Georgia's 22 million acres of privately owned forests provide an economic and environmental value of more than $37 billion a year, according to a new study released Wednesday by the Georgia Forestry Foundation (GFF).

The three-year study (PDF) was conducted at the University of Georgia's Warnell School of Forestry and Natural Resources. More than 3,000 Georgia residents were surveyed.

This economic value comes from what the study calls "ecosystem services," including "erosion control and sediment retention for cleaner streams, carbon absorption, storage and retention of water, climate regulation, nutrient cycling, crop pollination, flood control, improving and maintaining air quality, biodiversity, opportunities for non-commercial uses and simple aesthetic contributions," according to the release from GFF.

"There has been quite a lot of talk about ecosystem services in recent years, but until now there has been very little real research to put a dollar figure on this," says Mother Nature Network co-founder and Georgia tree farmer Chuck Leavell. "The answer we have now is quite astounding."

These services are a free benefit to the surrounding communities, said GFF Chairman Wade Hall. "Landowners are not paid for the benefits provided by their woodlands," said Hall, who is also president of Stuckey Timberlands. "But we need to give serious thought to what would happen if we lost them."

These environmental benefits are in addition to the direct economic value of the forests, which generate $29 billion a year through the production timber and other wood products, as well as employment and taxes, according to a report from the Atlanta Journal-Constitution. About 118,000 people are employed by Georgia's timber industry, Tom Lambert of the Georgia Forestry Commission told WALB News.

The report was unveiled Wednesday at the state capitol, where Gov. Nathan Deal discussed the state's timber industry strengths, including the manufacture of wood heating pellets that are exported to Europe. "I want Georgia to be the leader in the production of biomass," he said. "It will give us the additional revenue we need to sustain our forests and keep them healthy."

The study's research team classified forests based on their characteristics, including the type of forest, the abundance of rare species, scenic visibility and geographic region. They assigned an economic value for each acre based on criteria such as gas and climate regulation, water regulation and supply, pollination, and wildlife habitat. The economic value varied based on these characteristics, ranging from a low of $0 to a high of $8,196 per acre for the forests most important to the state's water systems.

Ninety-two percent of Georgia's forests are privately owned, more than any other state in the country. The state's forests have grown dramatically since the 1970s, when Georgia farms changed their irrigation techniques and began using some of their land for growing trees, according to WALB News.

Here's a video of Leavell explaining what it means to be a tree farmer in Georgia: