By JOHN HOLLAND
Almond growers aim to keep their customers healthy by keeping salmonella and other germs out of the orchards.
Many try to do this by excluding rodents and other creatures that can track germs onto the orchard floor, where the nuts lie after being shaken from the trees.
But many growers also like to maintain at least some ecological diversity on their farms. They might do this with grassy cover crops between the trees, or hedgerows at the orchard's edges.
Trouble is, these mini-habitats could nurture the very animals that growers want to keep out so the crop doesn't become tainted.
"Human pathogens are unfortunately carried by these birds and squirrels and so forth," said Merle Jacobs, associate director for industry relations at the Almond Board of California, during an orchard tour near Ripon last week. "There's always a balance: Are you mitigating one problem and adding to another problem?"
The Modesto-based board put on the tour at Travaille and Phippen Inc., an almond grower and packer, for about 50 people from the industry, government and the media.
The event showcased several environmental efforts, most of which do not clash with food safety. Growers, for example, have been chipping rather than burning pruned branches. They use harvesting equipment that stirs up little dust, and they guard against water pollution.
But food safety has returned to prominence thanks to several disease outbreaks in the past year, notably E. coli in Salinas-area spinach and salmonella in peanut butter from Georgia.
The Central Valley almond industry, which provides about 80percent of the world supply of the nuts, had salmonella problems of its own at few orchards in 2001 and 2004.
Part of the safeguards are at the packing plants, where employees keep their hands and equipment clean, and where pasteurization increasingly is used.
On the farm, the measures could include avoiding manure-based fertilizer and monitoring irrigation water for pathogens. And, maybe, excluding the critters.
"All animals, wild and domestic, including mammals, birds, reptiles and insects, are potential sources of contamination," said an Almond Board brochure prepared for growers.
That approach could be tough on a farmer seeking overall ecological health through cover crops, hedgerows and the like. These plantings can improve thefertility and water-holding capacity of the soil. They also can attract insects that prey on pests, reducing the need for pesticides.
Eco-friendly farming also can help growers fend off regulations and create a positive image among consumers of the crops.
More research recommended
Mark Cady works with farmers to plant hedgerows as a program director with the Community Alliance With Family Farmers, based in Davis. He urged the Almond Board to do more research on whether wildlife really can transmit pathogens to nuts.
Cady, who was not at the orchard tour, said the concern about germs is understandable.
"One small slip can damage a market," he said, "and with the almond market being so big and so valuable, people are risk-averse."
Manure is another example of how sustainable farming can be at odds with food safety. The waste is a renewable source of fertilizer, available from nearby dairy farms, unlike synthetic fertilizers made largely from fossil fuel. But the Almond Board warns that manure can transmit pathogens to nuts.
Jacobs mentioned yet another conflict: Reduced pesticide use could mean less control of navel orangeworms, an almond pest that can make the nuts susceptible to aflatoxins, which can sicken humans.
But Nick Gatzman, who helps manage the Travaille and Phippen farm, said he has kept the worms under control with little spraying. A key step each winter, he said, is removing almonds that lingered on the branches after harvest, denying the worms their favorite spots.
Gatzman said his trees could go as much as a decade withoutspraying for orangeworms, thanks to the winter nut removal and other measures. All this is cheaper than the old practice of spraying on a regular schedule, he said.
"You used the diazinon and the Lorsban and you did it every year," he said. "We found that you don't have to do that."