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.
- 2 plastic bags
- 2 paper bags
- Scale (must go to .001g)
- Drying oven
- Budburst data sheet
- Computer with internet access
- Weather station/ access to temperature, air pressure, cloud cover readings
- Budburst protocol data sheet
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.
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%.
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