I learned about “the fever” last week. Not from a doctor, but from folks who love old tractors. Nelson Trambly of Campbell, an All-Nebraska Tractor Drive coordinator, said in a Hub video (see it at kearneyhub.com) that the fever is an overwhelming “gotta have it” feeling that comes when a tractor guy or gal sees a certain tractor.

The heat rises with a realization that if one tractor is good, one more and then one more is better.

That fever was obvious last Friday when I caught up with the group and their 70 or so tractors during a lunch break at Audubon’s Rowe Sanctuary southwest of Gibbon. The two-day event based in Minden featured Friday’s drive that included Lowell, Rowe and Axtell, and Saturday’s drive to Campbell.

“Fever symptoms” seemed mild in some drivers, more extreme in others.

Some said their tractors were special because they drove similar ones as youths. Others said they have multiple examples of their favorite makes, models, brands and colors.

Car, truck and motorcycle collectors seem to have a similar fever. The memory part is strong, but their strain also has an “always wanted one, but couldn’t afford it before” factor.

Collectors of everything imaginable have at least slightly elevated temperatures.

I’m more of a keeper than a collector. I have bookshelves filled with travel and event souvenirs, plus boxes and drawers full of negatives and prints from my film camera days. I rarely, if ever, spend time with the old souvenirs or look at photo albums, and I know they have no value to anyone but me.

I also know I never could replace them. Is that a fever symptom?

On the History Channel’s “American Pickers,” pickers Frank and Mike often deal with collectors who have high, almost debilitating, fevers.

The pickers mostly go to places where people have said they’re ready to sell because they need the space and/or money, they’re getting older or they have no family member interested in their stuff. At bargaining time, some change their minds and others set unreasonably high prices — emotional value, not market value.

On a recent episode, the pickers dug through ceiling-high piles in a huge building to select a few small buried items to bring outside to the owner. That’s when those pieces, which the man likely didn’t remember owning, became priceless parts of his collection. They were not for sale, he said, and must be returned to the exact places where they were found.

People who love activities — sport, art or craft, travel, cooking, hunting, fishing, hiking — experience similar fevers.

I read Monday’s Hub story about Bill Giffin’s love of cycling and his current mission to complete the coast-to-coast Trans-American Bike Race. I was in awe of his ability and ambition. However, only other long-distance cycling enthusiasts truly can understand why he’s doing it.

The same is true for tractor guys, car enthusiasts, and other passionate collectors and doers.

Few people understand why an always-cold me will park my car on rural roads in mid-March, roll down the windows and sit a good long time to watch and photograph sandhill cranes in cornfields.

I plan to go to the Fort Kearny State Recreation Area Sunday morning for a pollinator week event on what sounds like a nice day for a walk with my camera around my neck.

If I see a winged thing drop onto a pollinator plot plant, I’ll put my camera to my face and expect my heart to beat a little faster with excitement. I don’t think that’s a sign of “the fever,” but I won’t be surprised if my hands get a little sweaty.

Lori Potter is a Hub staff writer.