January 2007

The DNR communications team works with agency experts to develop the weekly questions and provide the answers. This feature addresses current DNR issues, interesting topics, or the most frequently asked questions from around Minnesota.






Cross-country skiers are required to purchase and possess a pass before skiing on state and Grant-in-Aid ski trails. What is the purpose of these passes?

When cross-country skiers purchase a ski trail pass they are doing more than guaranteeing their enjoyment of the sport in Minnesota. They are helping to maintain the 1,800-plus mile designated cross-country ski trail system at a level that skiers have come to expect. More than half of all trail work is done before the snow flies, such as clearing brush and preparing trail surfaces. The sale of the passes also enables the DNR to work with local units of government and clubs to expand skiing opportunities throughout the state. Even during winters of little snow, skiers that buy either the daily, annual or three-year pass help assure that the trails will always be there. Additional information on cross-country ski passes and skiing opportunities in Minnesota is available on the DNR's Web site: www.dnr.state.mn.us/skiing.

Paul Nordell, DNR cross-country ski pass coordinator


Do I still need an open burning permit for my brush pile even though it is winter?

The snow and cold of a Minnesota winter generally make this time of the year a better and safer time to burn brush piles. And during a typical winter a permit would not be necessary. However, this winter is anything but typical. When there is less than three inches of snow cover, open burning permits are required by law. In communities that regulate open burning, permits are generally required year round regardless of the weather conditions. DNR and local fire departments battled wildfires well into December. As long as a lack of snow pack and warmer winter weather continue, the threat of wildfires exists statewide. If snow eventually arrives, property owners should contact local DNR Forestry offices to inquire about the need for a permit before burning any brush pile.

- Steve Simmer, DNR fire administrative supervisor


People who venture out onto a lake in the winter to fish or enjoy another form of activity may often hear booming and cracking sounds from the ice below them. What causes this? What does that mean?

The groaning and cracking of ice does not necessarily mean that the lake is unsafe. As the temperature changes, there are tremendous forces at work on the massive ice sheet. The forces exhibited by lake ice are similar to those acting on the earth's crust. A sheet of ice can develop fault lines, and sudden shifts along these faults can cause the separated sheets to collide, pushing upwards, creating pressure ridges. These areas can be dangerous, particularly to vehicle traffic as they can cause injuries if someone were to collide with them. The potentially weakened ice underneath these ridges may also cause someone to break through and plunge into frigid waters of the lake below. Shifting ice can also push up along shorelines and form large, leaning ice heaves and potentially hazardous conditions. Parents should be careful that children do not play on or around these dangerous ice formations.

- Greg Spoden, DNR Division of Waters


Concerns over global warming continue to build. What affects do global climate changes have on fish and wildlife management?

Global climate change will alter the physical environment that strongly determines habitat suitability for all species. Changes in the hydrologic cycle may include increased frequency of strong storms and potential declines in soil moisture. These changes will in turn affect distribution of plant species and potentially increase runoff of nutrients in to surface water bodies. Tall grass prairies may shift to short grass, and boreal conifer forests may shift to maple-basswood or oak savannas. Winterkill, an important natural phenomenon for shallow lakes, will decline, and thus fish may become more pervasive in shallow lakes that are important for waterfowl production. Direct effects of temperature will allow warm water fish such as bass and bluegills to increase in abundance and expand their range, while coldwater species such as lake herring and lake trout are in danger of being extirpated in a number of Minnesota lakes. Cool water species such as walleye and northern pike may increase in northeastern Minnesota, but decrease in the southern part of the state.

- Don Pereira, DNR Fisheries research supervisor


The DNR is pushing the Archery in the Schools program. What is this program all about?

The Archery in Schools Program has three prepackaged components that make teaching target archery in K-12 classes very safe, effective and easy, particularly for inexperienced archery teachers and students. The gear is state-of-the-art and designed to fit every student in the class. The training and instruction aids provided to teachers enable them to set up ranges in their gymnasiums and safely teach new archers proper form and technique consistent with the USA Olympic archery program. Finally, the curriculum and lesson plans enable teachers to integrate the program into a rigorous academic environment. Archery is usually the most popular physical education unit because every student can excel, regardless of natural athletic ability. Archery is lifetime sport that students can enjoy for decades.

- Kraig Kiger, DNR shooting sports coordinator


DNR Question of the Week Archive