Sorry, I no I haven’t updated in forever, but the semester has been a little busy. I’ve processed most of the cores from the 500+ trees we sampled, which took 2 months longer than I thought it would and pushed back my thesis. I might head out the field again some time this winter just to collect GPS coordinates. Also, I took a week off in October to visit Banff with my gf, so I’ll try to post some photos from that, too.

29.

So this video is me and my lovely Chilean assistants setting up an “extruder”, which is a device that allows you to divide up a lake sediment core into regular intervals. There’s two clamps at the bottom held together by a screw, and by changing the length of the screw you change the size of each slice of the core. Other than that the operation is pretty simple, as you push the cork at the bottom of the tube up through the core, scraping off each layer into labelled zip lock baggies. You can operate an extruder with one person, but its nice to have 2 or 3 people.

Lake sediments can be a fantastic record of past conditions. Lakes obviously occur in low points in the landscape, so eventually everything gets washed into them. Lake sediments in North America typically go back to the end of glaciation, so around 10,000 years, but for my work I’ll only be looking at the last couple hundred.

Lake sediments can contain pollen records, allowing you to recreate historic vegetation, which in turn can track changes in climate and fire history. There are some challenges with pollen though. Some plants spew pollen all over the place, so you see a hundred pollen for that tree for every one pollen from something else, meaning you might miss some species in your counts. Some plants produce pollen that travels for miles and miles, so you might find pollen from plants that actually existed in a completely different region. Some pollen is just a pain in the butt to ID, and all pollen counting is monotonous, difficult and painful.

As mentioned in an earlier post, lake sediments can also contain charcoal from nearby fires. By looking at the size of the charcoal pieces, and their concentration, its possible to distinguish what kind of fire occurred (grass or forest), how big the fire was, and how close to the lake it occurred (All of this depending on the right conditions). As with pollen, there can be difficulties, such as the lake not capturing all fires in the area. If the wind was blowing from the wrong direction that day, most of the charcoal will be blown away from the lake, and can cause you to underestimate the size of the fire, or miss it all together. Therefore, scientists often core several lakes from an area to try to capture the range and frequency of fires more accurately.

So apparently my flash drive that I was editing videos on decided to stop working and formatted itself, AKA is corrupt and wiped my videos. I’ll have to pull them off my camera again. Just in case anyone was wondering why it was taking so long for another upload.

So here’s a terrible video of me coring a tree. I had someone shoot an actual instructional video, But they used their own go-pro, and then went back to Jersey without transferring it onto my computer. 

So, to get a tree core we use a fairly simple device called a borer. Its basically a long screw with a handle and a hollow hole down the centre of the “screw”. The hardest part is the beginning, because you have to shove the borer hard enough while spinning it that the teeth on the screw tip catch on the wood and start pulling themselves in. Its also difficult because at the same time you have to line up the borer with where you think the middle of the tree is, and try to keep it perpendicular to the centre of the tree as well. The aim is to get as close to the very middle of the tree (called the pith) as possible. If its a larger tree you might need a longer borer. 

Borers start at around $600, with bigger or specialized borers costing more, and replacement bores (the screw) starting at around $400. The bores are hand machined and are only made by one family business in Sweden. The bores need to be replaced periodically, because the tip of the borer gets chipped or worn, and can only be sharpened or fix so many times.

Side note, you might hear me saying “hit the bulls-eye”. Some Americans I met at a conference asked me how many times I’d “hit the bulls-eye” and had no clue what they were talking about. Turns out they meant how many times had I hit the pith. I don’t know if they worked with difficult trees, or were inexperienced, but they were proud of having hit it a dozen times or so… I’ve cored a couple hundred trees so I was kind of being an ass and was mocking them.

Transects

For environmental biology, transects are the area you’re going to sample and picking them is incredibly important. Sampling is a fundamental part of your experimental process, and how you choose to sample, where you sample, should be solidly based on what you’re trying to prove. There’s no straightforward way to decide. 

Will you place plots randomly? Will you try to pick ones that are “representative”? Will you sample everything inside a plot, or sample randomly inside the the plot, or will you try to sample a range inside the plot? What you decide should be based on your research question, but also on your funds, how much help you have to collect and process the samples, and how much depth is required to get statistically significant results. Lets say you’re collecting and raising fish, what are the expected mortality rates? Will your samples rot, or will some be otherwise contaminated? There’s a lot of questions to ask, and you can’t move onto the second step of your research until you answer them. Everything else depends on getting that first step right.

Sorry for the lack of updates. I’m looking to do more informational posts, but it has been hard seeing as my 2 volunteers have left. I was joined by another friend, so it is just us two for the remainder of this trip.

#25. 

So, this is a heads up for anyone thinking of doing grad school.

If you have trouble with adapting and dealing with dramatic changes, I would not recommend grad school for you. Unless your research topic is in a well explored area and you basically have your research topic handed to you as part of a larger, already successful effort, there will be changes and set backs through out the process. This is good in some ways, as its better to have it happen as a student, then as a researcher in charge of a $500,000 research grant.

For example, in my case I’ve realized the lake sediments for the area are largely useless, as I mostly wanted them to recreate a fire history for the current trees, but there pretty much hasn’t been any fires there for the last 110 years, and the last fire burned everything. Those trees that did survive are now so big and so old that they’re rotting and collapsing as we speak, so they’re not much use anyways. In response to this, I spent a frantic day searching for new papers that would give me ideas how to salvage this paper. Fortunately, it turns out that people are still heavily debate how Douglas fir re-establish after a fire, with some scientists arguing it takes 10 years, some say 60, and others say it can take up to 300 years. And, because I’ve cored over 500 trees, I have a better data set than a lot of these papers. So I’m now hoping to describe what’s happening on these landscapes, and kick some old man ass.

This means I’ve gone from trying to study the shift in grassland fire frequency from pre-settlement to post-settlement, and link changes to things like severe droughts and small pox, to wanting to model the Douglas fir establishment in a fire free ecosystem, with a focus on the factors influencing succession timing.

Moral of the story, be prepared for setbacks, collect more data (and more types of data) than you think you might need, because you will need at least one fallback plan.

# 24.

This post is about old trees, and I think it tells a lot about how people grow too. 

Tree rings are made of early wood and late wood (image #3). The early wood is the light coloured part of the ring, and these cells are formed during the spring and summer, when water is plentiful and the tree is growing rapidly. The dark part of the ring is the late wood, and its cells are grown during the fall when moisture is scarce. Early wood cells can transport more water and nutrients, but their cell walls are weak. Late wood isn’t as good at transporting resources, but its walls are thick and strong.

Trees that grow in wet places with lots of nutrients have a lot more early wood, and will grow big and tall right away. The tall tree (image #1) is a massive beast with limbs big enough they could be their own tree. You can also tell its age by how its gone flat at the top (this typically happens around 200-300 year old Doug fir), and that its limbs have gotten thicker. But it’s at the base of a hill, and on the edge of a groove in the hillside. This means its getting a tonne of water and is mostly made of early wood. So while this tree is massive, it is at most 400 years old, and probably has a heart full of rot already.

The other tree is growing on the edge of a cliff, on thin soil (image #2). Almost all the rain that falls there, or snow that melts, would run down the cliff immediately, so this tree has grown very slowly. It is mostly made of late wood, and is hard as a rock. Its also over 800 years old. I doubt it has any rot in it, and may live another 200 years if it is lucky.

Like trees, people that grow up with too much for too long are prone to rot. It doesn’t guarantee they’re rotten, but its hard to get to be the biggest tree in the forest without being a little corrupted. In the same way, people that are given just enough every year, and struggle through the years where they got even less than that, have strong hearts that will last centuries. They might not be the prettiest trees, but have a beauty of their own.

There’s a third kind of tree though. The ones that didn’t get enough sunlight, or enough nutrients, or started growing during a year that was just too cold. These trees are dead and will never grow. Their bodies will remain on the earth, sometimes for centuries, and it isn’t always easy to tell the difference between the dead and the living. 

# 23.

Here’s two of the volunteers I found. Since I’m not paying them in money, I paid them in food and beautiful views. Not a bad deal I’d say. They worked hard so the last day they were here I left the one guy by a creek to go fishing and me and the other guy just went hiking. I’ve got a new guy coming out to help me soon though. 

Sorry, I haven't had time to post much lately. I've been out in the field for the past while. I do have some videos however, that I will post when I finish editing them. It may take some time though, as I will be out in the field for possibly another week. Maybe even two depending on what we get done.

#21.

So i got myself some volunteers and I’ll be doing some instructional videos to help prepare them. We’ll be spending a couple weeks out in the field, so I hope this works out and they’re not incompetent.

#20.

So, my supervisors said its up to me to organize and run my next trip out to the field. This is fine, but it means I need to find volunteers. Thankfully I’ve got some friends who are interested, along with some current and former employees at my lab. A couple of the volunteers have 0 relevant experience, so I’m gonna shoot a video of me teaching them how to core trees. 

#19.

Another time I was out in the field I found this awesome little wood fort someone had built and so I ate my lunch in it. On the same hike i came across this pile of ash with some dried rose petals, a ring, and a broken cell phone sitting in it. I dunno if it was someone’s ashes or what, but we all tried to avoid stepping in it.

#18.

They blocked off one of our work sites once, because just before we were gonna head out a bear killed a hiker. It always pisses me off when I see tourists trying to get close to wild animals. Just because there’s nothing really dangerous where you live, does not mean the elk, moose, black bears, and especially grizzly bears here will not fuck your shit up beyond belief. Especially if there’s a baby involved. If I recall though, they figured this just looked like a case of bad luck, he must have stumbled into it and startled it. It didn’t eat any of him, so it wasn’t hunting humans.

#17. 

Just going through some old photos of mine. This was from when we came out to collect data from our weather station, which is like a 3 mile hike. It was April, but a cold front had swept in over the mountains, so it was like -5 out, and there was over a foot of snow over the ground in some places. Sucked. On the plus side, there was a bunch of deer hanging out in our yard.

#16. 

Just some footage at an old site we’re collecting some cookies from (hence the chainsaw noise). For living trees we collect cores (I’ll upload a video of this later) which only leave behind a relatively small hole. The impact of coring has been studied, and its been shown that just using a (relatively) clean borer has almost no impact on trees, and most trees seal themselves back up with resin within a day of coring. Using putty to seal the hole or some sort of anti fungal agent on the borer is more harmful to the tree than just letting it heal naturally.

For dead trees we collect cookies (also called discs), which is a slice of the whole or part of a tree. If the tree is standing, or is just too wide we might only get part of the disc, which is still helpful. Cookies are important for two reasons. First, these dead trees may have laid on the landscape for hundreds of years, and therefore allow us to push our tree ring record back hundreds of years further. My lab has one site where the oldest living tree goes back to around 1200 a.d., but thanks to the abundance of dead old trees our record goes back to around 550 a.d. Secondly, sometimes tree rings will squeeze together along portions of the tree (asymmetric growth or just thin rings), and by collecting the entire disc you can see when this happens. 

Just a view of one of the lakes we considered working at. The lake is natural (man made lakes obviously only have lake sediments since the lake was made), its surrounded by hills (so more of the sediments would blow into or be washed into the lake), and its fed by ground water (streams can disrupt sedimentation by carrying away sediments). More importantly the farmer gave us permission to work on the land and was eager to help if we needed any. Unfortunately its too far north for there to be Douglas fir on the grasslands. Here, they’re all in the mountains.

#14.

So today seems to be insect day. This site is saturated with fire ants, I’ve been bitten maybe 50 times (I chose a great day to wear ankle socks and shorts). However, their presence is relevant to my research.

So a plant’s distribution is determined by a variety of limiting factors, and typically there’s only really one limiting factor in play at a time (that which is in least supply relative to the plants needs). So for Douglas fir, the big controlling factors are temperature and moisture. Temperature matters on kind of a North South gradient. The plant grows as far North as it can, until it becomes too cold and the growing season is too short. The plant grows as far south as it can until it becomes too hot, and it is beaten out by plants better adapted to extreme heat and water loss.

However, I’m working in kind of the middle of that temperature gradient, so moisture is the limiting factor instead. At my sites, you can tell how wet an area is by looking at the trees. If its really wet you get aspen. If its kind of wet you get spruce. If its kinda dry you get Douglas fir, and if its really dry you get Limber pine. Today’s site is next to a lake, so it should be too wet for Douglas fir. However, the soil here is really sandy (which is unusual for the region, most soil here is pretty... dirty). This means it doesn’t hold moisture very well, which is why I’ve got Douglas fir. It also means apparently that fire ants love it, which is why I’m in incredible pain.