Hillsboro Urban Forest

In 2020, Hillsboro had 18% urban tree canopy cover and 28% possible planting area, not including any surface water bodies within the city. The City’s urban tree canopy percentages above are based only on land area since water bodies are not suitable for planting new trees without significant modification. Land cover percentages were calculated within the total area of interest, which includes water bodies. The City’s total land cover contained 18% tree canopy, 31% non-canopy vegetation; 4% soil/dry vegetation; 46% impervious surfaces, and less than 1% water. The 3,040 acres of tree canopy in Hillsboro provide a multitude of economic, environmental, and social benefits, valued at just over $2.8 million annually, as well as $20 million in carbon storage. City-owned land made up 9% of Hillsboro’s total land area, had 38% canopy cover, and contained 18% of the citywide canopy distribution in 2020. Privately owned land made up the other 91% of the city’s land distribution, had 17% canopy cover, and contained 82% of Hillsboro’s tree canopy. View page 11 of this assessment to see how Hillsboro’s canopy cover compares to that of other nearby municipalities.

URBAN TREE CANOPY CHANGE

Results from this assessment found that Hillsboro’s canopy cover decreased from 19% to 18% (-0.4% or -67 acres) from 2012 and 2020. However, City-owned land experienced a 4% increase (or 47 additional acres) in canopy during the eight-year study period. Of Hillsboro’s 38 zoning types, 17 experienced an increase in canopy coverage. Five zoning types had no change, while 16 lost canopy. Residential (R-4.5) zoned areas experienced the largest canopy loss at 12%, or -21 acres, in eight years. Planned Development Industrial (PDI) zoning type experienced the greatest area increase with 28 acres, or +1%, between 2012 and 2020.

RECOMMENDATIONS

The results of this analysis can be used to develop a continued strategy to protect and expand Hillsboro’s urban forest. This study revealed that citywide canopy has decreased by 67 acres within Hillsboro’s current city boundaries. With 4,646 acres of possible planting area, Hillsboro has the opportunity to increase urban tree canopy coverage on both public and private property. 86% of the City’s PPA falls on private property. With partnerships, education, and outreach programs to private landowners, Hillsboro can aim for gains in the citywide canopy numbers. It is important for the City to use this assessment to inform future investments in the urban forest so that all those who live, work, and play in Hillsboro can benefit from the urban forest. The City should proactively work to protect the existing urban forest and replenish the canopy with additional trees. Through management actions, strategic plantings, and protections for existing canopy informed by the UTC, PPA, and change metrics included in this report, Hillsboro has an opportunity to expand its current urban tree canopy to its fullest potential and achieve environmental equity throughout Hillsboro.

Fill out the form to access the Hillsboro Urban Tree Canopy Assessment.