Summer on a Shoestring

Roots, Rhizotrons, and Root Beer by Craig See
June 25, 2011, 10:39 pm
Filed under: Cooking in the white house, Fertilization, Minirhizotrons, Roots

When the last of our plots were fertilized at Hubbard and Jeffer’s Brooks, the shoestring crew let out a great collective sigh of relief.  Everyone was full of the sense of accomplishment that comes only after the most arduous of tasks has been completed. If the shakers of phosphorus had contained parmasian cheese instead, we could easily have coated what is left of Mannattan’s Little Italy.  If the nitrogen prills had been grains of dry sticky rice, we could have gotten most of Chinatown (These are metaphors that come to mind when you’re hungry, and caked in a layer of sweat, DEET, and monosodium phosphate with nothing to look forward to but a soggy PB&J.)  There was a sense that we had done the impossible.  And no one need worry about doing it again for six weeks!

Lin and Amos celbrating the end of fertilization

With fertilization Leviathan vanquished, everyone was looking forward to a few lab days.  The decision to postpone the summer inventory however, quickly turned this into a few weeks.  This year’s summer lab work consists mainly of sorting through root cores pulled from our plots last year.  Each core has been separated by depth (0-10 cm, and 10-30 cm).  It has been the crew’s charge to cleanly remove the tree roots from these piles of sand, rocks and humus, and sort them into two categories based on diameter.  As the vast majority of these roots fall into the “less than one millimeter diameter” class, the job has proved much more tedious than it sounds.  (Think thousands of very small, hair-like, fragile needles in a sometimes sandy, always thoroughly decomposed haystack.)  The blackfly bites on Lin’s arms had hardly finished scabbing over before she was asking about when she could get back out in the field.

Shinjini pickin’ roots

It was at this low point in moral that Neal came through like a glimmering patronus in the night with all seven Harry Potter novels on his computer.  Most of the crew was at least familiar with the storyline from the movies, but like most novels put on the big screen, the Hollywood portrayal is little more than a bastardized version of the real thing.  Harry’s adventures have helped everyone through what would have otherwise been another daunting task.  The sinister doings of Lord Voldemort’s Death Eaters have become a frequent topic of dinner conversation (along with nutrient co-limitation and resource optimization theory of course), and many a work day has continued past the normal 4:30 quit time in order to finish a root core (and a chapter).  And so the rest of June has passed with the crew huddled around a table in the lab like a bunch of eager and willing house elves peering over piles of roots on wet paper towels with forceps in hands.  As there is still the better part of a freezer full of root cores left, we have been recently assured that reinforcements will be helping us out from Tim Fahey’s lab at Cornell (similar to the arrival of the Order of the Phoenix swooping in to assist Dumbledore’s army in the Department of Mysteries).


The grad students, while often picking roots, have been struggling though trials and tribulations of their own.  Kikang has been having her own root problems, with the shorting out of her minirhizotron (a camera designed to gauge root growth at different soil depths over time).  The power cord on the camera had to be twisted back and forth with every measurement, until what was going on below ground was eventually illuminated on the laptop screen, and a photo series could be taken.  This could take several minutes, and worsened with each progressing site.  Eventually the poor machine gave out altogether.  She is currently en route to California for rehabilitation (the minirhizotron, not Kikang).  Meanwhile, Shinjini and Craig were trying to sort out inventory files and organize two years of litter collections in the lab, so that the occasional mutterings from behind their computer screens were the only thing punctuating the amazingly versatile voice of Jim Dale (narrator of the Harry Potter series).

The minirhizotron inaction: Lin twists the wire attempting get an image

Mealtimes at the white house have offered well needed and deserved repose from the daily goings on at Bartlett.  With a field crew hailing from places as far as China, Malaysia, Korea, India, and Hawaii, (as well as Oregon, Vermont, New York, and Minnesota), dinner has been a delightful mixture of pan-Asian, and US cuisine, replete with deserts.  Highlights have been some amazing fried rice and stir-fries, seaweed soups, curries, and every form of potatoes imaginable.  Russell, our newest addition from Hawaii, has promised us something with Spam soon, although Craig pointed out that to be fair, Spam is produced by the good people at Hormel located in the beautiful state of Minnesota.  In keeping with the recent theme of belowground biomass, all of the international students recently experienced root beer for the first time (in float form, of course).


In an attempt to cut down on the food budget, and be a little more sustainable, Lin and Craig have planted a small garden inthe back yard, although the only things that seem to be thriving thus far are the radishes.  The point has recently been raised that we still have a half ton of fertilizer on hand in the lab, and maybe we should do our own backyard experiment on nutrient co-limitation in a common root vegetable of the Brassicaceae family.  Unfortunately, our sample size is too small for a full factorial design.

the garden

The past week has included the added stress of handing in proposals for summer projects.  With the Hubbard Brook annual cooperator’s meeting less than two weeks away, projects are on everyone’s mind.  It is common knowledge that Matt Vadeboncoeur is an encyclopedia of all things relating to the Bartlett stands and the Shoestring project as a whole.  Since his arrival 48 hours ago, he has been bombarded with questions about the sites from every direction.  Undoubtedly Microsoft PowerPoint will be open on every laptop in Bartlett over the next week and a half.  Half of the crew will spend Monday through Thursday camping at Sleeper’s River measuring tree DBH’s during the day, and probably making slides while listening to Harry Potter in their tents at night.

Everyone is looking forward to the meeting with anticipation.  When it’s over we will be back in the field for the second fertilization, meticulously shaking out enough sugar to cover every cup coffee being slurped in SoHo, and throwing down enough rock salt to cover every square inch of the wound that is Wall Street.  Plans for a day long near-marathon (25 mile) hike across the peaks of the Presidential range are also in the works.  That’s all for now.


Playing God by Rebecca Walling
June 6, 2011, 10:29 am
Filed under: Fertilization

This week we jumped into fertilization.  My boyfriend Craig joined Ruth Yanai’s lab, and a month later I am in the middle of the White Mountains of New Hampshire ducking under saplings and climbing over granite boulders to spread phosphorus and nitrogen on the forest floor.

Last week, we picked up 300 lbs of ammonium nitrate and a half-ton of monosodium phosphate. Corrie and Craig worked out a measuring scheme to divide the nutrients into sandwich bags for spreading across each plot. We have 13 stands to subject to our treatment.  At each stand, we have four plots: one control (no fertilization), one nitrate addition, one phosphate addition, and one nitrate + phosphate addition. Another crew worked out a system to divide each plot into its 9 interior subplots, and subsequently divide each subplot into 4 rows.  Add in a 10 m buffer (divided into 16 buffer subplots), and you have a total of 650 bags of nitrate and 650 bags of phosphate.

The biggest challenge this week was deciding how to distribute the nutrients evenly over the forest floor.  The nitrate is pelletized into little “prills”, making it easier to spread.  It looks, for lack of a better analogy, like dippin’ dots – those overpriced “futuristic” cups of ice cream sold at theme parks.  Think of the challenge this way: we need to spread a cup of dippin’ dots over a 10 m x 10 m area.  That works out to about 7 dippin’ dots in an area the size of a dinner plate.  Tricky, but doable with practice.

Ammonium Nitrate dancing inside a bag

Spreading the phosphate presented a more difficult challenge.  It is a powder – about the same consistency as powdered sugar.  Imagine having to coat a donut that is about 11 m in diameter with half a cup of powdered sugar.  This metaphorical donut, of course, is pocked with large boulders, fallen trees, and is on a 30 degree slope up a mountain.  We thought of using a flour sifter.  Then a salt shaker.  Corrie saved the day by taking urine sample cups (presumably unused), cutting little circles of mesh screen, and using a rubber band to fasten the screens to the cups.

Monosodium Phosphate in a shaker

For the last two weeks, we have been perfecting our methodology.  A crew of 3 arrives at the field site.  Everyone walks up and down 2.5 m wide lanes in the control plot, making sure to impact the surface in the same way that our experimental plots are impacted.  The whole crew moves to the nitrogen plot.  Two people begin laying 10 m ropes out, marking each fertilization lane. A third person divides each bag of nitrogen into quarters.  We do the same thing nine times – move ropes, measure fertilizer, spread fertilizer, start again.  Once the interior of the plot has been fertilized, we move to the buffer zone.  Since the buffer need not be as precise as the measurement zone, we can spread an entire bag of fertilizer over one square, without subdividing it.  As I understand it, the reason we fertilize the buffer is that a large component of this study involves looking at tree response to fertilization.  Trees have root systems that can stretch beyond the measurement zone.  If they are on the edge of the plot, they take nutrients from not only the measurement zone, but also may draw nutrients from soil in the buffer zone.

Equipment in the field for measuring subplots and spreading fertilizer

And so the day goes – we finish the nitrogen plot, and move to the phosphorus plot.  We finish the phosphorus plot and move to the nitrogen + phosphorus plot.  Where we begin the whole process again: lay ropes, measure fertilizer, spread fertilizer.  It’s exhausting, mind-numbing work, tramping through the woods and spreading prills and powders. As tiresome as fertilization is, I can’t wait to hear about the results that come out of this research.  Nutrient addition is, in a way, the ultimate field manipulation.  As Ruth Yanai pointed out, it’s kind of like we’re playing God.  What could be more God-like to an ecosystems ecologist, after all, than altering the nutrient composition of the soil?

The first sprinkle of fertilizer is applied to a shoestring site by Ruth Yanai, after many years of preparation!



The fertilization countdown: 9 down, 4 to go.