nutlet broadly wing-margined, the body comprising less than half the width; NOT [nutlet wingless, merely margined]

nutlets narrow-winged or with leathery margins; NOT [nutlets mostly broadly winged]

Viridis: Answers to key questions in Budd's Flora and Flora of Alberta leading to this species. 

	shrubs; NOT [tall shrub or small tree]
	leaves shining; NOT [leaves dull]
	leaf buds sessile; NOT [leaf buds stipitate]
	leaf buds covered by imbricate scales of unequal length; NOT [leaf buds covered by 2 or 3 scales of nearly equal length]
	flowers developed with the leaves on the twigs of the season; NOT [flowers developed before the leaves in early spring]
	nutlet broadly wing-margined, the body comprising less than half the width; NOT [nutlet wingless, merely margined]

Alnus: Answers to key questions in Budd's Flora and Flora of Alberta leading to this genus. 

	staminate flowers usually three in the axils of the catkin bracts; NOT [staminate flowers solitary in the axils of the catkin bracts]
	stamens 4; NOT [stamens 2]
	pistillate catkin elongated; NOT [pistillate flowers few in a short, bud-like catkin]
	bracts of pistillate catkins becoming thick and woody; NOT [bracts of pistillate catkins thin, 3-lobed]
	bracts of pistillate catkins persistent; NOT [bracts of pistillate catkins deciduous]
	fruit a nutlet in the axil of a catkin bract; NOT [fruit a nut enclosed in a leafy, hispid involucre with a long beak]
	nutlets narrow-winged or with leathery margins; NOT [nutlets mostly broadly winged], NOT [nuts wingless]