About the Application


California has been facing the worst epidemic of tree mortality in modern history. Five years of drought, combined with the increased infestation of native bark beetles, have contributed to the death of millions of trees on federal, state, and private lands across California.

The purpose of this viewer is to allow private citizens and stakeholder entities to participate in understanding the areas of greatest impact. Primary layers include the USFS Aeriel Detection Survey (depicting Tree Mortality), High Hazard Zones (for prioritizing hazard tree removal), and public Mortality Projects (where hazard tree removal projects have occured).

For more information about the various layers, or to get help with the application tools, see the help page by clicking on the help button on the upper right. For more information on bark beetles and wildfire prevention and preparedness, visit www.PrepareForBarkBeetle.org.

Technical Assistance

Technical questions about the use of this viewer can be directed to FRAPdatacontact@fire.ca.gov.


Tree Mortality

These datasets depicts drought related tree mortality, mapped by the USDA Forest Service during aerial detection surveys in California USFS Region 5 from 2012 through 2017. The data includes estimates of trees per acre and numbers of trees affected, tree species affected, damage type, and damage causing agents when available.

Service URLs: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2017/MapServer http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2016/MapServer http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2015/MapServer http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2014/MapServer http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2013/MapServer http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2012/MapServer

Tree Mortality - USFS 2017 Flown Area

Tree mortality and other forest damage is detected by annual aerial surveys over forested lands by the US Forest Service yearly. The surveys are done by flying over the forests and sketch mapping areas of mortality. This dataset represents the flight paths of the 2017 Aerial Detection Survey, and can be used to determine areas that have been surveyed versus areas that have not.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFSTreeMortality_2017_flight/MapServer

Tier One High Hazard Zones

These zones represent areas of tree mortality in direct proximity to assets determined to be important to life and property (including communications, transportation, recreation, communities, and utilities). They represent a direct threat to public safety from falling trees.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DE_HHZTier1/MapServer

Tier Two High Hazard Zones

These are high hazard zones defined by watersheds (HUC 12, average 24,000 acres) that have elevated tree mortality as well as significant community and natural resource assets. Work at the Tier 2 level addresses the immediate threat of falling trees and fire risk, and also supports broader forest health and landscape level fire planning issues.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DE_HHZTier2/MapServer

Mortality Projects

Information about treatment projects that are planned, occuring, or have occured in response to tree mortality. This dataset only includes projects that have been officially submitted and approved for public release, and is updated every other month.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/MortalityProjects_Public/MapServer

Asset - Communications

This service depcits communications structure and facilities in California. It is a compilation of Federal Communications Commission (FCC) data and CAL FIRE communications data. The layer has 3 pieces of information: Unit, Description, and Agency. The unit, where applicable, describes the CAL FIRE unit the facility lies in. The Description describes the facility. And the Agency, when available, describes the Agency responsible for the facility.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DEAsset_Communications/MapServer

Asset - Transportation

This layer depicts important transportation systems. There are four individual components. All Roads are al major and minor roads and is compiled from 2010 US Census Bureau TIGER roads as well as county road data when available. Primary and Seoncdary Roads is a subset of All Roads and is only major local roads, county highways, state highways, US highways, and Interstates. Rail Roads are rail lines througout California. And Rail Stations are rail staions associated with Rail Roads.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DEAsset_Transportation/MapServer

Asset - Utilities

This layer depicts utilities most likely to be affected by tree mortality. There are three utilities depicted: power lines, pipelines, and water supply flumes.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DEAsset_Utilities/MapServer

Asset - Recreation

This layer depicts recreational areas, structures, and facilities in California. It is primarily California State Parks and USFS recreational areas, but does have other agencies' data. There are point locations for areas, structures, and facilities and polygon locations for more spatially explicit areas.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DEAsset_Recreation/MapServer

Asset - Communities

This layer depicts communities by incorporated and unincorporated, community name, and population size. The layer is a combination of 2010 US Census Designated Places (CDP) and CAL FIRE's Incorporated Cities.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DEAsset_Communities/MapServer

Reference - Parcels

This service contains statewide parcels. This includes parcel boundaries, as well as county and APN, but no other associated attribute information. It represents a combined package of parcels from individual counties obtained from Digital Map Products. Because the parcels are maintained at a county level, there are often instances of overlaps or gaps between parcels of adjacent counties.

This service is scale dependent and only visible when zoomed to at least 1:75,000. It can be queried using the identify tool when zoomed to at least 1:20,000. It contains both a dark and a light version to allow viewing against both light basemaps (like streets and topo) and dark basemaps (like satallite).

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/Parcels/MapServer

Reference - Counties

This data layer depicts the County Boundaries of the State of California.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/Counties/MapServer

Reference - WBD HUC12 Watersheds

The HUC12 sub-watershed hydrologic unit boundaries average around 250,000 acres. They are the smallest watershed unit in the National Hydrographic Dataset (NHD) for the state of California. They are subsets of the larger HUC8 watersheds as well as the larger HUC4 regional hydrologic units. They provide a uniquely identified and uniform method of subdividing large drainage areas.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/WBDHUC12watersheds/MapServer

Supporting Layer - Temporary Wood Storage and Processing Sites

This layer shows public processing and storage sites for High Hazard Zone wood and slash from bark beetle and drought killed trees within the 10 High Priority Counties.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/TempStorageSites/MapServer

Supporting Layer - Biomass Facilities

This layer shows biomass power plants which are operating, under development, currently operating but have a pricing agreement or contract nearing expiration, or available to operate (re-start) within 60 days pending a new contract. This data will be updated by the TMTF Bioenergy Working Group and used to develop alternatives to help manage high volumes of biomass.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/ForestPractice/BiomassPowerPlants/MapServer

Supporting Layer - Fire Perimeters

Fire Perimeters from 2010 and up. Only fires 5000 acres or greater are labeled, with labels displaying when zoomed to at least 1:750,000.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/FirePerimeters_recent/MapServer

Supporting Layer - Fire Threat (2005)

The Fire Threat feature class represents a measure of fire hazard that combines an estimate of the area’s likelihood to burn in a wildfire with an estimate of that fire’s physical nature, otherwise known as fire behavior. Fire frequency is based on recent past fire history overlaid on a spatial stratification of bioregional fuel types to define areas of relatively similar burning conditions. This fire frequency model uses the metric of fire rotation, which is equivalent to the number of years required to result in a burned area equal to the size of the strata. Fire behavior is calculated from maps of fuels, terrain and fire weather consistent with wildfire burning conditions, and used Flame Length as the basis for classification. Both fire frequency and fire behavior were classified into Moderate, High and Very High classes, and the resultant Fire Threat class were based on the combination of both factors. The resultant Fire Threat classification results in an addition class of Extreme for cases where both frequency and fire behavior are Very High.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/FireThreat05_1/MapServer

Supporting Layer - Risk of Basal Area Loss due to Bark Beetles and Fir Engraver Beetles

Risk is defined as ‘the expectation that, without remediation, at least 25% of standing live basal area greater than 1 inch diameter will die over a 15 year time frame (2013-2027) due to insects and diseases.’ The total risk layer represents risk derived from all pest agents, including but not limited to: western pine beetle, mountain pine beetle, Douglas-fir tussock moth, sudden oak death, Port-Orford-cedar root disease, etc. The bark beetle risk layer only includes risk from western pine beetle, mountain pine beetle, Jeffrey pine beetle, and fir engraver beetle. The risk map is a national 240m product. This 30m product was generated using the same methods, models, and application at 30m. For more information on the methods, pests included, and base layers, please visit: https://www.fs.fed.us/foresthealth/technology/nidrm.shtml

Service URL: https://foresthealth.fs.usda.gov/arcgisfh/rest/services/NIDRM_Map/BarkBeetle_Total_PctBALoss_CA/MapServer

Supporting Layer - Vulnerability from Water Stress

The vulnerability data indicates potential mortality. It is derived from the Progressive Water Stress (PWS) that strives to detect significant water loss at some point in the last 4 years. While this does not necessarily mean there is mortality in the area, it probably does mean that it is more likely. The thresholds are a starting point to indicate the level of risk, but these can very likely be improved over time and feedback is welcome. By Carnegie Airborne Observatory, Carnegie Institution for Science. For more information see https://cao.carnegiescience.edu/The source document that details the methods used in generating the maps can be found at http://www.pnas.org/content/113/2/E249.abstract

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/CAO_VulnerabilityFromWaterStress/MapServer

Supporting Layer - Progressive Water Stress

Unclassed Progressive Water Stress (PWS), which strives to detect significant water loss at some point in the last 4 years. While this does not necessarily mean there is mortality in the area, it probably does mean that it is more likely. By Carnegie Airborne Observatory, Carnegie Institution for Science. For more information see https://cao.carnegiescience.edu/The source document that details the methods used in generating the maps can be found at http://www.pnas.org/content/113/2/E249.abstract

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/CAO_ProgressiveWaterStress/MapServer

Supporting Layer - USFS Designated Insect and Disease Areas

This feature class contains data that depicts National Forest System (NFS) Lands within California designated under section 602 of the Healthy Forest Restoration Act. These are areas that will be prioritized by the USFS for treatment. Designated areas are based on a set of eligibility criteria regarding forest health where areas are experiencing, or at risk of, an insect or disease epidemic. These areas do not include any areas coinciding with Wilderness and Wilderness Study Areas. The data is comprised of selected HUC-12 units clipped to Proclaimed National Forest boundaries. Non-Forest Service land ownership areas (inholdings) are also removed.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/USFS_HFRADesignatedWatersheds/MapServer

Supporting Layer - Electric Utility Service Areas

This layer depicts Electric Utility Service Areas in California, and was made available by the California Energy Commission.

Economists have long recognized the distribution of electricity is a “natural monopoly” for a defined geographic area. Within each area a single company (public or private) is responsible for maintaining the infrastructure of local utility-owned substations and the network of distribution wires that operate at voltages less than 69 kV.

The utility distribution company (UDC) may be an investor-owned utility (such as PG&E) or a publicly owned utility (such as SMUD) or a rural electric cooperative (such as Plumas-Sierra). The end-use customers in a utility service area are all connected to the wires of the same UDC.

Each publicly owned utility and investor-owned utility (IOU) in California has an obligation to serve all the electricity customers in its service area. However, customers in the service areas of California’s three large IOUs may purchase their electricity supply from non-wires entities known as Community Choice Aggregators (such as Marin Clean Energy) or Energy Service Providers (such as Constellation NewEnergy). These non-wires load serving entities purchase wholesale quantities of electricity from the market and schedule those deliveries across shared transmission lines and the UDC networks of the IOUs.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/ElectricUtilityServiceAreas/MapServer

Supporting Layer - Land Ownership

This dataset is intended to provide a statewide depiction of land ownership in California. It is comprised of ownership information derived from federal agencies and adjested to match SRA/parcels where appropriate, with non-federal data primarily derived from the California Protected Areas Database (CPAD). Areas without an ownership feature are ASSUMED to be private.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/ownership/MapServer

Supporting Layer - Vegetation

The State of California was mapped using the California Wildlife Habitat Relationships (CWHR) system. An accurate depiction of the spatial distribution of habitat types within California is required for a variety of legislatively-mandated government functions. The California Department of Forestry and Fire Protection's CALFIRE Fire and Resource Assessment Program (FRAP), in cooperation with California Department of Fish and Wildlife VegCamp program and extensive use of USDA Forest Service Region 5 Remote Sensing Laboratory (RSL) data, has compiled the "best available" land cover data available for California into a single comprehensive statewide data set. The data span a period from approximately 1990+. Typically the most current, detailed and consistent data were collected for various regions of the state. Decision rules were developed that controlled which layers were given priority in areas of overlap. Cross-walks were used to compile the various sources into the common classification scheme, the California Wildlife Habitat Relationships (CWHR) system.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/fveg_WHR13/MapServer

Supporting Layer - Direct Protection Areas

The DPA layer delineates the dividing lines between land that will be provided wildland fire protection by the State, Federal, and Local agencies. The Cooperative Fire Management Agreement (CFMA) between the federal agencies and the California Department of Forestry and Fire Protection (CAL FIRE) is the primary mechanism that provides the framework for wildland fire protection responsibilities statewide. Through this mechanism the state has been divided into practical Direct Protection Areas (DPAs) corresponding with each agency's responsibility. The participating agencies submit proposal for changes to their DPA where necessary. If changes are agreed upon by all parties involved, then the change is approved and the layer is updated.

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/DPA/MapServer

Supporting Layer - Responsibility Areas

The SRA dataset shows where the legal fire protection responsibility is:

Service URL: http://egis.fire.ca.gov/arcgis/rest/services/FRAP/SRA/MapServer


The basemaps used in this application are freely available services by ESRI. More information about these layers can be found here:


The Toolbar

Most of the tools you need for this application can be found on the vertical toolbar on the left side of the screen. Tools include:

(Plus/Minus) Zoom In/Out

(California) Original Extent

(List) Legend

(Checkbox) Layer Visibility

(Binoculars) Address Search

("i") Identify Tool

(Double Arrow) Layer Swipe

(Printer) Map Export

Further information about the tools follow.


Users can use the mouse, keyboard, and/or map tools for navigating the map. Specifics are as follows:


Mouse controls:

Keybord controls:

Mouse plus Keyboard:

Map Tools:


Mouse controls:

Keybord controls:

Mouse plus Keyboard:


The map can be returned to the original extent (California full extent) by clicking on the Home button (California icon) on the vertical toolbar on the left-hand side of the window.

Overview Map

The overview map can be opened (or closed) by clicking on the white arrow in the bottom-left corner of the window.

The overview map will show whatever basemap you currently have displayed, with a semi-transparent box depecting your current extent. You can drag the box to pan the map.

Specific Locations

To navigate to a particular address, see the Address Search tool, below.


This application displays multiple layers. Information about these layers can be found in the Datasets section, above. To get symbology information about visible layers, use the Legend tool. To change the transparency of a layer, or to toggle a layer on or off, use the Visibility tool. To change the basemap, use the Basemap section of the Visibility tool. Further information about these tools follows.


The Legend panel can be opened by clicking on the Legend button (list icon) on the vertical toolbar on the left-hand side of the window.

The Legend panel displays on the right hand side of the screen when active. It can be closed using the "X" on the upper-right of the panel or by clicking the Legend button a second time. Activating "conflicting" tools will also automatically close the Legend panel.

The Legend displays symbology information for all layers available for the map.


The Visibility panel can be opened by clicking on the Visibility button (eye icon) on the vertical toolbar on the left-hand side of the window.

The visibility pane displays each service used in the application, and any "sub-layers" in the case of services that contain more than one layer. Use the checkboxes to toggle services (or "sub-layers") on and off. Use the slider to adjust the transparency of the service. "Sub-layers" can not have their transparency adjusted individually - only the service as a whole.


At the bottom of the Visibility pane (see above), you will find the basemap controls. Use the select box to swich basemaps, and the slider to adjust the transparency of the basemap. For most basemaps, moving the transparency all the way down will give a plain white background.

Address Search

The Address Search panel can be opened by clicking on the Search button (binoculars icon) on the vertical toolbar on the left-hand side of the window.

The Zoom To Address tool uses geolocation to navigate to a particular address. Enter the address you would like to navigate to, and click the zoom button (magnifying glass icon).

The Zoom To Address tool will zoom in to the location the geocoder matches to your entered address, and place a red marker at that location.

The marker will remain until removed by clicking the Clear Marker button (eraser icon) on the lower right of the Zoom To Address tool.

Identify Tool

The Identify tool can be activated by clicking on the Identify button ('i' icon) on the vertical toolbar on the left-hand side of the window. This tool does not open a panel. Instead, clicking the button activates or deactivates the tool. The button is black when active.

Once activated, to use the tool, simply zoom in to your area of interest and click on the map. The application will query the relevant services and open a dialog with the results (and highlight the relevant feature or grid).

Note that the speed of the query may vary - while pinging the services your cursor should switch to the progress symbol to indicate that the tool is working.

For this particular application, the Identify tool can query the following layers: Tree Mortality, Assets, Parcels, Biomass Plants, Vegetation, Designated Watersheds, PGE Circuit Areas, and Electric Utility Service Areas. A layer will only return results if that layer is currently on/visible.

Swipe Tool

The Layer Swipe tool can be activated by clicking on the Layer Swipe button (double arrow icon) on the vertical toolbar on the left-hand side of the window.

This tool does not open a panel. Instead, clicking the button activates or deactivates the tool. The button is black when active.

When active, the swipe tool adds a verticle bar to the map. This bar can be slid right or lift by clicking and dragging the handle. The tool controls the visibility of the swipable layers (as a set): to the left of the bar those layers will be visible, whereas to the right they will not, revealing the basemap underneath.

For this particular application, the following layers are swipable: Tree Mortality, CAO Data.

Map Export Tool

The Map Export tool can be opened by clicking on the Map Export button (printer icon) on the vertical toolbar on the left-hand side of the window.

This tool opens a modular dialog box. Use this Map Export Tool to create a letter-sized map, with custom title, orientation, and format. The map will include the currently viewed extent and layers. The exported map will not include a legend, although this functionality should become available in a future update.

The speed with which the map is created depends on a number of factors, including which layers are included, the extent of those layers, and the current load on the servers. The dialog will update while the map is being created, and will provide a link to the generated map upon completion.

HELP - Tree Mortality Viewer