• Alaska Climate Research Using Tree Phenology

    Sponsored by

    Society for Science & the Public Fellowship Grant

    matt instructionclinometertree plugleaf idwoods

    Located at latitude 61, Alaska’s Matanuska-Susitna Borough is the fastest growing area in Alaska.  With growth comes impact to the environment.  Thus, our first objective will be to teach high school students from Career & Technical High School to work with local organizations and scientists to conduct a field based research project through inquiry to develop baseline data on the emergence of tree buds as a way to monitor climate change.  Students will be collecting data from birch, willow, cottonwood and alder trees.  Buds from these trees within the sampling plots will be collected from the area surrounding the school.  The length of the buds, moisture content, tree height, diameter, circumference, and age of each sample tree will be recorded.  Data and results will then be shared with local organizations like the State of Alaska, Forestry Division, and The Wasilla Soil and Water Conservation District, as well as national organizations like The GLOBE Project and Budburst.org 

    By completing these activities our second objective, getting the students into the field working as cooperative groups that are energized and engaged into a meaningful science/math project that will increase their interest in a science career, while improving their environmental awareness and test performance will be met.
    This project has been funded by a $10,790 grant (2009), $5,000 grant (2010) from Toshiba and $10,000 grant from Toyota and (2011-2014) $8,500 grant each year from Society for Science & the Public Fellowship grant.  This project consists of four parts:
    period3    period 5

    Part 1 - Documentation of Budburst:

    2009 -   April 25th - Palmer
                  April 27th - CTHS
    2010 -    April 21st - Palmer
                   April 26th - CTHS
    2011 -    April 26th - Palmer
                   April 27th - CTHS
    2012 -    April 23rd - Palmer
                   April 25-27th - CTHS
    2013-     May 9th - Palmer
                   May 11th - CTHS
    2014 -    April 21st - Palmer
                  April 22nd - CTHS - Birch only
          2015 -    April 24th - CTHS
          2016 -    April 2nd - Palmer
                        April 3rd - CTHS  
          2017    April 22nd - Palmer -- Earth Day
                      April 22nd - CTHS   
    All the data were recorded by the students and entered on the www.globe.gov under the phenology section.

    Part 2 - Percent of moisture in tree buds: Below is the process and results of this project.


    Problem:  Can moisture in tree buds be used to determine when budburst will occur.


    Hypothesis: Bud moisture can be used accurately to predict when budburst will occur.



    • Scissors
    • 2 plastic bags
    • 2 paper bags
    • GPS
    • Scale (must go to .001g)
    • Drying oven
    • Budburst data sheet
    • Computer with internet access
    • Thermometer
    • Weather station/ access to temperature, air pressure, cloud cover readings
    • Ruler
    • Budburst protocol data sheet
    • Surveyors tape
    • Clipboard

    Experimental procedure:

    1)      Gather all the equipment listed above

    2)      Go out to tree test sites  around Mat-Su Career & Technical High school and find two trees with at least ten buds on each tree

    3)      Using the scissors cut ten buds off of the first tree and store them in the first plastic bag

    4)      Repeat step 4 for the second tree and store those buds in the second plastic bag

    5)      Take the GPS reading of the location of both of your trees and write them down on the data sheet

          6)  Take the bags inside and keeping them separate remove the buds from the plastic bags
          7)  Using a milligram electronic scale weigh the buds from the first tree all together

    8)  Record the data on your data sheet.

    9)  Take the buds off of your scale and put them into one of the paper bags

    10)  Label that paper bag with a 1 on it for tree 1.

    11)  Repeat steps 7-11 with the buds from the second tree labeling this paper bag with a 2, for tree 2

    12)  Put both paper bags in the drying oven at 140 F
    13) After 48 hours remove tree buds from drying oven.

          14)  Weight the buds from tree one and record it on the data sheet


    15)  Throw the buds from tree one away

    16)  Weigh the buds from tree two and record them on the data sheet
    17) Determine the amount of moisture in the buds and record data

    18)  Repeat steps 1-17 two times per week  around CTHS until the buds burst


    (Too large to put on the web)

    2009 - 54% moisture content in Alaska Paper Birch

    2010 - 48% moisture content in Alaska Paper Birch

    2011 - 49.16% moisture content in Alaska Paper Birch

          2012 - 59.52% moisture content in Alaska Paper Birch - *** Record Year for snow Fall****

    I believe that the moisture in tree buds is a good indicator of when the the bud will emerge.  From the first three years our data indicates that the trees that were tested need to have a moisture content between 48 and 60% before the bud will emerge.  We did find that environmental temperature, moisture, age of tree and location of tree played a role on when the tree would reach that magic number needed for the bud to emerge.  Several issues have arisen over the years (moose eating available tree buds, size of tree bud, temperature and length that the buds stay in the drying oven)which allowed us modifying our experiment giving us more accurate data.
    Part 3 - Green-up - the documentation of the time it takes the leaf to reach full size.
    measuring tree bud  leaf measurements measuring buds 2 green up
    Students measured the length (mm) of the first four leaves off of one branch, from a tree within their test sites.  Students selected two trees from CTHS test site.  Students began taking measurements from the time of bud emergence until the third week in May (end of school). Unfortunately, since school ends around May 20th students were able only to document about 60% of the actual growth of the leaves.  All the data that was collected was entered on www.globe.gov website under the phenology section.


    Part 4 How much sugar is in birch sap?


    Students tested 20 trees yearly around CTHS and have found that all the Alaska Paper Birch trees have a sugar content of .8 to 2.5%.

    measuring birch sugar
    Check out the Frontiersman article about this project
    Special Thanks To
    Dr. Elna Sparrow and Martha Kopplin GLOBE Coordinators @ University of Alaska Fairbanks
    Matt Weaver, State of Alaska, Forestry Division
    Toshiba America Foundation
    Toyota TAPESTRY




Last Modified on April 24, 2017