Juglans cinerea was created in 1759.
The scientific name is the Juglans nigra
"butternut tree", "juglans cinerea" and "white walnut
The scientific name for butternut hickory is Carya cordiformis.
Leptophobia cinerea was created in 1867.
Castilleja cinerea was created in 1883.
Eurhodope cinerea was created in 1879.
Nepa cinerea was created in 1758.
Eburia cinerea was created in 1959.
Oenopota cinerea was created in 1842.
Arctosa cinerea was created in 1777.
Coprinopsis cinerea was created in 1774.
If you mean the Butternut tree ther are two. One is Juglans cinerea of the walnut family. There is also Caryocar nuciferum a Brazillian tree with hard durable timber.