title: Ammonia volatilization from senescing leaves of maize.
abstract: Ammonia release by plants growing in normal air is reported. Contrary to observations made at high ambient ammonia concentrations, corn plants did not absorb ammonia in normal air but released it as they senesced, even while photosynthesizing actively.
authors.forename: G D
authors.initials: GD
authors.lastname: Farquhar
authors.forename: R
authors.initials: R
authors.lastname: Wetselaar
authors.forename: P M
authors.initials: PM
authors.lastname: Firth