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Vegetation

Basin Topics > Vegetation

The vegetation of the Lake Tahoe Basin is an often overlooked, yet remarkable, natural resource that ranges from deep water plants living more than 300 feet below the surface of the lake to uncommon plant communities on the summit of Freel Peak at 10,881 feet. Plants and plant communities that live between these extremes are described as common, uncommon, or sensitive:[Photo]: Lake Tahoe vegetation   Copyright: Jim Morefield

  • Common vegetation in the Lake Tahoe Basin can be categorized by tree-plant type such as, Subalpine Forest, Shrub Association, Deciduous Riparian, and Meadow Association.
  • Uncommon vegetation communities, such as the deep waters of Lake Tahoe or Osgood swamp, are recognized by unique qualities that allow for uncommon plant communities.
  • Sensitive plants, such as Tahoe Yellow Cress, are very susceptible to changes in the environment and require constant conditions to thrive; these are rare plants unique to Tahoe.
The vegetation conditions and patterns of today in the Lake Tahoe Basin are a reflection of past and current human activities. Logging activities began in 1859 and within 40 years about 60 percent of the Tahoe watershed had been clear-cut. The remaining land was characteristically alpine, barren or inaccessible (USDA 2000). After most of the logging was complete, federal and state governments began acquiring lands in 1899 and intensified acquisition in the 1930s.
 
The “second growth” forest that has grown in the past century has, until recently, received little active management, except fire suppression. As such, today’s forest is even-aged and crowded, with many trees suppressed by the density of the surrounding forest. A drought, which started in the late 1980s, stressed the overstocked trees, making them susceptible to insects. In 1991 the United States Forest Service estimated that 300 million board feet of timber were dying or dead (USDA 2000). This condition has increased the threat of large catastrophic fire, and is indicative of a forest where many natural processes have been excluded.
 
[Photo]: View of Lake Tahoe vegetation with mountain background   Copyright: Aric van StaverenHousing, commercial and infrastructure construction have also influenced today’s vegetation patterns. Large and small trees have been removed for these projects and forest structure and composition are manipulated around the urban area, as a defensible space for fire protection. In addition, road salts and soil compaction can stress remaining trees to the point where the tree is later removed as a hazard. The impacts of construction and hazard tree removal are not known; however, the impacts have not been evenly distributed within the Basin. 

New impacts as a result of construction will continue in the montane zone as most of the remaining buildable lots in the Basin are within this zone. Lost urban trees are not replaced quickly, nor are there mechanisms to ensure lost trees are replaced.
 
The current assemblage and health of native plant species and plant communities in the Basin is the result of natural disturbance, changing climate, and human influences and management. Global and regional climate change influence natural disturbance regimes and may affect the integrity and resilience of an ecosystem. Human activities have permanently altered many locations and disrupted some natural disturbance regimes thereby shifting the dynamic mosaic of vegetation types and structures on the landscape. An ecosystem approach focused on encouraging the appropriate diversity of plant species and communities while maintaining ecological function provides a foundation for management and treatment.