Like the new Hampton Inn where we stayed last night (all queen beds, small lobby and breakfast area), the just-opened Love's truck stop at exit 54 in Colby (pop. 5,387) carried only two grades of gas, 87 and 89 octane.  When we drove to the adjacent Colby exit to fill up with premium gas, we found a pleasant surprise—a Starbucks store.  Billing itself as the "oasis of the Plains," Colby has the fake palm trees to prove it.  (pictured above)

Completely fueled up, we drove east on US-24 to US-83 and then on to Prairie Dog State Park.  Our first stop was at the prairie dog town within the park.  We were surprised to learn that these little ground squirrels play an important role in the health of the mixed and tallgrass prairies.  Their burrowing systems help channel rainwater into the water table, preventing runoff and erosion.  In the early 1900s, naturalist Ernest Seton estimated that about 5 billion prairie dogs inhabited North America.  The largest colony on record, in Texas, of course, extended 250 miles by 100 miles wide and contained an estimated 400 million prairie dogs.
     

After checking out the pups, we hiked the nature trail, where we found a letterbox and lots of evidence of deer in the park.  Judging by the deer tracks and trails through the grass, the park must be home to sizeable herds, a fact that made us a bit nervous since they are such a haven for ticks.  Although we had hoped to be away from insects by now, we clearly are not.  Today was considerably warmer than we've seen recently, and insects were out in force—flies, gnats, beetles, ladybugs, and probably ticks, though we were lucky enough not to pick up any.  Houseflies swarmed our car every time we stopped and tried desperately to hitch a ride, clingingly hopelessly to the windshield as we drove away until the wind was just too much and they were swept away.
     
To avoid sharing our lunch with the local insects, we ate our picnic at the park in the car.  It took some fast moves to avoid admitting some of the noxious critters in the car after our hike, but just because the doors were closed and the windows shut tight didn't keep the flies and gnats from lighting on our windows and side mirrors, gaping at us as we ate.  We tried to ignore them as we watched the prairie dog activity and listened to news reports about the expected landfall of Hurricane Sandy in New Jersey.
     
Continuing east on US-36, we stopped in Phillipsburg (pop. 2,581), where we located a letterbox near Fort Bissell plus a series of four on a trail near the local medical clinic.  We tracked north for a few miles to visit the cabin where a physician wrote a poem he called "My Western Home" in the early 1870s.  Later his friend set the poem to music, and the tune became a favorite among settlers and cowboys, eventually being selected as the state song of Kansas under its better known title, "Home on the Range." 
   

Based on the size and style of the cabin where the good doctor lived, we'd have to say that the medical field has become significantly more lucrative in the last century and a half.  A campaign is underway to restore the landmark, and in case you're wondering, no, that is not one of our favorite songs.  We visited the location because there was a letterbox hidden nearby.
     

Our primary destination of the day, and the reason we inserted this eastward tack on our journey was a little spot near the town of Lebanon (pop. 218).  In 1918, a scientific survey established that the geographic center of what was then the United States (now the contiguous 48) lies just outside this little town.  A suitable marker was erected there in a little pocket park.  There's even a tiny chapel, so visitors can meditate about the significance of this place.  And now it also has a brand new letterbox.

Finally turning north, we drove from the GCOTUS into Nebraska on US-281.  As we drove through the far southern reaches of central Nebraska, we passed through a couple of hardscrabble towns that time and prosperity have passed by.  Both Inavale and nearby Riverton seem to have a few diehard residents hanging on by their fingernails to towns that are wheezing their last breaths.  In the latest census, Riverton's residents numbered 89.  As an unincorporated area, Inavale's population isn't so easy to determine.   Inavale, where homesteads were transformed to graveyards when the cycle of drought hit in the 1930s, was profiled in New York Times journalist Timothy Egan's compelling portrait of the survivors of the Dust Bowl, The Worst Hard Time.  
   

Our travels ended just before 7 p.m. when we arrived at the newish Fairfield Inn in Kearney, Nebraska, a town where we had overnighted on our way to Yellowstone in 2008.  Tomorrow takes us out of Nebraska and into South Dakota.