Calendar of Events
Officers
Archives
Links
Photo Albums
Name That Spot !
What's New?
For more information
on the
Kennebecasis Naturalist
Society
contact:
Chairperson:
Carol MacFarlane at
433-4421
Last updated
Jan. 11, 2000
by
Brian Elliot
Comments and/or questions?
Web Master
The Weatherstick
by Nelson Poirier and Ajo Wissink
editors note: This was another interesting discussion on the internet. I have one of these weather sticks and was always curious about how it works. As many may be aware, there is a small wooden branch that is available on the market to attach to an outdoor wall to predict weather. I suspect it detects moisture levels and works in this way. Am surprised at the accuracy of this little gismo, but being of a typical inquisitive naturalist mind, would very much like to know what tree this branch comes from, if it grows locally and if so how is it best prepared for use. Am surprised to have never encountered this is nature literature. Would sure appreciate any info from my nature kin out there in cyberspace.
From: Nelson Poirier, Shediac Bridge, NB
Apparently the under and upper sides of the branch expand at different rates when water is absorbed. I don't know which tree is used for the weather sticks that are sold in some stores, but I have found that it works well with spruce. Cut the top of a small dead one and leave one side branch. You see the same thing happening with pine cones: closing in damp weather and opening when it is dry.
Yesterday I went out in my backyard and collected samples of White Spruce, Balsam Fir, White Pine and Jack Pine. I stuck these, for about 15 minutes, at low heat, in the oven of the kitchen range, recorded the results and then put them in a plastic bag with some wet tissues.
This afternoon I took them out and noticed that all 4 species had changed shape. The 2 pines not very much, but the spruce and fir were really spectacular and both at about the same rate. The side branches move up when it is wet and down when it is dry. In fact, this is the same kind of movement that opens the cones in dry weather, to release the seeds, and closes the cones in damp weather. It is obvious why that happens with the cones, but why is it also happening with the branches? What would be the advantage? Someone out there with a theory? Also, the difference in expansion rate between upper and lower sides of the branches was sometimes so great that in the samples of spruce and fir the orientation of the curve was reversed: in the dry stage the convex side pointed upwards and in the wet stage the convex side pointed downwards.
From: Ajo Wissink, Rosevale, NB