A large front yard tree in a San Joaquin Valley community like Modesto provides the following benefits each year:

  Saves $30 in summertime air conditioning by shading the building and cooling the air (250 kWh), about 9% of total annual air conditioning cost.

  Absorbs 10 lbs of air pollutants, including 4 lbs of ozone and 3 lbs of particulates.  The value of pollutant uptake by the tree is $45 using the local market price of emission reduction credits.  Uptake of NOx by the tree is equivalent to NOx emitted by a typical car driven 3,600 miles.

  Intercepts 760 gal of rainfall in its crown, thereby reducing runoff of polluted stormwater and flooding.  This benefit is valued at $6 based on local expenditures for water quality management and flood control.

  Cleans 330 lbs of CO2 (90 lbs C) from the atmosphere through direct sequestration in the tree’s wood and reduced power plant emissions due to California Energy Commission’s price of $30/ton. This tree reduces the same amount of atmospheric CO2 as released by a typical car driven 500 miles.

  Adds about 1% to the sales price of the property, or about $25 each year when annualized over a 40-year period. This assumes a median residential property sales price of $100,000.

The value of all benefits is $111 in this example.  Typically, a city will spend $20-$40 per year to maintain a street tree of this size (sometimes located in a front yard easement) and a resident will spend about $10 per year maintaining a large yard tree.  Our benefit-cost analysis for Modesto’s 90,000 street/park trees found $1.89 returned annually for every $1 invested in stewardship.

Information provided by:

Greg McPherson, PhD

USDA Forest Service, PSW

C/o Dept of Environmental Horticulture

University of California

One Shields Ave

Davis, CA 95816

530.752.5897 (fax) 530.752.6634

egmcpherson@ucdavis.edu, web-site: wcufre.ucdavis.edu