Do not confuse with
🇪🇺 ◼︎ European black alder Alnus glutinosa
which is also sometimes called black alder. Very-distantly related:
- Not in the same species, family nor order.
- Their fruit are very different (drupe v. cone-like, disbursed by animals v. by wind).
- Their leaves are very different.
- And one is a tree, while the other is a shrub.
Part of
holly genus Ilex,
the only living genus in
family Aquifoliaceae.
Native to 🇨🇦 Canada and 🇺🇸 USA, east of the ⛰ Rocky Mountains.
🗺 Map by county (🇺🇸 USA-48),
🗺 map (North America, Central America). 
Uses by native peoples
(Ethnobotany database)
Ilex hosts caterpillars of 35 species
of butterflies and moths, in some areas.
Use in a small water feature or back patio garden, bloom dates, height, light, moisture, etc. (Pennsylvania). (pages 13, 30, 32 and 46)