The biggest Jeffrey pine.

Bill Chapman probably noticed but did not realize the significance of the sweet vanilla smell of the pine tree he was tapping for pitch. Pinus jeffreyi and Pinus ponderosa are so similar that little else would distinguish them to the casual observer. Chapman collected the pitch and soon learned a valuable, if painful, lesson in natural history. On that fateful day in 1867, near what is now Paradise, California, he fired up his turpentine still and unknowingly added pitch from a Jeffrey pine rather than the very similar and normally used Ponderosa pine. Seldom has a case of mistaken tree identity been so consequential: The still exploded. The volatile Jeffrey-pine pitch was later analyzed and found to contain a form of heptane so pure that it was eventually used to define the zero end of the octane rating system for gasoline. At the pump, it would undoubtedly be called Jeffrey Pine Super Knock Supreme.

Ironically, this contribution to the development of the internal-combustion engine became an environmental boomerang. Photochemical smog from car exhaust has been implicated in the destruction of thousands of acres of Jeffrey pine and other tree species. The cost of driving our cars has gone up in more ways than the numbers we see at the pump.

Fortunately, the biggest Jeffrey pine grows deep in the Sierra Nevada, where its pleasing vanilla or, to some noses, pineapple scent is relatively untainted by car fumes. Although the champ is signposted, you may still have trouble telling other Jeffrey pines from their "ponderous" cousins that some believe smell like butterscotch. But there's no penalty if you get them confused--as long as you stay out of the turpentine business.