Prairie management tool = fire
FIRE can be a friend or foe, a tool for good, or if improperly attended to, a hazard. Wise use of fire by trained personnel that have attended fire school know when to burn and when not to burn. Usually a short window of time exists each spring from about mid-March through April when last year’s growth is still dry. Soon new shoots from the soil surface growth points will make it too hard if not impossible to even start a managed fire.
That is why one will see smoke in the sky at various points now through mid April on land sites all over Iowa, or the Midwest for that matter. One must consider the fact the entire midsection of North America from the Rocky Mountains east toward Indiana and Ohio and then south to the Gulf Coast has lots of natural grasslands. Forests existed along major streams and tributaries. However between the lineal stream patterns was a lot of open country, grassland country, and in historical times, periodic fires. Estimates of how much tall grass prairie existed prior to settlement is about 140,000,000 acres!
Iowa’s original landscape of 56,272.81 square miles, pre-settlement, was estimated to be about 85 percent tall grass prairie equal to 47,832 square miles, 13 percent forests which equals 7,315 square miles and water at 2 percent that adds another 1,126 square miles from a combination of all border rivers, interior rivers and streams and natural glacial lakes carved out long ago by moving ice fields and filled with the melt water from those ice masses. These figures help paint a picture of Iowa’s land between two rivers. This was long before settlement began its slow and inevitable landscape modifications beginning in the mid 1800s. In Iowa now, less than one-tenth of 1 percent of the landscape has native undisturbed prairie grasslands to explore or serve as scientific remnants of what once was.
As natural rainfall amounts decreases as one goes west from the Mississippi River, tall grass prairies transitioned to mid-grasses and further west, short grass species. These are still native grasses but some more adapted to drier conditions. Fires, however, knew no boundaries.
Prairies are complex ecosystems, a community of many animals and plants. Classifications of grasslands by botanists give them names mesic, dry or wet. Marshes and savanna communities are often found near prairies. This blending of habitat types make it difficult to say where one ends and other begins. One local example can be found at the Marietta Sand Prairie Preserve located three miles southwest of Albion. Prairie grasses dominate the uplands but transition at several points into boggy wetlands, sedge meadows, and even a very rare fen. Fens have a unique setting where upwelling water from underground creates special conditions for very unique plants.
Fires happened from several sources. One: Lightning from storms if all conditions are right. When a fire begins in the right place and fanned by strong winds, it can travel fast. Some pioneer historical accounts tell of prairie fires traveling faster than a person could ride a horse away from it. Fires were feared by settlers at the time. If caught in the open grassland, there may have been nowhere to hide, or now where to run. Some folks found shelter in ponds, river backwaters or rivers or streams. Once the fire passed, it was back to the business of surviving.
Two: Native American Indian nations knew the benefits of fire. Their observations over many centuries taught them many lessons. A lesson that worked was fire set on purpose in the right place at the right time to clean off old tall grass prairie thatch. Left behind was a blackened landscape at first, but far from a dead landscape. Just below the soil surface, grass roots and growth points were not hurt in the least. The dark soil surface now absorbed the sun’s rays to warm the land. Spring rains nourished the soil and soon a new crop of lush tender green prairie grasses and forbs grew with renewed vigor. This new growth was the equivalent of bison pasture management, long before any settlers ever found the east coast of North America.
Bison, elk, deer and pronghorns plus a bevy of other wildlife benefit from periodic and sporadic grassland fires. Fresh grazing was a key factor to attract and hold bison and other plains game. For the Native Americans, that is equivalent to bringing the grocery store to you instead of having to look far and wide to find the animals. Fires also tended to burn in patches or segments depending upon the natural fuel load on the land. Some fires thus burned very hot and took everything down in its path. If the fuel load was thinner due to soil type variations or lack of grass, maybe the fire burned low, slow and maybe even extinguished itself. Another natural fire break were stream corridors lined with trees with little if any combustible fuel, or just wet or soggy soils. Poof, these fires went out.
Native wildlife were adapted also to fires, however the fire began, natural or by native peoples. They moved away from the hazards of walked through thin fire lines out onto the just burned landscape. Some sought relief in waters of rivers or just crossed rivers. Small mammals had burrows below ground where heat was not a factor. Later they would re-emerge to a darkened land but found seeds and other foods easier to find. Of course predators in the air or on the ground had easier pickings for a time until the new grasses grew tall again.
Prescribed burns are one of the management tools of modern day landowners and in the case of conservation areas, teams of people tasked with knowing when and where to burn for the long term benefit of the land’s vegetation. Only select portions of an area may get burn management this year. Next year a different area gets fire, and the third year the remainder. Then the cycle is repeated. Conservation managers like to leave at least two-thirds of any one site unburned. This helps maintain a more patch-like variability to the site. It is a system that works. Fire is a good grassland/prairie management tool.
q q q
The IOWA TAXIDERMY SHOW is taking place at the Regency Inn at Marshalltown. Public hours are today from 12-5 p.m. and tomorrow from 9 a.m. until noon. There will be a wide variety of critters to see. The detail and effort put into these displays is awesome. Come and see for yourself what these artists and experts in their trade can do. Admission is free and you get to vote for a People’s Choice Award.
q q q
UNION GROVE STATE PARK is located between Garwin and Gladbrook in northwest Tama County. This 110-acre surface lake will soon be refilling, if it rains enough. Work on improving the dam and its spillway outlet are near complete. A new gate value system has been installed, in part to keep rough fish from entering. Shoreline armoring with rip rap (large stones) has been accomplished. Other improvements were also undertaken with the lake bed dry. Soon water will refill the site. And the next step involves floating dredge machinery to dig out and pump silt into designated holding areas. Dredging is expected to deepen the lake overall by about 3 to 4 feet. It will take time to do this specialty contract work. So public patience is asked in the meantime. New watershed land projects to the northwest of Union Grove will help immensely to capture or filter silt out of runoff waters.
q q q
How many of us have had this happen? It is that helpless feeling when you are holding a level full hot cup of coffee in your hand and you start to sneeze.
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 50005.