At Yosemite, we establish a field camp for two weeks each year and collect data with a team of 30 – 40 students, researchers, and professional field staff.
Camping at Yellow Pine Volunteer Campground in 2009. Molly Barth and Alana Lautensleger work on dinner while the USGS crew discusses ecological theory.
Many of the field participants at YFDP do so as part of UW's Ecology of the Sierra Nevada and White Mountains class. Here the entire 2011 class gathers opposite Bridalveil Falls on a day off (it rained 9.5 cm the night before).
Back at the Hodgdon Meadow Campground, a student assambled a sap-catcher/shade tarp above her tent. Unfortunatly, this tarp did little to protect against the 9.5 cm (!) that came several days later.
Upon arrival at Yosemite National Park, YFDP principal investigator, Jim Lutz, gets right to work in accounting for all the field supplies
A shot of the 2011 field crew campsite at Hogdon Meadows. This was home to the researchers, students, and the USGS crew while working on the plot.
University of Washington students prepare to learn the basics of triangulation from Dr. Jim Lutz. Lembert Dome sits near Tuolumne meadows an has an elevation slightly over 9,400 ft.
Kaitlyn Shwindt, Sienna Hiebert, and Sam Barr (left to right) fill the three water jugs that provide water to the crews while at camp. When full these jugs can weigh over 50lbs- Whew!
After a long day on the plot, the crew can't get enough chips and salsa. Good thing Jim Lutz (meal planner) came prepared.
The crew hastily prepares breakfast and lunch before a long day on the plot. A nice meal, hot coffee, and anticipation of the days work is enough to get this crew up and out by 7am.
A view from the fire lookout at Crane Flat Helitac shows the Yosemite hotshot crew hard at work. The crew worked hard to put out a wildfire which can be see in the distance. This helitac is located near the most assessable plot entrance.
Each day before heading out to resume the mortality survey, teams of 3 to 4 regroup and account for the necessary equipment.
Principal Investigator, Jim Lutz, poses for a picture while identifying the cells four corners. This is the first step upon entering each cell.
Volunteer Alina Cansler fixes a transect line during the survey. Although the plot has a variety of geographic features, this picture shows the slope characteristic of most of the grids in the plot.
Tree 0139 of row 03 has been found! When a tree is found the crew member calls out the trees tag number, species, and whether it is dead or alive. (Photo Taken by: Seth Cowdery)
Kimberly Grant uses the quadrat map to direct fellow crew members. During the mortality survey, no grid cell is complete until all the mapped trees are accounted for.
An old growth Pinus Lambertiana that has acquired a lightening scar since the establishment of the plot in 2009. This tree was still alive during the 2011 mortality survey, but was showed signs of diminishing health and is likely to be dead within the next year. This was one of two neighboring Sugar Pines with impressive lightening scars. Principal investigator, Andrew Larson and wife Alina Cansler pose with the tree.
A massive Pinus lambertiana snag stands among a group of Abies concolor and Calecedrus decurrens. All these species are abundant in the 25.6 ha plot and are commonly associated with white-fir mixed-conifer forests throughout the Sierra Nevada.
Undergraduate crew members, Kimberly Grant (UW) and Katie Meline (WSU), work together to determine the charateristics, condition codes (CCs), and factors assosiated with death (FADs) for this dead tree.
Conks are commonly seen on both dead and alive trees. The YFDP mortality survey records conks as condition code number 19. This picture shows a very large conk, but they aren't always as large (see next picture).
The cankers on this Pinus lambertiana are undoubtedly a result of White Pine Blister Rust. Visibility of these cankers are evidence that the tree was infected at least several years ago. Although it is a common killer of white pines in North America, it was found in lower than expected abundance in the plot.
Condition code 24: Pitch!
The horizontal galleries on this Abies concolor provide the field crew with sufficient evidence that the culprit killer was Scolytus ventralis. YFDP protocol calls for a thorough assessment of all the conditions and factors related to each mortality. Scolytus ventralis is the most common fir killer on the plot, and is frequently coupled with the fungal pathogen, Armillaria.
This photo shows the fungal pathogen Armillaria. Armillaria is commonly found under the bark near the bole or in the soil around an infected tree.
Bole damage is considered a factor that usually leads to a mortality.
Washington State University undergraduate student, Nicole Studevant carefully records measurements during a mortality assessment. The Yosemite Forest Dynamics plot crew pride themselves on the meticulous recording of data.
University of Washington student, Rachel Mickey, measures the height of a possible in-growth. Although the mortality survey was the main focus of the 2011 field crew, All trees that are 1 cm or more at breast height are mapped into the plot.
Nick Mills, a crew member from Eastern Connecticut State University, uses the impulse laser to determine a horizontal distance measurement. This measurement is taken to determine the coordinates of trees that grow into the plot.
Anton Gabrielson, University of Montana senior and pine cone aficionado, shows off his finding during the last day of the 2011 survey
Jim Lutz collates data sheets while fellow PI, Andrew Larsen, and WSU student, Ayana Cleveland, stand by.
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