The attraction of bridges
PHOTOS BY GARRY BRANDENBURG — The Iowa River flows placidly under a former old wrought and cast iron bridge in today’s winter time scene at Three Bridges County Park. The riffles showing on the water are created by the remains of a long ago dam that once spanned across the river. That limestone block dam, when in full operation in the late 1800s and early 1900’s, could divert water into a south shore mill where water pressure would turn the water wheels to grind farmer’s grain crops. The site was an important component of early Marshall County history. Today there is a new foot bridge on the bluff top nature trail. This bridge replaced its former suspension bridge that was destroyed by the wind storm of two years ago. Constant maintenance of nature trails is an ongoing task for Marshall County Conservation Board staff.
Bridges, whether on roadways, or nature trails, assist in the way people get from point A to point B. We tend to take them for granted until one breaks, is destroyed, or causes inconvenience when it takes a long time to construct a replacement. Bridges across the Iowa River are hugely important for commerce and efficient transportation of goods and services across what would otherwise be a roadblock of Mother Nature’s doing.
Marshall County’s early history has many stories of how our pioneer forefathers struggled with horses and buggies to get from one place to another. Luckily a horse could just wade through shallow water.
The occupants of a buggy or carriage however may have ended on the other shore with wet feet. Frequent high water flows or severe flooding complicated the scene a lot, so it is no surprise that building bridges over rivers, streams or even small creeks presented challenges both physically and financially.
In many of the county parks areas, nature trails are cleared, maintained, and routed in such a way as to allow hikers access into an area as they explore the natural world of plants and the animals that use adjacent habitats. And in almost every case, a nature trail route eventually comes to an obstacle to the preferred places where people will be encouraged to walk.
That obstacle could be a very small stream, a gully, or just the contours of the land. Building a bridge in many instances will enhance the trail users experience.
At Three Bridges County Park, the high bluffs above the floodplain have always been an attraction for people. Trails to get to the bluff top were mere footpaths at first, and after the Marshall County Conservation Board made its first land acquisition in November 1960 for the thirteen acre parcel, plans were developed for the park to encourage public use.
As a river access site, it filled the bill. Fishing is and remains an outdoor recreation pursuit at this park, but fishing is not the only attraction of this site with its wooded bluff top.
There are also extensive exposures of bedding planes of limestone along the entire north-south orientation of the park. Limestone was close to the original land surface at the time of settlement activities. So began the quarrying operation to remove the overburden top soil, expose the limestone, and blast, cut and remove those stones for any needed building project. The Marshall County Courthouse has as part of its makeup limestone blocks from Three Bridges.
From a geologic perspective, the limestone layers (bedding planes) have a story to tell of long ago Mississippian age shallow warm salt water oceans.
All kinds of saltwater marine plants and animals lived in that ocean. Over extremely long periods of geologic time, the skeletal remains of those animals and other sediment materials were built up.
They compressed into more and more deposits. As the great oceans receded multiple times, dry land and glacial primitive soil deposits buried the limestone, only to be erased and repeat the process all over again.
Quarrying at this site has exposed the limestone layers to investigators and scientists, and within those limestone bedding planes can be found crinoid stem segments, a few shark teeth, brachiopods and many other ocean marine fossils.
Limestone was so important as an early construction product that getting the stone to another work site required roadways and bridges, and so it was to be. Access to this quarry site was both from the north or south on a county roadway.
For a short time a railroad spur line was built to enable hauling the stones to other places. There were two small wooden bridges to the north side of the Iowa River, plus the Iowa River iron arch bridge, and together these three bridges gave the area its name that persists to this day.
Those two small wooden bridges have long ago succumbed to the ravages of Iowa River flooding events and they have been removed. The north side county road has been closed. The iron arch bridge itself remains but is unsafe for any vehicle traffic.
It remains open only to pedestrian use. That iron arch wagon bridge was built in 1885 at a cost to the county of $3,295. In May of 1998, it was placed on the National Register of Historic Places.
The newest bridge is the 100 foot long suspension footbridge. This footbridge is tough, strong and well built to last many years. It leads one along and to the hiking trail of the bluff top. This footpath has long served as a great-get-away for people wanting to explore and exercise in
an outdoor setting.
Follow the foot trail all the way to the south end of the park where a series of steps allows one to return northward by following exposed limestone features. The hiking trail at Three Bridges County Park is enhanced tremendously by a bridge to the natural world.
Enjoy it when you walk across it.
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Deer hunters have been busy this week as first season ended on Wednesday with a statewide total off take of over 30,000 more animals. Add the off take prior to the first firearms season of 30,000 gives a total slightly over 60,000 so far.
Second firearm season began on Saturday, Dec. 10. By that season ending on Dec. 18, add another 40 to perhaps 50 thousand more deer will fall to hunters. The firearms seasons are pivotal to taking enough deer away from the population for management purposes.
I checked with Iowa DNR’s Tyler Harms, PhD and Biometrician, regarding total estimated deer numbers in Iowa pre-season. He noted that lots of observations by field biologists, game wardens, seasonal spotlight surveys over standard routes, and bow hunter observation records are very helpful in making meaningful estimates of overall deer population counts.
It is not a precise counting system since any wildlife census is limited by the mobility of the critters and invisibility within habitats. Yet in spite of all the obstacles, a fairly accurate count of deer statewide can be determined.
Population models take into account all the above. Historical trend lines help a great deal and by the time another deer season rolls around for 2023-24, Harms plans to have a very good idea of what Iowa deer population numbers will be going into next fall.
As for the deer number estimates for Iowa before any deer hunts took place this fall, his staff feels that number is about 600,000. By the time hunters have finished their times afield, between 100,000 and 120,000 deer will be harvested.
That leaves a postseason population of 450,000 to 500,000. An annual harvest of deer is one good trend line component in his work. Starting in January of 2023 and ending in May 2023, Dr. Harms and his team will have pretty well settled on what strategies and management methods will be needed to accommodate workable regulation proposals for the fall deer seasons of 2023.
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A point of information to make for deer hunters regards the waiting time before an official measurement can be made of an antler set. One will hear 60 days a lot.
Yes, that is only one part of the drying period that is considered standard operating procedure by both of the established measuring methods of the Boone and Crockett Club or the Pope and Young Club. Both organizations use the same scoring methodology.
Here is the note to remember: scoring officially may only take place after a cleaned skull or skull plate has been maintained at room temperature and humidity for a minimum of 60 days. Therefore a deer’s antlers may not be scored if on the 61st day, it was just brought inside from a cold and frozen environment, or a home freezer, or farm machine shed. Sometimes a hunter will finally get around to cleaning the skull by boiling it many days after the deer was killed. The 60 day rule can start all over again at zero if the skull is re-immersed into a water bath for another cleaning cycle.
Sixty day minimum drying time is required to allow the bony plates of a deer skull, or any other antlered or horned big game animal, to stabilize. There will be a very tiny bit of shrinking as drying takes place.
It takes as much time to carefully measure a deer less than 60 days as it does to wait until the measurer is assured this requirement has been met. Measurers for B&C or P&Y are careful to conduct their free services according to the rules these organizations have established.
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A deer antler measuring seminar will be held on Feb. 23, 2023, a Wednesday evening, from 5:30 to 7:30 p.m. at the Grimes Farm and Conservation Center. This free program does require pre-registration before Feb. 17 just so Naturalist Emily Herring can plan for the total interest hunters will have in attending and a limit to how many people can be accommodated. Official scorers will be available to help work through the process of correctly taking the data on antlers. Call the MCCB at 641-752-5490 or for text only messages use 641-758-9777.
Deer antlers have another source for scoring coming the first weekend in March at the Iowa Deer Classic Show to be held in Des Moines at the Iowa Events Center.
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Garry Brandenburg is the retired director of the Marshall County Conservation Board. He is a graduate of Iowa State University with a BS degree in Fish & Wildlife Biology.
Contact him at:
P.O. Box 96
Albion, IA 50005
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- PHOTOS BY GARRY BRANDENBURG — The Iowa River flows placidly under a former old wrought and cast iron bridge in today’s winter time scene at Three Bridges County Park. The riffles showing on the water are created by the remains of a long ago dam that once spanned across the river. That limestone block dam, when in full operation in the late 1800s and early 1900’s, could divert water into a south shore mill where water pressure would turn the water wheels to grind farmer’s grain crops. The site was an important component of early Marshall County history. Today there is a new foot bridge on the bluff top nature trail. This bridge replaced its former suspension bridge that was destroyed by the wind storm of two years ago. Constant maintenance of nature trails is an ongoing task for Marshall County Conservation Board staff.
Outdoors Today
Bluebirds and Bluebells = Spring
Northern Pike eggs now in Spirit Lake hatchery
Robins adapt to March’s variable weather
Sportsman’s sale at Ikes April 5-6
Wildlife taxidermy art on display March 23
