Beavers were certainly back-country work horses….were used in NZ for aerial topdressing during the fifties and sixties.
The large floats create considerable drag and would increase stalling speed and coupled with a turbulent airflow [rotor] in lee of a ridge…not good.
Had a friend in NZ who realized during take-off in a new floatplane[cessna] he was running out of lake and the rising bush in front;..decided in a split second to close the throttle after getting airborne and dropping back into what lake was left and finishing up in the bush….he walked away from a damaged but reparable aircraft.
We lost a few early fletcher aircraft doing slow speed turns in lee of ridges.