I have never witnessed deer browsing much on members of the Willow Family (Salicaceae). Rabbits and mice, however, will girdle young trees by eating the bark in the winter. Beavers also seem to like branches of these trees for winter stores. This family is made up of two genera, the Willows (Salix) and the Poplars (Populus).
Willows. I will be honest. I can’t tell willows apart. The flowers were too small to differentiate in my field botany classes, so everything was referred to as Salix sp. (meaning we knew the genus, but not the species). I called all trees Black Willows (Salix nigra), which was probably accurate most of the time where I grew up. I referred to all Willow shrubs as Pussy Willows (Salix discolor) which was probably less accurate. While I grew up with Black Willows that always had their feet in water, I think that the Missouri Willow (Salix eriocephala) is probably a better native tree for most landscapes. It grows quickly, lives a little longer, and doesn’t need constant water. It would be a great tree for stabilizing a stream bank. While Weeping Willow (Salix babylonica) is a popular choice, I actually prefer the form or our native willow trees over the Weeping Willow. I think the native trees have more character.
The Pussy Willow (Salix discolor) is a great shrub, and doesn’t require a wet area. There are tons of cultivars out there, and many are attractive. In this case, using a native will make your landscape unique. Pussy Willow is one of the first things to bloom while winter is still entrenched in the north. I remember cutting the first blooms that I would find on my boyhood tromps and taking them home to my mother. She always seemed to brighten. To her, pussy willows were a signal that the days would soon get longer and sunnier.
The Poplars, or “popples” as my Grandpa called them, are better known as Aspens to most. These are beautiful trees with very interesting light gray-green bark. The buds are an important food for many birds. I love them because they shimmer in a slight breeze. The leaf petiole (or stem) is flat and at a ninety degree angle to the plane of the leaf, so leaves seem to flutter. As a kid, I could predict the weather by watching the leaves. Those leaves turn a brilliant yellow when the elk begin to bugle. (By the way elk, rodents and rabbits eat the bark of aspens, but I have never seen deer eat their bark.) As a pioneer, they love lots of sun and can tolerate poor soils. While they may not live for centuries, they will live longer than most homeowners who plant them. Give them some room and they will form a dome shape colony (or clone) of genetically identical individuals. For sentimental reasons, I prefer the Quaking Aspen (Populus tremuloides) slightly more than the Bigtooth Aspen (Populus grandidentata). Both are attractive trees and more interesting to me than the Lombardy Poplar (Populous nigra) that is often seen planted in yards.
(Incidentally, Tulip “Poplar” or Yellow “Poplar” (Liriodendron tulipifera) is in the Magnolia family, and isn’t a poplar at all.)