Thaddeus’ Ruminations

A Few Degrees Makes a Difference

By Thaddeus Barsotti
Published: February, 2007 

I will always remember my mother pointing out the gently sloping hills in the Capay Valley, golden and painted with shadows from the sun and oak trees that sporadically embellish the landscape. She pointed to the spots where the hills were flat enough to farm, yet, still well above the valley’s floor – spots the cold air would roll right off of, as she used to put it.

It is no wonder my mother taught the value of a few degrees. In the frost of 1988, she lost a young Satsuma Mandarin orchard — meanwhile, the orchard just a few hundred yards up the hill survived. This was an expensive lesson and surely one a parent would not want her children to learn the hard way.

Many orchards and farmers are feeling the effects of the cold snap that just covered the state. It is estimated that 75 percent of California’s citrus crop was lost this year. The percentage of the orchards that were killed will be determined this spring. The orchards and crops that survived were in abnormally warm micro-climates or at an elevation that escaped the cold air below.

Cold air is much denser than hot air. Farmers pay particular attention to this when selecting a location to invest an orchard sensitive to freezing temperatures. We were interested in growing citrus. These tropical trees, quite frankly, were never intended to survive Northern California’s winters. But Citrus trees are really only in danger during the extremely cold periods, but those occasional freezing temperatures are death – briskly disguised.

When the temperature creeps below the freezing point, the cold, dense air pulled down by gravity displaces warmer air to higher elevations, resulting in what is called an inversion layer. It may not seem like much, but these few degrees can determine whether an orchard dies or lives another season.

When I drive around our valley, I still recognize those perfect spots my mother pointed to — high enough to scare away the cold and tame enough to farm. I can see what the orchard looks like to others driving by — a green patch in the quilted layers of grasses, shadows and trees that make up the hills. It crosses my mind that those spots are important for only a few weeks of the 20 or so years that a Citrus tree produces fruit; but the importance of those moments are paramount events in an orchard’s life. Those moments are what allow the orchard to continue to work for the farmer who placed them there.

2 Cups diced sweet citrus (any)

1 Cup fennel bulb; thinly sliced

Simple vinaigrette;

1/4 Cup olive oil

1/4 Cup balsamic vinegar

Salt and Pepper to taste

Mix ingredients, chill and serve.