Coaz was scientifically active in the areas of forest botany, topography, meteorology, and glacier and avalanche research. He described Larix X marschlinsii Coaz, noted in Krüssmann as a hybrid between L. kaempferi and L. russica that came from the Tscharnerholz Forest Nursery, near Morat, Switzerland in 1901Krüssmann, Gerd, Manual of Cultivated Conifers, Timber Press, p. 162. (the species is now considered a hybrid between L. decidua and L. kaempferi). He was awarded an honorary doctorate from the University of Bern in 1902.
