Unmanned aerial vehicles (UAVs) equipped with spreaders are increasingly used for applying slug pellets. Compared to conventional ground vehicle-mounted-equipment, UAV spreaders can be deployed under wet soil conditions without causing damage to plants and soil. The results of field trials show that the deposition patterns achieved by a commercial UAV spreader are characterized by coefficients of variation of about 30–40 %. For comparison, two standard single- and double-disc spreaders mounted onto ground vehicles were tested according to a similar protocol. They achieved coefficients of variation of 23–40 %. In nearly all tests, the relative amounts of slug pellets collected beyond the chosen working width are above 3 ‰ of the total amount applied.