November 2003





Humans and fish are similar in that they rely on the senses of taste, smell, sight, hear and touch to live and cope with their surroundings. However, fish also have a sixth sense. What is it?

Fish have a built in motion detector called the lateral line, a row of tiny holes that run along each side of the body. The sensitive hairs inside each hole help detect the location and direction of vibrations in the water. This is especially important to anglers. The sound and movement of bait in the water attracts attention. Once at an angler's lure, fish will use their other five senses to determine if the bait is something that sounds like, feels like, looks like, smells like and tastes like something they might usually eat. While the lateral line helps fish find a meal, it also helps them avoid becoming one too. The lateral line also helps a school of fish swim together without bumping into each other.
Jenifer Matthees, DNR Aquatic Education Supervisor


Now is the time of year when most property owners are considering pruning their trees. Removing unwanted branches improperly and at the wrong time of the year can stress and damage the tree. When and how should trees be trimmed?

The best time of the year to prune your trees is in the fall after the leaves have fallen from the tree. Most of the energy that the tree has produced over the year has been sent down to the roots for storage, so removal of unwanted branches will have a lesser impact on the health of the tree. When removing a branch, you want to make sure that you don't cut into the branch collar of the tree (tissues where the branch meets the trunk), and don't remove more than 1/3 of the live crown of the tree. The USDA Forest Service has a pamphlet that describes proper pruning techniques. It is available on their website at USDA Forest Service
Bill Glesener, DNR Forester, International Falls


Erosion is an on-going problem facing many landowners with property along Minnesota's lakes and rivers. Are there ways to help control or stop the "disappearing" of the shoreline?

The best defense against shoreline erosion is natural vegetation. If the vegetation has previously been removed or destroyed, property owners could consider attempting to re-establish the natural buffer zone using native plants. This buffer zone will also help protect lakes and rivers from overland run-off. Another option available to landowners is riprap with an adjoining vegetative buffer strip. The best time to do the work would depend on the type of project - autumn for riprap, when water levels are generally lower; and spring-time for replanting native vegetation. Permits are generally required with either type of project, so it's recommended property owners check ahead before beginning. Brochures and other information about shoreline protection and erosion control projects can be found on the DNR's Web site at Shoreland Management
Kevin Bigalke, DNR Shoreland Habitat Coordinator


A new state law prohibits the use of all-terrain vehicles (ATVs) in wetlands on public and private property. Will deer hunters be able to use an ATV to retrieve a downed deer in a swamp or wetlands area?

The new law does not provide an exemption for retrieving big game from wetlands. However, we do expect that this law will require some public education, as is the case with any new law. In most circumstances, DNR conservation officers will issue verbal and written warnings for operators violating the new rule. Officers will still issue citations for those violations that involve intentional and/or serious disregard for wetland resources, public lands and waters. For those hunting in these types of areas, it is possible to quarter a deer for easier retrieval, as long as the head remains attached to one of the quarters until the deer is registered.
Bill Spence, DNR Division of Enforcement