Exceptionally Dry Winter Leaves Dolores County Trees Stressed, Roots Drying

“This winter has been exceptionally dry across the Four Corners, and in many places there isn’t even snow on the ground, which means our trees may actually be more stressed than they look.” That assessment hits home for Dolores County, where low winter moisture can weaken roots during dormancy and set the stage for dieback, pests and higher water demand in spring.

Even while aboveground branches appear dormant, roots can dry during prolonged cold, dry spells, and “that can lead to dieback later in the spring and summer.” Biologists warn that the stress is not only immediate hydraulic strain. “Trees respond to drought in several ways,” said George Koch, a biology professor at Northern Arizona University. “As conditions dry out, they start to close up tiny pores on their needles and leaves called stomata. That helps slow water loss to evaporation but prevents the intake of carbon dioxide, which plants need to photosynthesize, Koch said.” Reduced photosynthesis and depleted root reserves leave trees more vulnerable to insects and disease.

Forest entomologists are already sounding alarms. “This is super dry for us, so if it continues there’s going to be a lot of concerns I’m sure,” said John Anhold, a forest entomologist with the U.S. Forest Service, referring to increased susceptibility to bark beetles and other pathogens that can accelerate tree mortality.

Regional drought monitoring shows the problem spans the Four Corners. “The latest drought maps show drought and abnormally dry conditions have taken hold of significant portions of the Four Corners region of Arizona, New Mexico, Colorado and Utah,” and, “With the exception of Colorado, the other states are worse off now than they were at this same time last year.” Locally, Northern Arizona “missed out on a white Christmas,” a shortfall that officials say will affect municipal water sources and supply balance going into next year.

Dry fuels are also reshaping forest management. On the Coconino National Forest, crews have done “low-intensity understory burns on about 50 percent more acreage than normal, said Victor Morfin, the forest’s fuels specialist.” Morfin and others shifted operations in October to night burns when relative humidity was higher “to prevent the fire from getting too hot.” The Forest Service paused prescribed burning over the holidays but “if the weather continues to be warm and dry, Morfin said the agency will ramp up burning again in January.”

For Dolores County residents, practical steps can reduce acute stress on trees. Local guidance urges homeowners to water trees even in winter: “With warmer temperatures expected this weekend, highs in the 50s here in Cortez, it’s a good window to give trees a deep drink.” The recommended approach is plain: “The general rule is to water one to two times a month when there’s little snow cover and the ground isn’t frozen. Water during the warmest part of the day, and go slow and deep so moisture reaches the roots. Young trees and evergreens need extra attention, since they lose more water to dry winter air. A layer of mulch around the base can also help hold in moisture and protect the soil.” As the guidance notes, “It may feel strange to water in January, but in a dry winter like this, it can make a big difference come spring.”

What comes next for Dolores County depends on snowfall and precipitation in coming weeks, pest monitoring outcomes, and water managers’ responses. Residents should prioritize slow, deep watering for vulnerable trees, mulch where practical, and watch public notices from the Forest Service and county water officials as prescribed-burn plans and supply forecasts evolve.