FIRE is a natural resource management tool. Fire used correctly at the right time and right place assists in killing off woody vegetation. Since the growing points of grasses and prairie forbs are below ground and insulated from the heat, fire does no damage to the plant. Once spring rains happen, added to longer days with the warming of soil temperatures occurs, the prairie will be invigorated for another growing season.
The Marietta Sand Prairie got started in 1983 with the initial 17 acre acquisition. Several years ago the remainder of the sandy soil based farm area was added with the help of a Resource Enhancement and Protection (REAP) grant, Wildlife Habitat Stamp grant, local matching grant initiatives and many private donations. Pheasants Forever chapters in central Iowa contributed a healthy sum of money to the project.
Speaking of pheasants, during the controlled burn, several cock pheasants were heard in the distance. It is nice to know that there are survivors in this area where grasslands for nesting and feeding are maintained. Fire at this time of the year is way ahead of any hen pheasant nest site selection. When only a portion of a prairie complex is burned, the majority of the existing old growth remains for the pheasants to hide in.
T-R PHOTO BY GARRY BRANDENBURG
Controlled burns for prairie land management are taking place in Marshall County. Today’s view shows an area of approximately 20 acres that was successfully burned on April 12 at the Marietta Sand Prairie. Using fire to burn off last year’s grassland growth is one way to invigorate the grasses and speed their ‘green up’ after spring rains. American Indians on the plains used fire extensively to ultimately lure bison and elk onto green spaces where they could be hunted.
Controlled burns are a multi-step process. First, fire lanes of about 12 feet wide were closely mowed last fall. This divides a prairie into segments for a multi-year rotational burn plan. Those mowed pathways are low on fuel load and therefore provide a check point for control crews to watch a progressing fire back burn. Second, burns work best on days with light winds and wind from the 'right direction' for that segment. High wind days are not the time to burn grasses. Third on the list is having a crew of people that are experienced in prairie fire management. Fourth is the setting of backfires that slowly burn into the wind. This keeps the pace of the fire slow. Once the backfire has consumed the entire fuel load in a wide swath, the final step of a head fire can be set. This burns with the wind, is fed more oxygen by the wind and swiftly races across the old grasses in amazingly tall flames. Spectacular yet ephemeral mini tornadoes of flames, smoke and dust can and do erupt in an instant and disappear just as fast.
This year's Sand Prairie burn area encompassed the eastern portion of the prairie that lies adjacent to the bluff line of the Iowa River floodplain. On the rolling uplands is the site of a fen, a very rare and unique type of wetland that gets its moisture from a slow and steady underground upwelling. The fen has many documented special plants, several of which are on Iowa's rare or endangered list. Botanists will delight in a revisit to the fen this summer to view a multitude of special plants. The fen may be tiny but it is an important component of Iowa's prairie landscape.
DUCKS use wetlands in the north central part of North America, a region that got its landform shapes of undulating small hills and water filled depressions from past glacial episodes of our earth's history. Biologists call it the Prairie Pothole Region. It ranges from Manitoba and Alberta to the Dakotas, part of Montana, Minnesota, Nebraska and northern Iowa. Of the top 10 common ducks taken by hunters each fall, six have their highest nesting densities in the PPR. Another name for the PPR is 'duck factory' for the millions of shallow water basins it contains. As our winter subsides, the icy grip is released and water refills the places that ducks need for another year.
Our Iowa River is running low right now, kind of unusual for us during the spring season. All can change quickly if enough rain falls in a short period of time within its watershed. We've seen it before and only time and circumstances of the future will write the history book or our next drought or next flood. So goes the moods of Mother Nature.
The Iowa River floodplain and the river itself within Marshall County has an average slope of about 2.2 feet per mile. The elevation of the river at the Hardin/Marshall county line is about 920 feet above sea level. When the river enters Tama County just over 29 river miles later, it is at 850 feet, a loss of about 70 feet. To anyone on the river this summer, it will appear to be a lazy stream offering us plenty of time to enjoy a fishing hole or admire its tranquility from a canoe. Contrast our river with the following.
Flooding on the Red River as it flows north between Minnesota and the Dakotas is another example of geological circumstances impacting human life. Flooding has even closed portions of the Interstate highway in North Dakota. Why? Several factors come into play. First, the Red River flows north at the same time as spring thawing and a receding snow line moves north. Second, ice jams can easily happen as ice fragments from the south meet solid ice on a still unopened river in the north. If ice meets ice, then water pressure below the ice spreads out onto the land. Third, the Red River is all that is left today of a once huge ancient glacial lake names Agassiz created by dams of unmelted glacial ice that collected the melted water from the glaciers. The Red River is about 9,300 years old, too young geologically to have carved a significant valley in the floodplain. This floodplain has a gradient of 5 inches per mile in the Fargo to Halstad region. It gets even flatter at 1.5 inches per mile in the Drayton to Pembina area. This lack of slope contributes to the potential for extensive flooding. If you want to see truly flat land, travel along I-29 in North Dakota. You will be driving on the highway built at the bottom of an ancient glacial lake.
Iowa SPRING TURKEY seasons are underway. Several local folks have taken this big game bird home to the freezer. Others are still trying to get close. More than 40,000 turkey hunters will disperse across Iowa between now and the end of May. Any turkey taken by a hunter must be reported via the reporting process either by phone or on a computer. Accurate reporting is vital to biologists and managers. Reporting a turkey kill also avoids a ticket from a conservation officer. Take note.
If you are interested is seeing a prairie burn listen to your radios and watch the T-R website during the week of April 18. Marshall County Conservation Board will host a night prairie burn out at Green Castle Recreational Area one mile south of Ferguson at 7:30 p.m. Come watch prairie management in action. The scene will be spectacular as the fire lights up the night sky. The exact date for this program is dependent on weather conditions and will be determined on short notice. Call the Marshall County Conservation office at 752-5490 for more details.
For your funny bone: You know you are in a Redneck Church if ... A member requests to buried in his four wheel drive truck because "It ain't never been in a hole it couldn't get out of."
Garry Brandenburg is a graduate of Iowa State University with BS degree in Fish & Wildlife Biology. He is the retired director of the Marshall County Conservation Board. Contact him at PO Box 96, Albion, IA