English Walnut (Juglans regia) is a cold hardy variety of the kind of walnut that people normally think of when you say walnut - large with a thin smooth shell.
These walnuts are one of the last trees to leaf out in the spring, which helps them avoid late frosts. The leaves are extremely frost-sensitive, but they are very tough plants, and they will regrow new leaves if a late frost kills all their leaves. In their early years, a hard winter may kill them back to the ground, but they will regrow.
These are 1 to 2 foot bare root English Walnut seedlings, 3 years old.
Photo Credit: George Chernilevsky, Public domain, via Wikimedia Commons