Technician Claire Kubacki checks the health status of a large Douglas fir (Pseudotsuga menziesii) in FOREG-38

Claire Kubacki checking the number on the tree tag for a large Douglas fir (Pseudotsuga menziesii)

Technician Jack Shultz records data

Tagged trees in FOREG-38. The double tag indicates that the tree is part of the Big Plots study and the long-term Permanent Study Plot study, while the folded tag indicates the tree is dead

Technician Gio D'Innocente measures where to mark and measure the diameter of a big leaf maple (Acer macrophyllum)

Technicians working in a dense plot along Lookout Creek measuring a patch of red huckleberries (Vaccinium parvifolium) with calipers

Technician Gio D'Innocente uses calipers to measure the diameter of a red huckleberry (Vaccinium parvifolium)

Technicians search for missing tagged trees, which had been crushed by a large fallen Douglas fir (Pseudotsuga menziesii)

Technicians looking for missing tree tags, which were marked on trees five years prior and now have fallen on the ground

Technician Gio D'Innocente looking for missing tree tags for a hazelnut (Corylus cornuta var. californica) patch, which were marked on trees five years prior and now have fallen on the ground

Looking up into the canopy

The study plot (FOREG-38)

Technician Gio D'Innocente uses a diameter tape to measure a hazelnut tree (Corylus cornuta var. californica) in the plot

Tree tags that will be assigned to new trees as they "in-growth" into the plot when they become 1 cm in diameter

Large Douglas firs (Pseudotsuga menziesii) in FOREG-38

Technician Claire Kubacki measures the diameter of a western hemlock (Tsuga heterophylla) in FOREG-38

Technician Claire Kubacki measures the diameter of a vine maple tree (Acer circinatum), growing sideways, in FOREG-38

Vine maple (Acer circinatum) recently tagged and marked with markal paint stick to indicate it was measured and recorded

A tagged tree in FOREG-38

A tagged tree in FOREG-38 with technicians working in the plot

Measuring and recording tree diameter and health conditions

Technician Claire Kubacki measures and marks a vine maple (Acer circinatum)

Technician Claire Kubacki measures a small western hemlock (Tsuga heterophylla) in FOREG38

Tools of the trade--diameter tape, wire clippers, markal paint stick, calipers, compass, tree tags, wire

Technician Claire Kubacki uses calipers to measure the diameter of a small western hemlock (Tsuga heterophylla) in the study plot

Technician Amelia Leonard measures distance from an established tree to a tree that is being added to the study now that it is large enough

Technician Claire Kubacki measures the distance between trees

Technician Claire Kubacki measures the diameter of a large Douglas fir (Pseudotsuga menziesii) tree

A check at the base of a hemlock (Tsuga heterophylla) reveals rot inside the trunk

Technician Amelia Leonard records data

REU student Katie Hovind measures canopy cover over the streambed using a densiometer

REU student Katie Hovind, graduate student Maeve Bittle, and REU student Emma Cooper working in McCrae Creek at the HJA

REU student Katie Hovind measures canopy cover over the streambed using a densiometer

REU student Katie Hovind measures canopy cover over the streambed using a densiometer

REU student Emma Cooper inspects a rock with algae in McCrae Creek at the HJA

REU student Katie Hovind, graduate student Maeve Bittle, REU student Emma Cooper, and Professor Catalina Segura at McCrae Creek at the HJA

REU student Katie Hovind, graduate student Maeve Bittle, and REU student Emma Cooper ready for field work

Vials used to measure nutrient uptake will be placed in the stream (C for control, N for nitrate, and P for phosphate)

Study locations in streams at the HJA, which are in recently burned and unburned watersheds

REU student Katie Hovind attaches flagging to a tree to mark the location of the experiment along the stream

Graduate student Maeve Bittle secures vials that will measure nutrient updake in the stream.

REU students and graduate student Maeve Bittle employ sensors, tiles, and vials that will measure nutrient update, stream teampeature, and primary production.

REU students Katie Hovind and Emma Cooper working in Nostoc Creek in the HJA

REU students Katie Hovind and Emma Cooper working in Nostoc Creek in the HJA

Graduate student Maeve Bittle demonstrates a densiometer, which measures light incidence (canopy cover) above the streambed

REU student Emma Cooper measures canopy cover over the streambed using a densiometer

Vials (left), tiles (center), and a temperature sensor measure nutrient update, algal growth (primary productivity) and stream temperature

REU student Emma Cooper is studying discharge rates from stream culverts at the HJA

A section of Nostoc Creek being studied for stream nutrient and primary production changes following wildfire

OSU technician Sy Graber samples the stump in a recently burned area of the forest

Meg Krawchuk (left), Matthew Betts (center), and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Meg Krawchuk (left), Matthew Betts (center), and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Meg Krawchuk (left) and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Sampled tree stump with a fire scar and additional indicators of structural damage and branching.

Inspecting a sample of wood, showing a fire scar, taken from a tree stump

Inspecting a sample of wood, showing a fire scar, taken from a tree stump

OSU technicians Will Scypinski (left) and Amanda Brackett (right) use a chain saw to remove the top of an old stump

OSU technicians Will Scypinski (left) and Amanda Brackett (right) use a chain saw to remove the top of an old stump

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

Amanda Brackett (left) and Andrew Merschel (right) process the sample from a stump that displays a fire scar. The sample will be taken back to the OSU campus for processing and measuring.

Andrew Merschel cleans off a samples stump to reveal fire scars

Andrew Merschel points out the vertical fire scar--the dark vertical line of wood--in the sampled stump

A sampled stump and the tools of the trade -- chain saw, wedge, hatchet

Andrew Merschel makes final cuts on a sample to be taken back to the Tree Ring Lab on the OSU campus

Andrew Merschel makes final cuts on a sample to be taken back to the Tree Ring Lab on the OSU campus

OSU technician Zoe Beard with a sample taken from a stump, showing a fire scar

A hatchet is used to test if the wood of the stump is sound enough to warrant sampling.

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

Delicate samples are wrapped for transportation back to the lab on the OSU campus where they will be glued to boards for stability before analysis.

Ceanothus integerrimus grows profusely in an area that burned at high severity in the 2020 Holiday Farm Fire

Ceanothus integerrimus grows profusely in an area that burned at high severity in the 2020 Holiday Farm Fire

A sampled stump. The wedge, top left, will be taken back to the OSU Tree Ring Lab for processing and analysis to determine the year of the fire scar, which appears as a dark ring toward the center of the tree.

OSU Professor Meg Krawchuk looks over a sampled tree stump at the H.J. Andrews Experimental Forest

A sampled stump. The wedge, top left, will be taken back to the OSU Tree Ring Lab for processing and analysis to determine the year of the fire scar, which appears as a dark ring toward the center of the tree.

Fire history sampling crew from OSU: Will Scypinski, Amanda Brackett, Sy Graber

The top of a tree stump is cut and then removed, to expose the tree rings. The stump must be cut low to find solid wood, and scars appear more distinctly towards the base of the tree.

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

This sample reveals a fire scar, with a blackened tree ring bordered by resin and surrounded by curved growth rings of wood in subsequent years

Meg Krawchuk (left) looks on as Andrew Merschel points out a fire scar on a sample taken earlier in the day.

Western sword fern (Polystichum munitum) and Wood Sorrel (Oxalis oregana).

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

Amanda Brackett (left) and Andrew Merschel (right) process the sample from a stump that displays a fire scar. The sample will be taken back to the OSU campus for processing and measuring.

Andrew Merschel cleans off a samples stump to reveal fire scars

Andrew Merschel points out the vertical fire scar--the dark vertical line of wood--in the sampled stump

A sampled stump and the tools of the trade -- chain saw, wedge, hatchet

Andrew Merschel makes final cuts on a sample to be taken back to the Tree Ring Lab on the OSU campus

Andrew Merschel makes final cuts on a sample to be taken back to the Tree Ring Lab on the OSU campus

OSU technician Zoe Beard with a sample taken from a stump, showing a fire scar

A hatchet is used to test if the wood of the stump is sound enough to warrant sampling.

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

OSU technician Will Scypinski uses a chain saw to remove the top of a tree stump to reveal the growth rings of the wood, and possibly evidence of fire scars

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

Delicate samples are wrapped for transportation back to the lab on the OSU campus where they will be glued to boards for stability before analysis.

Ceanothus integerrimus grows profusely in an area that burned at high severity in the 2020 Holiday Farm Fire

Ceanothus integerrimus grows profusely in an area that burned at high severity in the 2020 Holiday Farm Fire

A sampled stump. The wedge, top left, will be taken back to the OSU Tree Ring Lab for processing and analysis to determine the year of the fire scar, which appears as a dark ring toward the center of the tree.

OSU Professor Meg Krawchuk looks over a sampled tree stump at the H.J. Andrews Experimental Forest

A sampled stump. The wedge, top left, will be taken back to the OSU Tree Ring Lab for processing and analysis to determine the year of the fire scar, which appears as a dark ring toward the center of the tree.

Fire history sampling crew from OSU: Will Scypinski, Amanda Brackett, Sy Graber

The top of a tree stump is cut and then removed, to expose the tree rings. The stump must be cut low to find solid wood, and scars appear more distinctly towards the base of the tree.

After the top of the tree stump is removed, the surface is brushed clean of sawdust so the crew can inspect the tree rings, in search of fire scars. This stump did not show any fire scars.

This sample reveals a fire scar, with a blackened tree ring bordered by resin and surrounded by curved growth rings of wood in subsequent years

Meg Krawchuk (left) looks on as Andrew Merschel points out a fire scar on a sample taken earlier in the day.

Western sword fern (Polystichum munitum) and Wood Sorrel (Oxalis oregana).

OSU technician Sy Graber samples the stump in a recently burned area of the forest

Meg Krawchuk (left), Matthew Betts (center), and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Meg Krawchuk (left), Matthew Betts (center), and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Meg Krawchuk (left) and Andrew Merschel (right) inspect a sampled tree stump which shows a fire scar from a fire approximately 175 years earlier.

Sampled tree stump with a fire scar and additional indicators of structural damage and branching.

Inspecting a sample of wood, showing a fire scar, taken from a tree stump

Inspecting a sample of wood, showing a fire scar, taken from a tree stump

OSU technicians Will Scypinski (left) and Amanda Brackett (right) use a chain saw to remove the top of an old stump

OSU technicians Will Scypinski (left) and Amanda Brackett (right) use a chain saw to remove the top of an old stump

The lichen reciprocal transplant experiment involves hanging different species of lichen anchored into embroidery hoops, one hoop from each tree has a tempurature reader attached

Field technician Melissa Mauk records the diameter of a live overstory tree in the study plot

Field technician Melissa Mauk records the diameter of a live overstory tree in the study plot

Undergraduate researcher Spencer Jackson and project lead Andy Bluhm look for the metal tag of a tree that burned in the 2023 Lookout Fire

Jack Horton, Ruric Bowman, Andy Bluhm, Spencer Jackson

RS21 in the HJ Andrews Experimental Forest, July 2025

Mature forest along Lookout Creek in the HJ Andrews Experimental Forest

Mature forest along Lookout Creek in the HJ Andrews Experimental Forest

Andy Bluhm next to one of the bigger trees in the HJ Andrews Experimental Forest

Andy Bluhm next to one of the bigger trees in the HJ Andrews Experimental Forest

Andy Bluhm next to one of the bigger trees in the HJ Andrews Experimental Forest

Mature forest along Lookout Creek in the HJ Andrews Experimental Forest

Student researcher Kian Howe records stem distance for mapping using a laser survey tool (total station)

Student researcher Kian Howe records stem distance for mapping using a laser survey tool (total station)

Student researcher Kian Howe records stem distance for mapping using a laser survey tool (total station)

Andy Bluhm next to one of the bigger trees in the HJ Andrews Experimental Forest

Researcher Gabby Robinson records information on each woody plant in the study plot with a diameter larger than 1 cm

Researcher Kate Forsman moves through Reference Stand 38, with a tape to measure tree diameter

New tree tags, attached to trees that will become part of the long-term study

Researcher Gabby Robinson uses a caliper to measure the diameter of a tree in the study plot RS38

Researcher Gabby Robinson records the diameter of a tree in the study plot RS38

Researcher Gabby Robinson flags a tree that will later be mapped as part of the study

Researcher Kate Forsman holds a marked up PVC pipe used with the laser tool to map out tree stems in a plot

Student researcher Kian Howe records stem distance for mapping using a laser survey tool (total station)

Researcher Kate Forsman reads off information about the tree behind her that will become part of the long term study. Species, size, condition.

Researcher Sydney Gastman records diameter of a tree in the study plot RS38

Researcher Sydney Gastman records the tree tag number of a tree in the study plot RS38

Researcher Sydney Gastman uses a wax pencil to mark the height at which she'll measure the diameter of this small tree

Researcher Sydney Gastman measures tree diameter

Researcher Kate Forsman holds a PVC pipe that is marked and used with the laser tool to map out tree stems in a plot

Samples of Douglas fir being measured for water potential.