Tree Canopy

Tree canopy refers to a tree's leaves, branches, and stems that cover the ground when viewed from above.

Because of the many superpowers trees provide, like shading a hot August pavement, monitoring canopy cover is important. And we can measure it. We do so using a mapping technology which extracts tree canopy data from photo images taken by satellites and airplanes during the growing season when trees have leafed out.

Once images were captured, the recipe for making this data was automated. AI detected and labeled image pixels as tree canopy. Similar pixels were grouped and turned into shapes outlining tree canopy. To ensure correctness, mapping professionals reviewed the data making manual edits when needed. And voilà, tree canopy data was made.

An independent review by the City of Austin and the Texas A&M Forest Service revealed an overall accuracy of 98%. 1,000 locations were assessed for whether the canopy data matched the underlying imagery. Only 23 errors were found.

Caution: Since the 1970s, Austin's canopy has been documented from various sources. Beginning in 2006, the City of Austin standardized the process for creating canopy data. The methods have mostly remained the same since then, however some factors make it difficult to compare canopy cover over time. See the limitations section at the end for more detail.

To view and download this map at the full data extent,  go here .

Land use describes the purpose or function of a piece of land in terms of how people use it. Where we live is residential whereas where we hike is open space. Across many American cities, private residential uses hold the largest single share of land and canopy. This is the case in Austin too. Within the residential category, single family residential (think freestanding house) occupies the most space within Austin's city limits.

Residential: single family houses, duplexes, mobile homes, and multi-family (apartments).

Undeveloped: either agricultural land or non-parkland without a building structure.

Open Space: parkland, preserves, conservation lands, greenbelts, recreation areas.

Right-of-Way: streets, roads, sidewalks, and other transportation-related places.

Commercial: retail shops, offices, mixed uses; includes industrial uses like warehouses.

Other: civic uses like churches, hospitals, schools; utilities, water, and unclassified land.

Right-of-Way (ROW) is publicly-owned land, including streets, sidewalks, and the area behind the curb. Everything from the street to the property lines. ROW boundaries may vary at different locations.

Still unclear? Click  here  for more on our public right-of-way.

Residential (36%) and open space (30%) land uses contain the most tree canopy in Austin. There's nearly equal the amount between the two.

A look at land and canopy across various land uses as of May 2023. Residential, open space, and undeveloped land uses account for 86% of all Austin's tree canopy citywide.

Achieve at least 50% citywide tree canopy cover by 2050, focusing on increasing canopy cover equitably

Our  Climate Equity Plan  lays out a goal for tree canopy to cover half the city by the year 2050. Is this goal feasible? Right now, canopy covers 41% of our city. It's estimated we have 143K acres of additional plantable space. If we planted and grew canopy in this space plus maintained our existing canopy cover it's possible to achieve and even exceed our canopy goal.

The greatest planting opportunities reside on private land mainly because private land makes up the largest share of land ownership in Austin, but also because that's where the majority of plantable space is located. When we look at public land owned by the City of Austin, street rights-of-ways comprise nearly half of all public land and offers the largest amount of plantable space compared to other public land uses like parks and libraries. This is partly due to the sheer amount of land occupied by the right-of-way (39K acres) and partly due to public parkland being already largely planted out.

Below is a full list of canopy and land statistics broken out by jurisdiction type for the City of Austin. The main takeways are

1. Most tree canopy and available planting space is located on private land.
2. There's nearly equal the amount of land and canopy in Austin's ETJ as there is in its full purpose jurisdiction.
3. As expected, there's more plantable space in Austin's ETJ compared to its full purpose jurisdiction. This has implications for future urban development and growth into our ETJ.

1. Full Purpose: City of Austin provides full municipal services, assesses taxes, and enforces City ordinances/regulations.
2. Limited Purpose: land development and environmental ordinances/regulations are extended. No City taxes collected and no municipal services provided.
3. Extraterritorial Jurisdiction (ETJ): unincorporated areas within 5 miles of the city’s boundary and not within the city limits or the ETJ of another city. No City taxes collected and no municipal services provided.

A note on annexation: in addition to actual gains or losses in canopy, the change in tree canopy from one time period to another is impacted by the amount of land within Austin's jurisdiction. That amount changes from one year to the next due to annexation and dis-annexation. For example, in 2019 the City of Austin dis-annexed the Austin Community Landfill—a property over 800 acres. On the other hand, many land parcels have been annexed since 2018. Because canopy cover is calculated as canopy acres divided by land acres, the denominator is impacted by any annexed or dis-annexed land over the time period. However, many annexations have been conversion from ETJ or LTD purpose to full purpose rather than new land annexations, which doesn't impact the overall amount of land in our jurisdiction. Further, the amount of land annexed between two canopy monitoring time periods is usually not enough to impact the citywide canopy cover percent value. Still, annexations must be monitored otherwise incorrect conclusions may be made about our canopy.

To view a list of recent annexations, please visit the  City of Austin's approved annexation webpage. 

Forest connectivity describes tree canopy's form and the leafy bridges that link different trees together. An urban forest is made up of both connected and fragmented trees. We can describe forest connectivity in terms of patterns and linkages.

The European Union provides a method to classify canopy by geometry and connectivity into seven classes. The following map shows canopy data symbolized by these classes in downtown Austin. Core identifies the heart of canopy whereas Perforated shows where their are holes in canopy. Bridges form links between. Islets are like islands of disjointed canopy. This information can be used to better understand where gaps in canopy exist for things like planting trees to provide shade along a trail or connecting wildlife habitats.

Current and historic tree canopy datasets may be downloaded at the City of Austin's open data portal using the following links. Effort to collect tree canopy data began in base year 2006 and has occurred on a 4-year cycle.

The following data are also available in  ArcGIS Online. 

A note on the limitations of these data. All geospatial data are uncertain to some degree. Data are never perfect and will never be. This includes our tree canopy data. It simply represents a snapshot in time and it was not collected for intended purposes of detecting canopy change over time. Therefore it's not recommended this data be used to compare gains or losses in tree canopy from one time period to another. Sources of uncertainty—making time period comparisons difficult—include aerial image resolution and source, methods used, an aerial image's camera tilt, and things like shadows or objects obstructing our ability to view canopy in the imagery. Canopy data in this analysis are provided simply as estimates for making general comparisons over time.

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