Soaproot Saddle NEON / SOAP

SOAP has a typical Mediterranean, mid-montane climate. Located on the rain-snow transition line of the Sierras, the site is strongly seasonal with cool wet winters and warm dry summers. While higher elevations are snow dominated, SOAP receives winter snow that melts rapidly between weather events and a mean annual precipitation of 900.35 mm (35.4 in.). Mean annual temperature is 13.4°C (56°F), and winters are relatively mild with 212 frost free days per year. Drought and a warming climate have led to pine die-off caused by an outbreak of pine bark beetles, leaving the site at high fire risk due to large areas of dry, dead wood. [3] [4] [7] [9]

The geology of SOAP is granodiorite and quartz monzonite. [6]

Major soil series that are mapped at the SOAP site are Holland (Fine-loamy, mixed, semi-active, mesic Ultic Haploxeralfs), Chaix (Coarse-loamy, mixed, superactive, mesic Typic Dystroxerepts), Chawanakee (Loamy, mixed, active, mesic, shallow Typic Dystroxerepts), and Tollhouse (Loamy, mixed, superactive, mesic, shallow Entic Haploxerolls). [2] [8]

Ponderosa pine (Pinus ponderosa) and incense cedar (Calocedrus decurrens) dominate the overstory, with co-dominant canyon live oak (Quercus chrysolepis) and California black oak (Quercus kelloggii). However, the interaction of long-term drought and warming has exacerbated the outbreak of pine bark beetles, leading to high Ponderosa pine mortality and a potential shift in the forest community. Mariposa manzanita (Arctostaphylos viscida ssp. Mariposa) are interspersed throughout the understory and often form dense thickets in open areas, whereas deerbrush (Ceanothus integerrimus) and poison oak (Toxicodendron diversilobum) are common in the shaded understory. Mountain misery (Chamaebatia foliolosa) provides dense groundcover throughout much of the site. [3]

Soaproot Saddle is part of the U.S. Forest Service’s Major Land Resource Area (MRLA) 22A – Sierra Nevada mountains. The area is used for logging, grazing, and recreation - this includes quail, mule deer, and black bear hunting. Soaproot is managed by the High Sierra Ranger Station and Blue Canyon work station, which conduct controlled burns, logging, and herbicide application to manage the forest for timber and livestock production, as well as fire suppression.

The Critical Zone Observatory maintains an eddy-covariance flux tower and hydrological monitoring instruments to analyze the carbon and water balance and other atmospheric properties of the forest. [1] [5]

NEON plot establishment at SOAP began in 2015 and was largely complete by the fall of 2016. The site transitioned to full operations in August 2018, and terrestrial sampling and observations began. The site’s 52 m (171 ft.) flux tower came online and began streaming data in September 2017.