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Continental N Day 2: Arkansas and Mississippi

Screen Shot 2014-03-15 at 9.19.51 PMStates Sampled: Texas, Louisiana, Arkansas, Mississippi
Trees Cored: 40
Total Mileage: ~1250
Total In-Car Hours: ~20

Today seemed to be the day in which things I never knew could happen while coring happened. We got cores stuck in all sorts of interesting ways, and I was peed on (yes, urinated upon – there is no more accurate way to describe this) by a tree.

But let me begin at the beginning.

Site 3: Simonson Biological Field Station, Arkansas
Since it’s the weekend, we didn’t see anyone at either site, and in both cases had to leave the car at a locked gate and hike into our site (I use the term ‘hike’ loosely). Coring was nearly uneventful at Simonson, except that one of the cores got stuck in the borer. We got the corer into the tree, but couldn’t even get the extractor into the corer to pull out the core. This happens sometimes, and is a bit of a pain, but a solvable problem. We pulled the corer out (with the core still inside) and finagled the core in every way possible. I even brought a narrow metal rod used for cleaning guns, which fits nicely into the core and thought I could use it to push the core out of the corer. I succeeded only in snapping the rod clean in two…. I’m not sure why this happened. Sometimes when it’s cold, cores will expand once removed from the tree, but it wasn’t cold, and expansion usually only occurs after you remove the core from the corer. I’m not totally sure how we’ll get it out of the corer, so for the meantime (potentially the rest of the trip), we are minus a corer.
In other news, Kendra had recommended I bring bike gloves because apparently all the cool dendro kids core with bike gloves to protect their palms. I brought a pair of Anthony’s weight lifting gloves, and they were surprisingly helpful! I think weight lifting gloves are way cooler than bike gloves, so maybe I’ll start a new dendro trend…
We also made friends with a dog that lived across the street from the station. I love dogs.

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Site 4: Ole Miss Field Station, Mississippi
Much like Simonson, this site would have been uneventful, if it weren’t for a couple super odd occurrences. First of all, we got another core stuck in a corer. But even more strangely, this one was poking out the end of the corer. In theory, when you core into a tree, the core stays in the center of the corer, and you use the extractor to pull it out. Sometimes, when that fails, the core just stays in the corer (see above), but I’ve never seen it get yanked out the end. I assume that it didn’t fully break off from the rest of the tree, and as I twisted off the corer, the core was pulled out from the middle. Fortunately, it was an oak (a hardwood), so I was able to yank it out of the corer. Still, weird.
But that was NOTHING compared to the next tree I cored. This was also an oak. I twisted the corer in like normal, and as I was about to reach for the extractor, IT PEED ON ME. I’m not joking – liquid water started pouring out of the corer (photos below). I’ve seen trees out-gas if the center is rotted (it’s kind of cute – sounds halfway between moaning and farting and is very un-treelike, trees generally being stately and majestic individuals). I also know that you can tap into trees (like maples) and extract sap. Sap is thick and slowly oozes out of a tree over days/weeks/months at a time. This was LIQUID water, POURING out of the tree. And it STANK. Emily (coring at the next tree) was at first amused by my shouts of “Ack! What is this!” and “Oh god, it smells!” and then eventually could smell it herself…. I waited for over a full minute and the stream never slowed. I finally worried about leaving the corer unmoving for much longer (at the risk of the tree sealing around it) and so just sucked it up and extracted the core and removed the corer, all within a stream of tree pee. I used two alcohol-based hand wipes, washed my hands four times, SHOWERED, and used scented hand lotion, and my hands still smell like tree pee. Also, the tree continued leaking (or whatever it should be called) for several minutes after I removed the core (see picture below). It was weird and disgusting, and I have no idea what caused it or if it affects the usability of the core. But ugh, it was gross.

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This is when your Garmin is no longer useful.

Our only real problems came from the driving itself. There was a ton of construction, so at one point, we tried to re-navigate on our own (sorry, Vicky), which went ok, but slowed us down (though probably less so than the construction). Fortunately, Emily is good with the road atlas. I can also say that there is at least one young and rather handsome state trooper with an endearing southern accent in Arkansas who is willing to let two young ladies go with just a warning and not a speeding ticket. How I came by that particular piece of information is not strictly relevant to this post… Regardless, today took longer than I expected, so we won’t be sleeping in as much tomorrow. I have tentatively promised Emily no more 4 am days, which I will try really hard to keep 🙂

Continental N Day 1: Texas and Louisiana

Screen Shot 2014-03-14 at 9.56.19 PMStates Sampled: Texas, Louisiana
Trees Cored: 20
Total Mileage: ~800
Total In-Car Hours: ~12.5

Emily and I successfully survived our first day of Continental N sampling! We spent last night with my parents in Hutchinson to knock off at least a couple hours of today’s long haul. Mom and Phaffs sent us off this morning at the crisp hour of 5 am with hugs and home-baked blueberry muffins 🙂

Site 1: Davy Crockett National Forest, Texas
We made it to DCNF in a little over 8 hours, thanks to Google Maps not accurately estimating the strength of my lead foot. We also made it to the Texas border with a quarter tank of gas, which bodes well for our gas efficiency. After a small kerfuffle with finding the area in which we were allowed to sample, we got ten good trees fairly easily. All were Pinus taeda (loblolly pine), which core fairly easily and smell *wonderful*. The site was recently burned, of which I was unaware – that’s not necessarily a problem, but this site will now be classified as one of our disturbance-impacted sites and not a strict natural abundance record.

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Site 2: Kisatchie National Forest, Louisiana
Though we’d already spent a significant amount of time in the car, the Louisiana site is only three hours away from the Texas site, so I tacked it on to today. Vicky (my Garmin) started making some interesting choices with directions, culminating in what I will generously call a road that was kind of paved, in some places…. It’s not totally her fault – when you’re in the boonies of one state and want to get to the boonies of the neighboring state, there’s generally not a major highway between the two. Regardless, I may need to take a more active management role in Vicky’s decision-making. This stand was more diverse than the Texas stand, though still including Pinus taeda. We took some of those, as well as some Quercus velutina (black oak) and a couple of an as-yet unidentified tree. It’s not 100% clear what this tree is, and we were running out of daylight for field ID, so I took some photos and a couple litter samples and we’ll do some more in-depth identifying when we have time later. In the meantime, feel free to leave some suggestions on what species you think it is!
Incidentally, we almost lost the corer in this tree as well. It was not actually due to lackadaisical removal of the corer, which is usually how that happens (the tree can seal wounds so quickly that it can ‘trap’ the corer in place if you don’t remove it fast enough). Once inside the tree, the core somehow lost traction and was just spinning in the hole instead of twisting out. So long as you can keep it moving, you always have hope, so we just kept tugging and twisting, and with our combined upper body strength (and perhaps a foot braced against the tree trunk), we managed to yank it back to where the threads could gain traction and twist it all the way out. But whew – it was close 🙂

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We finished at Kisatchie with a bit of daylight left, so we decided to make it an extra hour up to Shreveport, LA to spend the night. This means we are technically AHEAD OF SCHEDULE. I am nowhere near naive enough to believe this trend will continue, but it’s nice to have our first day (which was also one of the longest) not set us behind.

We’re now holed up in a Comfort Inn. We are showered (smelling *much* better than we did an hour ago) and looking forward to a hot breakfast in the morning! The plan for tomorrow is to head up to Simonson Biological Field Station near Bismark, AR and then over to the UMiss Field Station near Abbeville, MS. Total driving time should be closer to 7 or 8 hours compared to today’s 12+, so we get to sleep in till SEVEN am!! Look out for some well-rested, well-fed, possibly butt- and bicep-sore, tree-coring MACHINES tomorrow!

Continental N: The Final Countdown

The Continental N sampling trip is fast approaching! On March 14th, Emily Sutton and I will set out for our 10-day, 14-state, 140-tree road trip.

We had a rather last minute change in strategy. Originally, I had planned on doing the northern loop (NE, SD, ND, IA) first, then proceeding to the southern loop. We decided to reverse this order partially to give the northern states an extra week for weather purposes (no Snowmaggedons, please!) but mostly to increase the effectiveness of the trip. Namely, if we get too delayed, we will have to cut the trip short after one loop. The southern loop constitutes more sampling locations and would therefor be the most valuable loop. If we have to cut the trip short, I can complete the northern loop over a weekend sometime later in the spring/summer. Depending on the weather, we may delay the northern loop regardless of how efficient we are with the southern loop.


Our final itinerary. Different colored lines are different days worth of driving, sampling dots are NADP stations (blue), OBFS (red), both (green) or neither (yellow).

Problems that have already been solved:

1) Hiring A Field Assistant: Emily Sutton, a junior at KSU double majoring in Biology and Anthropology, will be accompanying me on the trip. We drove out to Konza yesterday for a ‘dry run’ with Kendra (see photos below). Kendra and I were stressing the importance of quickly removing the corer from the tree, as trees can quickly seal around the corer and lock it into the tree. I have nearly lost a corer this way, and Kendra actually had gotten one permanently stuck once. Ironically, the practice tree we chose had apparently been previously sampled, as there was a 5 mm borer still stuck in the side!


Emily Sutton coring a Konza burr oak (left) and a stuck corer left by a previous researcher in the base of the tree (right)

2) Permits and Permissions: all sites have been approved by a park biologist or research coordinator. Additionally, I have notified all sites of the exact sampling locations and addressed logistics of access (ex. is there a locked gate?). For each site, I have a little bundle that contains a sampling sheet (for taking notes as we sample trees), a copy of the approved permit, and addresses/phone numbers for the site contact (see photo below). I’ve also listed out street addresses and phone numbers for nearby ranger stations, just in case.


Information bundles for each site, containing sample note sheets (on top) with detailed descriptions of the sampling location (lat/long, driving directions), contact person name and number, and approved permits.

Problems for which I am prepared:

1) Getting Lost: Many of our field sites are rather remote, and either do not have actual street addresses (like the NADP stations), or have addresses that even Google Maps does not recognize (like forest service or county roads). We will have a Garmin, handheld GPS units, a 2014 road atlas, Google Map screenshots of our sampling locations at various scales, and our smart phones. I have even put little stickers over the sampling locations in the road atlas (see photo below).


Bankhead National Forest, Alabama. Our sampling site will be in the Sipsey Wilderness just north of Double Springs, AL to the west of Highway 33.

2) Getting Delayed: I have (intentionally) planned this to be a rather ambitious trip. I would rather have planned too much work and not have time to get through all of the sites than plan too few and have extra time which I could have used to sample additional sites if we had permission. It is more important that we have good samples from the sites we do visit than get sloppy samples from a lot of sites (ie. we want quality over quantity here). Consequently, we may get significantly delayed.  This is why Missouri has been dubbed ‘the ripcord.’ If we are significantly delayed by the time we get to the Missouri sampling site, we will bail on the northern loop and come home. If we think we have time (and weather permits) for the northern loop, we will forgo the ripcord and continue on.

3) Running Out of Daylight: in some cases, we will have ~12 hours of driving in a single day, with sampling halfway through and at the end of the day. That means the evening site will almost certainly be reached after the sun has set. I have brought several flashlights, including a large lantern-style one, and I have two headlamps we can use to keep our hands free. I will avoid sampling at night if we can (it’s more dangerous logistically, and will also be more difficult to ID trees, etc) but am prepared to do so on the couple of days where it is unavoidable.

4) Equipment Failure: I am taking backups of everything; multiple GPS units, every corer the PaleoLab owns, and multiple flashlights/writing utensils/maps. I have extra batteries for everything that needs batteries.

Problems for which you can’t really prepare:

1) Accidents: We’ll have a first aid kit and I’m trained in first aid and CPR, but I’m mostly just crossing my fingers that we don’t have any injuries or illnesses to deal with. Ditto for vehicular breakdowns.

2) The Soul-Crushing Boredom: I’ll bring some trivia cards, and some CDs, maybe a book on tape. Let’s just hope Emily enjoys playing 20 questions. For 12 hours a day. For 10 straight days…

3) The X-Factor: Things always go wrong in field work. I mean, really – things ALWAYS go wrong in field work. I can run scenarios through my head for weeks and I will not think of the one minute thing that could unravel the whole trip. But when it happens, you just have to be adaptable, remain calm, survey your options, and make the best judgement you can.

And remember – it’s FUN! 🙂

I Got 99 Problems, But a Permit Ain’t One

I considered titling this entry ‘How to Plan Your Field Research’ but let’s be honest, when is it a bad choice to make a Jay-Z reference? Or, if you’re like me and prefer the Hugo version, a reference to a Thai bluegrass Jay-Z reinterpretation (yeah, you read that right).

Anyway, the title is aptly chosen as field work constitutes at least 99 problems – and that’s just in the planning stages. Let’s organize them into chronological order during the planning process:

1) Picking a field site and sampling location

For the Continental N project, we want sample locations in all of the lower 48 states. Many, we have been able to ask, beg, wheedle, cajole and nag our Novus network, and personal contacts to sample for us. That still leaves us ~30 states to sample ourselves, mostly throughout the upper midwest and deep south. For each state, I first looked at the Organization of Biological Field Stations and National Atmospheric Deposition Program stations, to see if that state had any. Some states also had Long Term Ecological Research stations. If possible, it’s nice to sample in/near these stations, so that we can link our tree ring data to near-by measurements of environmental factors (temp, precip) or atmospheric nitrogen deposition. Starting with these sites is also beneficial because they usually list contact personnel for research permissions, which makes the job of finding whom to contact for approval much easier.

But sometimes, there’s no LTER, and no OBFS sites in a state (all, though, have NADP). Even when OBFS and NADP sites exist, sometimes they are located in urban centers, or in agricultural land (which are no good for us). So, for a few states, I had to play ‘find a publicly owned stand of trees’ on Google maps. This usually brought me to a national forest, or wildlife refuge, etc. Again, they usually have decent websites with contact info so I can at least get the process started.

I like to color-code things based on how far along they are in the process. Generally, green means go, while various shades of orange, yellow or red indicate various issues yet to be resolved

I like to color-code things based on how far along they are in the process. Generally, green means go, while shades of orange, yellow or red indicate various issues yet to be resolved

2) Start the awkward phone calls

Unless you have the name of the actual person in charge of research permitting, a cold email (particularly to a general informational email like <park>@<governmentagency>.gov) is likely to get ignored. I’ve found it’s always good to call, it somehow is more likely to get a response, even in this day of technological advancement. Repeated phone calls to strangers get awkward fast. Particularly when you usually start with a general informational line (especially for the national forests, etc) and the first three people you talk to will seem to have never heard of research, or trees, or Kansas. Be prepared for everyone to get confused, yourself included. But stick with it – if you’re willing to repeat yourself, and answer any seemingly odd question that is asked, you’ll make it through to the right person, eventually.

3) Get the Permit

This stage of the process varies considerably. Some people will just want to know what you’re sampling (often, as soon as I say ‘trees’ they are less worried – animal research requires many more hoops), other times, they have a long and complex online permitting system where you will have to document the number of oxygen molecules you plan to breathe at the field site (that’s only partly a joke). On opposite ends of the spectrum, I had one research station literally just say “That sounds cool, I don’t need a proposal, just call me before you get here, so I know to open the gate” while on the other end, the National Park Service has a formal online portal for requesting permission at any of their properties. The Forest Service also has a fairly detailed survey, even for just a special use (and not a formal long-term research) permit. These agencies want to know exactly what you will be sampling, how you plan to access the site, the anticipated effects on the study organisms and the surrounding habitat, your intended use of the data, and the history and anticipated future of the full project.

4)Oh $#!* – I need money!

Oh, yeah – sorry. Having an awesome idea doesn’t necessarily mean you have the money to do it (let’s not even talk about NSF funding rates right now). It’s at about this stage when you realize all of your work thus far is moot if you have no money to a) get to the sites, and b) run any analyses once you come back. The trip I’m planning (outlined below) will cost just under $3,000 in gas and lodging, for which I was fortunate to get money from the Academic Excellence Fund at K-State.

5) The Final (Logistics) Frontier

So now, I have the permits ALL approved! And, I have the money to pay for the trip! Now is actually the most complicated part – logistically organizing a large field-sampling trip. As you see in the map below, I’ll be sampling in 14 states. As always, my color coding means something. Blue tags are NADP sites, red are OBFS, green are members of both programs, and yellow are neither. Each colored line represents one day’s travel (averaging ~8 hours of driving per day). We’ll start in Manhattan, go north through NE, SD, ND, then east a bit and down through IA, MO, AR, east through TN and NC, then back west through SC, GA, AL, MS, LA and TX, then back home to Kansas. Nearly every day consists of a morning drive, sampling in one location, then continuing on to a second location where we still say the night. I’m not sampling in Minnesota, Oklahoma, or Kansas because we already have data from those states.

For each end day site, we’ll need a place to stay. I’m hesitant to book hotels, because if we get behind, all the reservations will be off. Instead, my priority list for housing is 1) at the research station where we sample, 2) friends/family, 3) hotels, likely not reserved in advance. That last makes me nervous, because I’m anal retentive, but people do it all the time and it seems to work out ok. The places we’ll be going are not generally spring break hot spots (woo hoo, Big Springs Fish Hatchery, here we come!), so I don’t anticipate much trouble finding open hotels.

The Plan

The Plan

So what’s left to do? Looks all put together and ready to hit right? Well, mostly. I still need a field assistant. Since this trip will be over K-State’s spring break, it may be hard to convince a student to spend their *entire* spring break in a car with yours truly. I’m debating my options on this – we could do an open search, or try to recruit someone based on a recommendation.

More importantly, you have to have several back-up plans. Things *always* go wrong in field work. I’ll be going in March, so weather may be a problem. At the very least, things often take longer than you expect. Since I’m teaching a class in the spring, I’m on a tight timeline and can’t get afford to get delayed. I’ve built in a ‘lazy day’ (from Arkansas to Tennessee) where I can make up some time if I get behind. I’ve also scheduled this as a 10-day trip, but I have 11 days between my teaching days, so I can budget it an extra day if necessary. But if numerous locations prove problematic, I have to be careful to not get too far behind. This is where an assistant will be especially handy. If we have to drive through the night at any point, we’ll need to trade off for sleeping purposes.

This where you just remind yourself that field work is an *adventure!* and no matter what happens, it’ll at least make a funny story later.

Check back here starting March 14th for real-time updates on the trip!!!

Continental N Wood Processing Begins!

As you can see on my Current Research page, Kendra McLauchlan and I have been developing a collection of tree-ring chronologies throughout the entire contiguous United States (and maybe Alaska, if we’re feeling ambitious).

    Continental N sampling locations. Green = data in hand, Yellow = sampling in progress, Red = approvals for sampling in progress

Continental N sampling locations. Green = data in hand, Yellow = sampling in progress, Red = approvals for sampling in progress

As you can see in the map, we currently have 9 sampling locations representing 7 states (CA, CO, KS, OK, MN, IN, NH), shown in green. An additional 12 states are currently being sampled by Novus RCN collaborators (OR, ID, WY, UT, NM, KY, WV, OH, NJ, NY, VT, FL) and are shown in yellow. The red dots represent locations where I am currently in the process of obtaining permission to sample, which represent 14 more states (NE, SD, ND, IA, MO, AR, TX, LA, TN, MS, AL, GA, NC, SC). Once all these regions are sampled, we will have a grand total of 33 states out of the anticipated 48, nearly 70% of our goal. Requests are out to Novus participants and Kendra/my personal networks to fill in the remaining 15 states.

The green locations, representing data currently in hand are datasets that are already published (see Poulson et al 1995, McLauchlan et al 2007, McLauchlan and Craine 2012, Wolfe et al 2013), or were collected with the intent to publish, but not yet having done so. These are easy to work with as all the hard (and expensive) work has already been done! In these cases, I simply receive a data file of δ15N values which I format to fit out meta data file.

The yellow locations primarily represent places where collaborators have agreed to sample on our behalf and send us tree cores. In these cases, Kendra and I will process and run the data ourselves. The process (seen in the photos below) consists of sanding a core to clarify the rings, imaging the core in order to electronically measure ring widths, splitting the core so each ring is separated from the others, then weighing out the appropriate amount of tissue for N-isotope analysis and wrapping it in a tiny tin-foil capsule to aid in combustion in the mass spectrometer.

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This is where things get a bit tricky. Cores are small (the ones pictured above are 3-4 mm wide), but otherwise easy to use. Cores naturally split apart at the ring boundary (since the ‘ring’ you see is the result of denser tissue at the end of the growing season), and so splitting rings apart from cores is speedy and rather painless. The down side though is that their tiny size and rather fragile nature means they sometimes break easily, which can cause problems if sections are lost or mis-ordered when split. Tininess also means that narrow rings will not provide enough tissue to run N-isotope analysis (which requires 10-30 mg of tissue), so we will not be able to sample at an annual resolution.

Cross-sections (also known as ‘cookies’) are easier in that they provide ample amounts of tissue, and having the whole cross-section can aid in the identification of false rings (the appearance of a ring formed during the growing season, i.e. what looks like two rings is actually one growing season) and missing or locally absent rings (years in which a ring was not formed at all, or only formed in certain parts of the trunk, and therefore not visible across the entire cross-section). False and missing rings can seriously hinder cross-dating of ring chronologies, where a calendar year is assigned to each ring, so having a full cross-section can be very beneficial. The down side is that their large size (the ones pictured from Alaska are nearly a foot across and several inches thick) make it difficult to split tissue from each ring. Splitting rings from cookies often requires a hammer and fine-edged chisel to pry tissue apart.

You’ll also notice in the photos above that trees of the same species, living in the same region (those pictured being Pinus rigida from New Jersey), can be very different in appearance. In some, the ring boundaries are extremely faint. In others, they are very dark and contain wide late wood bands (the light portion of the ring is the early wood, laid down first in the growing season, while the rest is termed late wood), while others are very narrow. This variability is why the ratio of early- to late-wood in a chronology is a common dendrochronological metric. One core, which covered the entire cross-section of the tree shows much wider ring widths on one side of the center than the other. This pattern indicates the tree was not growing straight up, but leaning to the narrower-ringed side. Additional tissue is laid down on the ‘back’ side of the tree to balance out it’s weight.

Honestly, those differences are part of why I love dendro work. Every time I sand a new core, I don’t know what I’ll find – wide rings or narrow? Dark/obvious boundaries or very faint? Bright orange heartwood or pale tan? What drives these differences? In fact, much of that is not known – particularly when the differences occur within a species, in a small geographic range.

On the flip side, sometimes interesting patterns are visible within a group of trees. As I was processing the Idaho cores, I noticed they all had noticeably more narrow rings in the last ~50 years than the rest of their life span, and that almost every tree showed an unusually large ring in 2004. Why was 2004 an unusually productive year? The fact that it was every tree suggests a large-scale phenomenon. Perhaps it was unusually wet or warm – was 2004 an El Niño year? Does Idaho experience climatic differences in El Niño years? There have been many El Niño’s in the last ~50 years, why did they each not produce similar growth enhancements? If not a climatic factor, what else could have caused anomalously high growth in an isolated year? Why are the last several decades so low in productivity? Is this region experiencing some sort of stress or disturbance that is impacting tree health? Or perhaps this is a natural aging pattern in this species? I have tentative answers to most of these questions, but I look forward to diving into them in more detail. Each region will present it’s own set of similar questions, and hopefully, we can build some broad trends between sites.

I am currently working with samples mailed to us from Idaho, New Jersey, and Alaska and anticipating additional samples in the coming weeks from several more states. These will be the first data collected specifically for this project. We are also waiting to hear back on a funding request, which would enable the 10-day road trip to sample the fourteen red locations. Keep your fingers crossed!