Tree measurements at Reserve West beat the arrival of snow – again

Permanent marker post at Reserve West, driven down into the ground when a large spruce snag killed by the 1983 Rosie Creek Fire fell on it.

Completion of the 2011 Reserve West white spruce measurements, Oct. 5. (left to right, Randy Peterson, Glenn Juday, David Spencer).

David Spencer arriving at Reserve West hectare reference stand, in shirtsleeve weather on Sept. 27, 2011.

Where were you in the fall of 1988? Every fall since then? SNRAS Professor of Forest Ecology Glenn Juday can answer that question for these past 24 years. He and his technicians, graduate students, postdocs, and undergraduate students have measured the growth and survival of all white spruce trees in a hectare (2.47 acre) forest plot. The annual exercise takes place at Bonanza Creek Experimental Forest (BCEF) 20 miles southwest of Fairbanks.

This long-running study involves the measurement of about 2,200 trees that have been mapped at a study site Reserve West, one of six BCEF locations with hectare-scale plots called “hectare reference stands.” An article describing the BCEF forest monitoring system and history at BCEF reference stands has been accepted for a publication on long term ecological and silvicultural sites in North America, which will be published by the Global Institute for Sustainable Forestry and the Yale University School of Forestry and Environmental Studies.

Reserve West was burned in May 1983 during the Rosie Creek Fire (see: Juday, Glenn P. 1985. The Rosie Creek Fire. Agroborealis 17(1): 11-20.). The Alaska Legislature funded the Rosie Creek Fire Research Project from 1983 to 1986. One of the studies involved establishing hectare reference plots in the three forest types most important for wood production – white spruce dominated, aspen dominated, and Alaska birch dominated stands, both burned by the Rosie Creek Fire and not burned. All trees in the six stands were mapped and measured starting in 1988, and the Reserve West hectare (burned white spruce) has been measured each year since (See: “Watching the Trees Return” Agroborealis 36: 2, (Winter 2004/2005) Pp 8-10).

Reserve West tree measurements need to be made after the growth season is completed but before the arrival of snow. This year’s effort started in the last week of August, paused for other work, and then was completed by Oct. 5. Crew members included David Spencer (Tree Ring lab technician and former UAF NRM undergraduate), Tom Grant (post-doc, and instructor in NRM 101), Randy Peterson (M.S. 2011 under Dr. Jingjing Liang). Eric Merrill, NRM undergraduate participated several days and is using data for his senior thesis project. Previous participants include Kimberley Maher (Ph.D. candidate), Emily Sousa (Geography M.S. student), Steve Winslow (NRM B.S. and M.S.), Scott Sink (NRM M.S.), and Robert Solomon (research technician).

Weather during the measurement season was unusually mild. During most years some snow falls on the measurement crew. In 2011 no measurable snowfall occurred for the first time in the 106-year Fairbanks weather record. Nearly all days the crew worked without jackets – another first. On a couple of days a pack of wolves gave an afternoon howl a couple of miles away, and grouse drumming provided a steady accompaniment to the work.

For the first time, some of the tallest trees exceeded the height of the extendable rangepole (765 cm or 25 ft) used to measure them, so a laser height measurement device (hypsometer) with a tripod mount was used. To get repeatable tree diameter measurements it’s important to measure the exact same place on the tree from year to year. In past years the crew at Reserve West has used a crayon marker, but it was causing some damage to young trees. This year a new paint applicator was used, and it seemed to work well. Future updates may give an idea of how the paint holds up. Who knows; maybe for years to come.

Tom Grant, measuring 2011 height growth with a meter stick.