Sprucing up the hills

The Fled overflies as I reel it in.
The Fled overflies as I reel it in.
It has been 14 years since we set up our first study plots south of the Alaska Range. I just returned to Fairbanks from a week-long trip to re-census the plots located above the upper forest limit at the Canyon Creek and Monahan Flats sites. There were a few scattered spruce trees and a total of a few dozen spruce seedlings marked with numbered tags in the quarter-hectare plots in 1998. The trees have not changed much, and only 8 to 10% of the seedlings have died. The surprise was the number of new spruce seedlings that have established in 14 years.
The NIR modified and normal A495 cameras with AuRiCo controller. Synchronous, vertical photos were taken every 16 seconds.
Seedling density increased by a factor of 2.9x at Canyon Creek and 2.2x at Monahan Flats. The similarity between the two sites suggests that the seedling invasion may be widespread. These seedlings have a lot to endure before they become trees, but if similar numbers of seedlings continue to establish and many of them become trees, these plots will no longer be above treeline in 50 years.

I was able to get some aerial photos of most of the plots after I had marked each seedling with pink flagging. I flew a dual camera KAP rig with normal and infrared-modified cameras lofted by a kite. I will be experimenting with false color IR (NRG) and NDVI images which can be created with information from both cameras.

The KAP rig under the Fled kite.
The KAP rig under the Fled kite.
The normal color images will also be useful, especially in the last plot which had more seedlings than any other, and was sampled after I had run out of metal tags (who knew I would need 160 tags?). I have a crude hand drawn map of the seedlings but also a vertical “ortho” photo of the plot with flagging on each seedling. With an annotated version of this photo in hand it should be straightforward to put the correct tags on the seedlings next time. [UPDATE: some progress on the plot maps is described here.]

Part of Monahan Flats plot 1
Plot MA1 with the spruce seedlings marked. Several vertical shots will be stitched together to cover the whole plot.

Below is a gigapan taken from the 1998 campsite above the Canyon Creek site. There were many memories there of the awesome field crew that established these plots. A better view and more info is at gigapan.com.

Here is a panorama at Photosynth of the Monahan Flats site. The snapshots have captions. Can also be viewed at Photosynth.

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