Thinning Is In: CALS Helps to Tame Wildfires

Nearly $3.5 billion is spent annually in fighting wildfires that claim lives, destroy homes and scorch the land.

Wildfires today are burning twice as many acres than they were 40 years ago, according to federal officials. Contributing to the devastation in Arizona are dense forests of spindly trees that cause fires to rage out of control.

Thinning the forest is critical in preventing wildfires, and University of Arizona Cooperative Extension, part of the College of Agriculture and Life Sciences, is working with landowners to thin ponderosa pines on their land and implement other fire-wise practices.

"The biggest problem we have is too many trees," said Tom DeGomez, regional specialist and area agent for UA Cooperative Extension in Coconino and Mohave counties in northern Arizona.

"The denser the forest is, the more likely a crown fire is to occur, sweeping through the tops of trees," DeGomez said. "All of the big, devastating fires in Arizona since the Dude Fire in 1990 have been crown fires."

A crown fire advances with great speed along the tops (or crowns) of trees, often independent of a ground fire.

Since 2002, Cooperative Extension has worked with about 525 landowners in Coconino County to thin trees on 2,800 acres, in most cases by removing half the trees.

"This is absolutely preventing forest fires," DeGomez said.

When trees densely populate the land, they compete for water, sunlight and nutrients, making them weak in a state plagued by drought. Thinning trees creates healthier pines that are less susceptible to fire and better protected from the tree-killing bark beetle.

Cooperative Extension agents meet with residents to educate them about the importance of thinning trees and other strategies to reduce the likelihood of dangerous fires. Through federal grants, Cooperative Extension helps landowners in Coconino County with half the cost of tree thinning, which averages about $1,000 an acre.

On average, an acre of Coconino County forest is home to 300 spindly ponderosa pines, averaging about 8 to 14 inches in diameter. With more water, light and room to grow, pines can grow to up to three feet in diameter.

"Our main goal is to get these forests back to where we were in the 1850s, dominated by large old trees," DeGomez said.

Read the rest of this July 13, 2015 UANews article at the link below.