Yellowstone (YELL)

Yellowstone (YELL)

Lane Scher, Jordan Luongo, Jim Clark

13-17 September 2018
Monthly effective precipitation over the last five years (left) and annual values since 1960 (right). At left are shown winter surpluses in blue and summer deficits in orange. At right are annual anomalies in minimum winter temperature and annual deficit.
Annie Carlson assisted with permitting and background advice.

Parent materials combine a history of volcanism, faulting, and glaciation.  The park remains seismically active, with frequent earthquakes and many hydrothermal features.    Vegetation includes a mosaic of forest, sagebrush-steppe and riparian bottomlands.  At high elevations sub-alpine Pinus albicaulis, Pinus flexilis, Picea engelmannii, and Abies lasiocarpa transition to alpine habitats.  Forests are dominated by Pinus contorta and Pseudotsuga menzeisii throughout much of the part.  Stand-replacing fires create a patchwork of nearly even-aged P. contorta stands.  Our sampling was focused on NEON plots at low elevations in the northern portion of the park, those supporting forests.

Grizzly bears are omnivores, this one digging for roots and/or invertebrates

Annie Carlson, Research Coordinator for Yellowstone NP facilitated our sampling efforts, including on-site consultations. Amy Jacobs manages NEON operations for this domain and provided guidance on logistics and sampling.  Housing was obtained in Gardner, MT with convenient access to sites in the northern portion of YNP.

Plot 7 is a bison hangout.

Plot 7 is an oasis of Pseudotsuga menzeisii on a mountainside, surrounded by sagebrush steppe, with grasses in the understory. Bison frequent the site, possibly maintaining the grass understory. Residual charred boles indicate that the surrounding steppe replaced forest decades ago.  There are some Pinus contorta and browsed Populus seedlings in surrounding steppe. Most of the 2018 cone crop (on trees) have started to open by sampling time.

Some lodgepole cones had opened, but still held seed.

Plot 20 is a 30-yr old even age Pinus contorta stand with trees dating from the 1988 burn. Cones are mostly closed at the time of our initial census in 2018, some just starting to open. The understory is grass, with no tree recruitment.  The landscape in this area is a mosaic of forest and grassland.  This site is not yet included in maps below.

Plot 23 occupies an east-facing slope.  The open Pseudotsuga menzeisii canopy includes snapped large trees and clumped recruitment.  Pinus contorta is present but not abundant. The site burned 30 yrs ago in the 1988 fire. In additional to patchy recruitment, the understory includes sagebrush and grasses.

Plot 26 supports a sparse Pseudotsuga menzeisii canopy above patchy recruitment scattered Pinus contorta. There is substantial damage to tree crowns, especially the large Pseudotsuga menzeisii. The grass understory is littered with large tree boles.  Patchy forest is interspersed with open grasslands.

Camera traps were deployed in July – August 2019.  Further details are forthcoming.