State’s Almond Growers Seek to Clear the Air

Almonds are one of California’s most valuable crops, worth $1.5 billion a year. But harvesting them comes with a high price -- thousands of tons of dust.

The dust, kicked up by the shaking of trees and sweeping of orchards, creates an airborne health hazard in one of the country’s most unhealthy air basins. In response, farmers are taking aggressive actions to make sure less dust is added to the stew of pollutants hovering over the Central Valley, ideal for almonds with its cold winters and long growing seasons.

“Understand that dust is a huge problem for us,” said Jack Efird, who also farms walnuts, prunes and grapes. “I’ve been trying to do everything I can to minimize dust.”

Efird, his brother Russel and fellow growers received a directive this summer from state air officials to control dust during the annual harvest, which typically runs from late July through October.

Getting the crop to market -- this year, just more than 1 billion pounds of nuts on 550,000 acres -- takes three steps.

A machine grabs and shakes each tree, loosening the ripe nuts. Another piece of equipment then goes along each row, raking in the nuts that are within reach and blowing the rest to where they can be reached. A third engine drives by each tree, sucking up the almonds and blowing off most of the leaves, debris -- and dust.

This process raises nearly 41 pounds of microscopic dust particles each time an acre of almonds is harvested. A single orchard can be harvested as many as three times.

By comparison, wheat raises 5.8 pounds of harmful dust for each acre harvested and cotton 3.4 pounds, according to the California Air Resources Board.

The Almond Board of California is financing research to measure just how much dust comes off the orchard floor and what kinds of equipment and practices could best help reduce the plumes of fine powder kicked up at harvest time.

“We want to give growers as many options as possible, depending on their situation,” Colleen Aguiar, the almond board’s industry relations manager, said from the board’s office in Modesto.

Already, growers are using new equipment with more-efficient air systems; limiting the number of passes made through orchards for each harvest; harvesting more often at night, when winds are lighter and moisture levels are higher; and watering the roads that surround orchards.

Some practices are within reach of all farmers, said Teresa Cassel of UC Davis, who has been measuring dust in orchards since 1995.

Examples, she said, are driving slowly on dusty roads and trying to harvest two types of almond trees at once so the machinery doesn’t have to go up and down each row several times.

Some farmers already are using a new type of sweeper that keeps dust to a minimum.

One is grower Scott Hunter, who recently watched one of the machines as he stood between rows of Butte and Padre trees.

The sweeper shoots some dust but nothing like the plumes that almond harvesting has been known to raise.

“This industry provides food and jobs for people all over this valley,” Hunter said. “We’ve got to find ways of meeting the needs of the farmer and the environment.”