We spent a day gathering height and circumference measurements of Douglas Fir trees at three different localities along the White River valley near Mt. Rainier.  Heights were measured using an inclinometer and tape measure, plus some trigonometry.  The following class period was spent analyzing the data to understand more about how Douglas Fir trees growth with time.

This first group of photos is from the youngest forest, 10-15 years old,
just off of Highway 410.  Many former clearcuts in this area with closely spaced trees.
 

Ilona, April and Ed measuring three different Douglas Fir trees.  Ilona is about to measure circumference,
April is measuring horizontal distance, and Ed is measuring angle to the treetop.
 
 

Kirk measures the horizontal distance to the tree while Adam (back to camera) records the data.
 

Measuring the inclination to the top of the trees.  Tim, Raven, Megan and Michelle working the inclinometers.
 

Discussing the results.  Raven, Joe (instructor), Kevin, Robert, Megan and Violeta.
 

This area near the McCullough Seed Tree farm
contains mature Douglas firs (75-100 years old?).
No stumps, never cut....
 

April, Sern, Kim and Ed work the tapes.  Fiberglass measuring tapes were provided.
 

Christian measures while Lindell records.  The understory in the left foreground is salal and oregon grape.
 

Federation Forest State Park along Highway 410.
This old growth area contains trees up to 300 years old.
The area may have been scoured during a 300 year old lahar (volcanic mudflow).
 

Tammy and Piper measure the circumference of a big tree at the parking lot.
 

Sern and Raimol compare notes.  Notice the lack of sunlight in this old growth forest.
 

Kim uses the inclinometer.  Best results when the angle of elevation is around 45 degrees or less.
The inclinometers are a modest expense that really improves the accuracy of height measurement.
 

An old tree next to the highway had been cut, providing an opportunity to measure circumference
and age using the tree rings.  Kevin, Robert, Christian and Lindell.
 

Push pins were provided to make the counting easier; one pin every 20 rings.  Noah, Anh, Walter and Jonathan's hands.
This tree was approximately 300 years old when it was cut.
 

Students then measure the radius to calculate the circumference.  Walter, Tomo, Jonathan and Anh.
 
 

The Dalles Campground along Highway 410 has one monster tree,
plus many 300+ year old Douglas Firs.
 

A 700 year old Douglas fir in the Dalles campground along Hiway 410.  Note fire marks.
 

Piper, Beth and Asta measure the circumference of the 700 year old Douglas Fir.
Notice the deep grooves in the bark characteristic of Douglas fir.
Western red cedar to the upper left and hemlock to the right.
 

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