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Spinning Your Quarters on the Prairie

There's an interesting phenomenon called the coin rotation paradox. Begin with two quarters and place them on a table with one showing heads, or George Washington, and the other tails, or the eagle. Now glue the one showing the eagle to the table and place the other one upright so it is touching the glued one. Like this:

Next, rotate the George quarter all the way around the eagle quarter so that it stays in contact the whole time and doesn't slip. Here's the question- how many times will George spin around as he makes his journey?

Now a second journey for George. Determine the circumference of the eagle quarter (its diameter times Pi), lay that circumference flat on the table in a line, put the George quarter upright at the start of that line. Like this:

Next, roll the quarter along the line and see how many times George spins before reaching the end of the line. Note that this flat line is the same distance as when it is configured into the circumference of the quarter.

On the prairie (and in life in general!) the amount of work done to accomplish the same goal can be different with various approaches. Doing it one way means you only have to do it once and you're done. Another way might require twice the effort. For example, if a patch of buckthorn seedlings is foliar sprayed, but it is done at a suboptimal time, such as a dry period when the plants are relatively dormant, it may not be effective and require a second spray and twice the time and effort. Or if a prairie is burned before clonal species such as sumac are taken care of, it may require twice the effort (or more!) to control the clone. Finally, using the wrong herbicide at the wrong time to cut and treat an invasive woody species can lead to wasted effort. You get the point.

Now back to the quarters. In the first example where one quarter is rotated around another fixed quarter, George spins TWICE as he makes his trip as per this link:,once%20around%20the%20inner%20coin.

In the second example, George spins only ONCE. Keep in mind that this is the same distance. We might say, the same goal is achieved with half the effort.

So, when you are thinking about restoring that enticing remnant prairie, think it over carefully, research various methods of restoration, and do your best to take a straight path to your goals to avoid unnecessarily "spinning your quarters"!

Good resources to consider are Friends of the Blufflands, Prairie Moon Nursery, as well as the leadership of the local chapter of The Prairie Enthusiasts called the Coulee Region Chapter. The Prairie Enthusiast website,, also has good information, including under the FAQ and Planting a Prairie tabs as well as under the blog tab. Good luck!

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