A modified Curtiss JN-6 “Super Jenny” airplane spreads lead arsenate dust over catalpa trees in Ohio in a successful experiment to kill sphinx moth larvae. 

C.R. Nellie, an entomologist with the Ohio Department of Agriculture, came up with the idea of combating pests with an airplane. The concept was met with skepticism at first, but eventually a cooperative project was arranged to test Nellie’s idea from the Federal Aviation Experiment Station at McCook Field in Dayton, Ohio.

An outbreak of a destructive moth known as the Catalpa Sphinx in nearby Troy, Ohio, would serve as the test case. The first crop dusting test flight targeted a catalpa grove infested by the moth. Catalpa trees were an important natural resource whose wood was used for building fence posts, telephone poles and railroad ties.

The plane used for the test was called a “Jenny,” the nickname for an ex-military biplane trainer (officially the Curtiss JN-6). Lt. John A. Macready piloted the Jenny while passenger Etienne Dormoy manually dispensed the lead arsenate. Dormoy designed a crude metal hopper with a hand crank that was bolted to the plane’s fuselage. The hopper’s capacity was 32 gallons. On Aug. 3, 1921, Lt. Macready flew from McCook Field to the nearby catalpa grove to conduct the crop dusting experiment. In all, the dusting plane passed the grove six times and distributed about 175 pounds of the insecticide. After the short amount of time it took to apply aerially, less than 1% of the insects remained alive on the catalpa trees after six days of observation of the targeted area. The speed, efficiency and overwhelming effectiveness of the aerial dusting experiment spawned the birth of the agricultural aviation industry.