Upper Montane Zone
This indicator characterizes the proportion of the Tahoe Region within the upper montane zone (between 7,000 feet and 8,500 feet in elevation) dominated by stands of old growth conifers. Old growth forests tend to be more structurally and biologically complex and resilient to natural disturbances (such as wildfire) than younger forests, due to tree spacing and fire resistance of bark on mature trees, especially pines. Soil conditions, aspect, hill slope position, drought frequency, direct sunlight, fire suppression, climate patterns, time, and natural disturbance influence the extent and distribution of large-diameter trees. TRPA and Environmental Improvement Program (EIP) partners have adopted several policies, ordinances and implementing programs designed to promote the conservation and protection of old growth forests.
Status
Estimated acres of conifer stands dominated by trees greater than 25-inches dbh (“old growth” forest stands) in Upper Montane elevation zones in the Tahoe Region. Stands in urban/developed are not included in calculations towards threshold standard attainment. Some forest types remain unclassified resulting in the N/A column.
Evaluation Map
Late Seral - Ecobject 2010. Stands in urban/developed appear on the map, but are not included in calculations towards threshold standard attainment.
2019 Evaluation
- Status
- Considerably Worse Than Target
- Trend
- Little or No Change
- Confidence
- Low
Applicable Standard
VP14: 60 percent of the Upper Montane zone (between 7,000 and 8,500 feet elevation) must be in a later seral or old growth condition. The Upper Montane zone will contribute 30 percent (45,900 acres) of forested lands towards VP12.
Key Points
- Late seral growth covers 1.8 percent of the upper montane zone, considerably worse than the standard of 60 percent.
- The majority of the Region's trees were logged in the Comstock era, so that today's forest is largely mid-stage second growth. In absence of catastrophic wildfire, it is estimated that the Region's second growth forest will mature into old growth in about 100 years.