Parent Layer:
Density Metrics
Name: TreeDensitygt1indbh
Display Field:
Type: Raster Layer
Geometry Type: null
Description: - Metric Name: Density – Trees Per Acre
- Tier: 2
- Data Vintage: 2022
- Unit Of Measure: Live trees/acre
Trees per acre (TPA) is a common forest structure measurement that provides a useful index of forest and habitat condition. Many other metrics can be derived from having accurate estimates of trees per acre.
- Creation Method: The F3 model generated several raster surfaces of trees per acre as estimates of tree density on the landscape. This raster surface represents all live trees greater than 1” dbh (TPA). Reference conditions can be generated from contemporary reference sites for mature forest conditions outside of the WUI.
2019 to 2021 Update: Values for 2021 were adjusted using the Ecosystem Disturbance and Recovery Tracker (eDaRT), described in the Introduction. All eDaRT events beginning August 1, 2019 through November 30, 2021 were identified, and the corresponding Mortality Magnitude Index (MMI) values for these events was summed, giving the estimated fractional canopy cover loss per 30m pixel over that time period. The MMI value for canopy cover loss was used as a direct proxy to estimate TPA loss, using the formula:
2021 TPA = 2019 TPA – (2019 TPA * MMI/100)
Although the assumption of direct correlation between canopy cover and TPA should be viewed with caution, it serves as a reasonable approximation for representative mixed conifer forests in the Sierra Nevada affected by the recent drought (Slaton et al. 2022).
Service Item Id: 4b948257d9be47ffb335528ab78ae5fd
Copyright Text: F3 data outputs, Region 5, MARS Team
USDA Forest Service - Region 5 - Pacific Southwest Region
Default Visibility: true
MaxRecordCount: 0
MaxSelectionCount: 0
Supported Query Formats: JSON, geoJSON, PBF
Min Scale: 0.0
Max Scale: 0.0
Supports Advanced Queries: false
Supports Statistics: false
Has Labels: false
Can Modify Layer: false
Can Scale Symbols: false
Use Standardized Queries: true
Supports Datum Transformation: true
Extent:
XMin: 598405.1059297166
YMin: 4425679.902406027
XMax: 616178.9482105562
YMax: 4446630.660537689
Spatial Reference: 26910
(26910)
LatestVCSWkid(0)
Drawing Info:
Advanced Query Capabilities:
Supports Statistics: false
Supports OrderBy: false
Supports Distinct: false
Supports Pagination: false
Supports TrueCurve: true
Supports Returning Query Extent: true
Supports Query With Distance: true
Supports Sql Expression: false
Supports Query With ResultType: false
Supports Returning Geometry Centroid: false
Supports Binning LOD: false
Supports Query With LOD Spatial Reference: false
Supports Percentile Statistics: false
Supports Having Clause: false
Supports Count Distinct: false
Supports Time Relation: true
Supports Sql Format: false
Supports Query Analytic: false
Supports Query With Current User: true
HasZ: false
HasM: false
Has Attachments: false
HTML Popup Type: esriServerHTMLPopupTypeNone
Type ID Field: null
Fields:
None
Supported Operations:
Query
Query Attachments
Query Analytic
Generate Renderer
Return Updates
Iteminfo
Thumbnail
Metadata