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Trees among the tundra



TOOLIK FIELD STATION, ALASKA– Balsam poplar is the northern-most tree species in North America. In Arctic Alaska, it occurs sporadically in isolated stands often adjacent to perennial springs or on south-facing slopes. Join our field crew as we venture into one of these stands north of Toolik Lake. Our aim is to investigate a report from a colleague, Dr. John Hobbie (the former director of the Arctic LTER), of an errant spruce tree. Spruce, specifically white spruce, reaches its northern-most limit south of the Brooks Range. If a spruce tree is indeed present, it would be a significant find.



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3 Responses »

  1. Amy, you say you suspect this spruce seedling was planted? Aside from speculation as to motive and perpetrator, I wonder how one could more conclusively determine whether this tree germinated and established in-situ from a naturally distributed propagule, or whether (for whatever reason) someone transplanted it… E.g. on the already dead tree, I wonder if the tree rings would corroborate existence in-situ based on recent climate records for the site… I can’t myself think of any genetic means of testing… probably no good markers with high enough population-level resolution to suggest where it came from… and it seems at least probable that a human vector might have taken it from the same population (just south of the Brooks along the Dalton Highway) as would a natural vector… quite a little puzzle…

  2. Hi Ian,

    Indeed, it is a mystery!

    I don’t think there is a means to determine the origin of the spruce trees (genetic or otherwise). The disturbance at the base of each tree suggest both were recently planted. I didn’t mention in the video that I have visited this stand multiple times, including a late summer trip with Lisa Grubisha. We didn’t find Tricholoma populinum on that trip but Lee Taylor, accompanied by John and Erik Hobbie, did find it fruiting this year.

    Ohhhh, speculation as to motive and perpetrator - my hunch is it was planted by an employee at either the nearby Slope Mountain DOT or Alyeska’s Pump Station 2. This stand of poplars is within a 10 minute walk of the Haul Road and visible from the road. Treeline is an interesting phenomenon in northern Alaska, especially since one can essentially travel a latitudinal transect driving over Atigun Pass through ‘Gates of the Arctic’ (as Bob Marshall wrote). The trees are present on one side of the Brooks Range and then as one descends from the pass the landscape opens in an expanse of endless tundra to the coastal plain.

    Would you ever predict that someone would girdle the posted ‘Farthest North Spruce Tree’ on the Haul Road either?

    Thanks for your interest, Ian.

    Amy

  3. why are trees short in the tundra