To control weeds, park employees use extensive mulching and string trimmers rather than pesticides, according to Robert Ward, parks division manager.
Ward said the city is targeting small urban parks such as Sarah Wallis and Scott Park on Channing Avenue for its program to reduce harmful pesticides, herbicides and fungicides, with the hope of applying lessons learned to other parks and open spaces.
The city applied 252 pounds of pesticides to control fungus, rodents, weeds and insects last year, according to a February report that examined alternatives such as using goats, mulches and beneficial insects. (Only active ingredients were measured, many of which are diluted.)
In 2005, the city used 449 pounds of chemicals.
Sarah Wallis Park was chosen because it is close to neighborhoods, said Greg Betts, the city's director of community services. The park is popular for afternoon reading and sunning and is close to neighborhoods, he said.
"We're trying to reduce or eliminate pesticides where people are very close to the landscape," Betts said.
The city is using other pest-control techniques elsewhere. Palo Alto Municipal Golf Course implemented a gopher-trapping program that has proven better at controlling gopher populations than chemical controls and is less expensive, according to staff.
The city also piloted using "bee tunnels" to reroute bees flying to their hives in parks and other public spaces. Bee tunnels reduce the need to kill the beneficial insects, city staff said.
The parks department is hoping to make one or two parks per year pesticide-free. Scott Park and perhaps also Monroe Park could be added this year, Ward said.
City green belts such as around El Palo Alto and Hopkins Creekside Park are also pesticide free, he said.
"No pesticides are used at all at Palo Alto Unified School District athletic fields for 13 elementary and three middle schools," he added.
The city's pest-management program, which it launched formally in 2001 due to state storm-water regulations, combines non-poisonous techniques such as using pest barriers, native plants and biological pest controls with other "organic" methods.
In 2009, the city reduced by 43 percent the so-called "ecotoxic" pesticides, which are harmful to wildlife, staff noted. Many of the chemicals can also affect human health, city staff said.
The city was the first public agency or business to require its pest-control operators to be EcoWise certified in 2007, which required rigorous training in less-toxic techniques and was developed by pest-control and water-quality professionals and the National Resources Defense Council, according to the report.
Developing less-toxic techniques could gain increasing relevance in the coming years.
A May 17 federal court injunction prohibited the use of 75 pesticides where 11 endangered or threatened animal species live in eight Bay Area counties, including Santa Clara County.
The chemicals cannot be used in or near the wildlife habitat areas at least until a 5-year study by the U.S. Environmental Protection Agency (EPA) is completed.
In Palo Alto, some pesticide-free techniques have been applied to larger parks and open space areas, but Ward conceded it might not be possible to completely eliminate chemical use in larger spaces because of manual-labor costs.
Betts said Palo Alto has tried every alternative from steaming weeds to spraying clove oil. Volunteers do manual weeding and string trimming in Arastradero Preserve and Foothills Park, Betts said.
Areas such as sports fields create more challenges, Ward said. Turf grasses are difficult to maintain without fungicides and pesticides.
The city is looking to choose less vulnerable turf grasses, however. Bent grass at Palo Alto Lawn Bowls on Embarcadero Road was susceptible to fungus; the city sprayed the grass every three weeks with fungicide, he said. By switching to Bermuda grass the city was able to reduce its spray regimen to once or twice per year, he said.
Increased labor costs present the biggest challenge to widely using non-toxic methods, Ward said.
A change in public attitude is also helping the program, though, he said.
"The expectation is changing. People are OK with weeds in areas where it was not OK before," he said.
A copy of the staff report on the less-toxic pest-control program can be viewed at www.cityofpaloalto.org/civica/filebank/blobdload.asp?BlobID=19751.
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