Ask Professor Produce

What does IPM mean? I see that phrase on food labels from time to time, and I assume it's a farming practice of some kind. But can you fill me in on what it stands for and what it means?

Integrated Pest Management. Sure it might sound like the name of a slumlord corporation, but really it's a system of agriculture that uses a variety of means to control weeds and pest insects, with the ultimate goal of reducing negative environmental impacts.

The perfect person to help explain this to us is Harry Hoch of Hoch Orchards. Not only does Harry bring us some of the tastiest Macintoshes and Haralsons on the market, heÕs literally written the book on IPM (along with entomologist Henry Fadamiro) for Minnesota apple growers for the Minnesota Department of Agriculture.

Due to our humid, rainy climate in the spring, a plethora of pests target Minnesota apples, making our orchards prime candidates for IPM methods. Coddling moths, apple maggots, and apple scab are the Axis of Evil that Harry fights every season. The apple scab fungus, in particular, could produce a new infection every 3-5 days if the springtime weather were rainy and warm, meaning that a conventional apple grower could spray synthetic fungicides every week. An organic grower using natural sulfur and copper pesticides would have to spray every 3-5 days. But heavy organic fungicide use can affect soil flora, burn leaves, and cause the fruit to russet. "This can make it very difficult to get high quality apples," says Harry.

To fight apple scab the IPM way, Harry uses several high-tech tools to delay using fungicides on his apple crop. Using a sophisticated analysis offered by the Minnesota Apple Growers Association, apple scab spore samples are taken from apple leaves in several sites around the state and examined under microscope. In this way, Harry can determine ahead of time when apple scabs' spores will mature, which helps coordinate other IPM efforts.

He also uses a Data Logger that tells him when conditions are ripe for apple scab throughout the season. By gauging temp (every 30 minutes) and leaf wetness, Harry can determine when conditions are ripe for infection, and if need be, he'll apply a synthetic fungicide. Harry uses the newer classes of fungicide that only require a few ounces per acre, one of which is a mushroom-based fungicide (fight fungus with fungus, I always say). Harry will typically apply 3-5 fungicide applications per season while conventional apple growers may apply 5-10 or more per season.

Some of Harry's other IPM techniques are far more low-tech - like mowing. "I'll mow every other row [in the orchard] to enhance the habitat for beneficial insects," says Harry. This leaves small nectar-producing plants that adult predator insects can feed upon. These "beneficial" predator flies and wasps then lay eggs whose larvae feed upon coddling moths and other insect pests.

Harry also put up 35 birdhouses in 25 acres of the orchard. "A pair of bluebirds or wrens can eat a lot of insects."

All of these strategies are used to delay the use of broad-spectrum insecticides and organophosphates, two toxic compounds that are commonly used in conventional apple growing. "I do the best I can to avoid these two classes of chemicals," says Harry. "You can tell your readers that so far [as of July 9], I haven't applied any this year."

I'm a long-time co-op shopper; I'm a member at both Mississippi Market and the Wedge, and I really enjoyed the letter from Kevin Aylward about Amy's Kitchen in the June/July newsletter. Could you please pass on to him what a fan of Amy's soups I am?

I cook almost everything from scratch - almost everything organic - but sometimes, one's in a hurry and I found out for myself that Amy's has the best-tasting soup on the shelves - and baked beans, too!

It delights me even more to know that it's an independent, family-style company. I try my best to support such companies and I will surely continue to patronize Amy's products. I congratulate them and want them to know how much I appreciate their efforts on the consumers' behalf! I'd be grateful if you could pass this message on to Kevin.

-Thanks, Jan Forsberg