lodegepole pine and interior spruce tissue samples from a field site in the AFRF. The field site was established on a recently harvested cut block in spring 2013, and contains two separate field trials, one of lodgepole pine (2200 seedlings) and one of interior spruce (3100 seedlings).  These two field trials are medium-term (10 – 15 year) validation studies for our current common garden experiment at Totem field on the UBC Vancouver campus that are part of the AdapTree project. Such validation studies allow for an understanding of how translatable our results are from a seedling trial conducted outside of both of the species natural ranges, to more realistic scenarios of reforestation in the BC interior. In other words, it will tell us if coddled seedlings in raised beds, experiencing mild Vancouver weather accurately represent the seedlings out there in the wild trying to make it on their own. In OTHER other words, it will tell our graduate students if they wasted the last 5 years of their life. Just kidding, but only just.

The cut block, now 18 months after being clear cut, was home to three black bear families that passed their time munching on the sea of wild strawberries that have since recolonized the site. They were very considerate creatures, always maintain a healthy I’m-not-going-to-eat-you distance.  We also saw several deer around the site.  This little guy was particularly handsome.

Handsome Jack.

Handsome Jack.

Mama and baby eating all the strawberries.

Mama and baby eating all the strawberries.

Seeing as the designated UBC research cabin had already been commandeered by another crack squad of UBC researchers, we were upgraded to the lakeside Prime Ministorial cabin, which was very nice, as you can see here. During our free time in the evening we took advantage of our gorgeous surroundings by swimming, canoeing, and hiking around the lake. I must admit, aside from the mild inconvenience of having to wake up at 7:00 in the morning, it felt like more of a vacation than work.

Work is so HARD sometimes.

Work is so HARD sometimes.

Our humble lodgings.

Our humble lodgings. Sally shows us how to assemble a ‘Glory Bowl’.