The farmers had just finished work and were sitting by a fire when the strike happened, according to tribal elder Malik Rahat Gul.
"Some of us managed to escape, some were injured, but many were killed," said farm laborer Juma Gul.
Reteurs reported that there may be more farmers missing:
Haidar Khan, who owns the pine nut fields, said about 150 workers were there for harvesting, with some still missing as well as the confirmed dead and injured.
A survivor of the drone strike said about 200 laborers were sleeping in five tents pitched near the farm when the attack happened.
In a statement, Colonel Sonny Leggett, the spokesman for the U.S. campaign in Afghanistan, said the attack was aimed at "Da'esh (IS) terrorists in Nangarhar" province.