SACRAMENTO -- Bernard Flynn pushes branches aside as he walks down a dirt path toward the American River, stopping to point out the variety of shrubs and trees that have blossomed along its banks.

For most hikers, the prickly leaves and twigs are cumbersome obstacles that pierce blue jeans and scratch the arms, but Flynn believes there should be more trees and bushes along the state's rivers.

The tree line along the American River across from Sacramento State University is what Flynn describes as an example of a healthy riverbank that provides habitat for birds, insects and amphibians.

It's the type of landscape he has been planting for more than a decade along some of the Central Valley's main river systems.

A former almond and prune farmer who adapted agricultural planting techniques to river restoration, Flynn, 71, is one of 15 finalists for a national award recognizing the work of Americans over age 60.

More than 1,200 individuals were nominated for the inaugural Purpose Prize, which was developed by Civic Ventures, a San Francisco-based nonprofit. Five winners will be selected in September and will get $100,000 each, with runners-up receiving $10,000.

Flynn began the restoration of riverbanks by chance in the early 1990s after he sold 500 acres of flood-prone farmland south of Redding to the U.S. Fish and Wildlife Service, which bought the property for habitat conservation.

The agency had little experience in planting trees, so it paid Flynn to do the job. It needed trees planted to create habitat for migrating birds while at the same time stabilizing the riverbank against erosion.

Flynn created a computerized database that organized large-scale restoration planting. In doing so, he followed agricultural and irrigation models he had developed as manager of Shasta View Farms, along the Sacramento River about 10 miles south of Red Bluff in the northern section of California's Central Valley.

By color-coding trees on the computer and labeling the saplings according to soil conditions, tree types and water well locations, Flynn created diverse landscapes on the screen. They were translated to the land he had sold to the government, and within three years yielded riparian forests.

"The use of farm technology allowed us to do large-scale plantings that they weren't used to," Flynn said of the Fish and Wildlife Service scientists. "And plantings that were predictable."