The USDA has access to thousands more weather stations now than in the past. That, combined with 30 years of new data, led to big changes in its hardiness map of cold winter temperatures in Kansas.

In other words, growers should be aware that an exceptional cold snap could still buck the USDA’s adjusted map.

Based on 30 years of data, about half of the country has shifted a half-zone warmer on the map.

However, the USDA hasn’t linked this to climate change.

It wrote in a news release that the new map partly reflects efforts to record temperatures in more locations.

Several thousand more weather stations contributed to the 2023 map – 13,412 stations compared to the 7,983 that provided data for the 2012 version.

Additionally, the agency said that the lowest winter temperatures in each area can vary significantly from year to year.

“Map developers involved in the project cautioned against attributing temperature updates made to some zones as reliable and accurate indicators of global climate change,” the agency said in its release, adding that studying climate trends usually requires longer-term data.

Other groups, such as the nonprofit Climate Central, say the changing growing zones fit a trend of global warming caused by carbon pollution in the atmosphere.

If the trend continues, Climate Central says, this could expand the range for high-value crops such as oranges, but it could also allow some crop pests to spread north.

Celia Llopis-Jepsen is the environment reporter for the Kansas News Service. You can follow her on Twitter @celia_LJ or email her at celia (at) kcur (dot) org.

Do they become “snowbirds” and relocate to warmer climates until spring? Do they hibernate like bears? Or do they continue to do the jobs they do so well, waiting for spring and fresh plantings to support?

In regenerative and biological farming, the fate of soil microbes during the winter months plays a crucial role in shaping the overall health and productivity of the soil. Traditional farming practices can undervalue soil health post-harvest, but regenerative approaches prioritize maintaining an active and diverse microbial community, even in the winter.

As the temperatures drop and the growing season ends, the microbial activity in the soil changes. Studies show that microbial activity in agricultural soils increases in the fall when compared to other growing seasons–likely due to an increased level of nutrients and soil organic matter from crop and plant residue post-harvest. Throughout the wintertime, or non-growing season, microbial activity and composition are thought to be stagnant, but stable. An increase in microbial activity occurs after the thawing of frozen soils and can be linked to the freeze-thaw cycle that colder climates experience.

During the colder months, soil freezes over, preventing air diffusion and creating anaerobic conditions for the microbial communities. This occurrence alters the soil community structure. In turn, this change causes an increase in denitrification, respiration, and production of greenhouse gases, which are trapped under the frozen layer. When temperatures begin to rise, the soil begins to thaw, enabling oxygen to enter the soil. This process provides labile carbon and other nutrients to the soil, which increases microbial activity and biomass. Additionally, when the soil thaws, the trapped greenhouse gases are released into the air. This exact dynamic between microbial activity and the FTC is still being debated due to different soil properties greatly affecting freeze/thaw rates and as researchers use different methodologies, making it difficult to compare results between studies.

The incorporation of cover crops is a key practice in regenerative agriculture during the winter months. These cover crops serve as a protective blanket for the soil, preventing erosion and providing a habitat for beneficial microbes. The roots of cover crops, left in the soil after harvest, create a network that sustains microbial life. Additionally, the above-ground biomass of cover crops can act as a carbon source, feeding soil microorganisms even when the primary crops are not actively growing.

The winter period becomes a time for microbial communities to thrive beneath the surface, breaking down organic matter, cycling nutrients, and enhancing soil structure. This activity sets the stage for a vigorous start to the next growing season. “A plant needs a tremendous amount of energy as it breaks dormancy. We should be building that plant up as much as we can, so it comes out swinging strong next season,” says August York, a noted agronomist based in California. “Farmers need to give it more momentum, so it goes into next year at a faster pace.”

Jim Ladlie, who holds a doctorate in crop science and has been in the agriculture industry for more than 30 years, says that when soils are fed well after harvest, growth emerges sooner and more vigorously the next spring, leading to a robust start to the season. He also said that for anyone who fertilizes with products that feed the microbes, soils and plants remain strong throughout the winter, as proven by field studies conducted by Rodale Institute, The Ohio State University, and the U.S. Department of Agriculture. By promoting the health of these microbial populations, regenerative farmers ensure that the soil remains alive and resilient, ready to support plant growth when conditions become favorable again.

In contrast to conventional thinking that might view winter as a dormant period for the soil, regenerative farming recognizes it as a crucial phase in the continuous cycle of soil regeneration. The proactive management of soil health during winter pays dividends in the form of improved nutrient availability, reduced pest and disease pressure, and overall enhanced soil fertility come spring. This holistic approach to soil care during the winter months aligns with the overarching principles of regenerative agriculture—working with, rather than against, the natural processes that sustain life in the soil.

There’s nothing like the pine scent of a fresh-cut Christmas tree during the holiday season. The aroma and beauty of the outdoors are welcome in homes, but a freshly cut Christmas tree may harbor something within its branches that’s not so welcome.

It’s not likely consumers will come face to face with a squirrel like Clark Griswold did in “National Lampoon’s Christmas Vacation,” but dealing with a variety of insects and other arthropods isn’t out of the question.

Real Christmas trees are grown outdoors and serve as a home for overwintering insects and other arthropods. These tiny creatures can remain on the limbs or under the bark after the tree is harvested and brought indoors, said Andrine Shufran, Oklahoma State University Extension specialist and director of OSU’s Insect Adventure.

“In the fall, insects find places to overwinter or lay eggs in preparation for the winter weather,” Shufran said. “It’s not uncommon for a tree to harbor ants, bark beetles, aphids, beetle larvae, praying mantises or even spiders. They look for micro-climates where humidity is high and the temperature is warm.”

While they may not be apparent before the tree is cut down, these insects become active when they warm up inside the home. Shufran said a praying mantis can lay enough eggs to fill two to three egg sacs, which contain up to 200 eggs each. Look for egg sacs on the undersides of branches, and if one is found, cut off the limb and place it in a protected area outside — it should hatch in the spring. Protecting some species of insects is important because they’re beneficial and eat invasive species that can harm a landscape.

“It’s important to remember that the insects or spiders that might be on the tree can be annoying to have inside the house, but they’re harmless,” she said. “If a family happens to find some insects on the tree, take it as an entomological learning opportunity. Talk about the life cycle of insects and beneficial insects versus harmful insects. The insects can be vacuumed up if necessary to get rid of them.”

In addition to insects, some trees may have a good amount of pollen on the branches. Even though most of it will fall off during the shaking process before taking it home, consumers may consider rinsing the tree once they get it home.

David Hillock, OSU Extension consumer horticulturist, said for those visiting a tree farm or cutting their tree on open land, inspect the tree for signs of insects.

“Most insects aren’t active at this time of year, so they may be hard to spot,” Hillock said. “The foliage should look clean, not sticky or like an insect has been sucking on the leaves or shoots. Families don’t want to wake up and find aphids on the floor or covering the gifts under the tree.”

When purchasing a freshly cut tree at a tree farm, make sure the tree stays on the shaker for 20 to 30 seconds. This not only removes loose needles but also most of the insects on the limbs.

“If consumers cut their tree and don’t have access to a shaker, tap the trunk of the tree on the ground multiple times to disperse loose needles and insects,” Hillock said. “Another idea is to use a leaf blower or compressed air to get rid of loose needles and insects. Also, shaking the branches over a piece of white paper before cutting it down can expose possible insects.”

Once the tree is home, water it properly to help keep it as fresh as possible through the holiday season. A fresh tree can use up to a quart of water per day for each inch of diameter on the cut end. For example, a tree with a 3-inch trunk diameter can use up to 3 quarts of water per day.