Mockernut Hickory

Take a closer look at this tree, and examine one of the leaves. Mockernut hickorys have compound leaves. In contrast to simple leaves, a compound leaf is made up of multiple leaflets. This species of hickory typically has 7 leaflets per leaf, but sometimes can be 5 or 9. The leaflets are arranged in a pinnate fashion, meaning that there is one leaflet at the tip and other leaflets paired on each side of the leaf. The entire leaf can be up to 20 inches long, while the individual leaflets can be up to 8 inches each. The mockernut hickory’s Latin name is Carya tomentosa. This name comes from the latin word “tomentum” which translates to ‘covered with dense short hairs’. If you flip the leaf over to look at the paler undersides of the leaflets, you can see dense short hairs which helps with the identification of this native tree. In the spring, the leaves will appear green and as the seasons progress to fall, the leaves turn yellow before dropping.

The mockernut hickory reproduces with flowers. Each tree is monoecious, meaning that there are both male and female flowers present on each tree. The male pollen-producing flowers appear as long catkins, which look like little cat tails that are 4-5 inches long and stem from the branches of leaves from the previous season. The female flowers look like small spikes and branch from buds of the current year. The pollen is wind dispersed, meaning that the pollen moves from catkin to short spike due to wind in order to produce flowers. After fertilization occurs, female flowers produce seeds inside of fruits, which are dispersed by squirrels and birds between September and December. Trees can take 25 years to grow before they produce fruits. The most viable seeds come from trees that are between 40 and 125 years old!  Since the seeds take so long to become viable, the crops produced are sporadic, so it can be said that mockernut hickory undergo sporadic reproduction.The fruit produced encloses a small edible kernel. This kernel is wrapped in a thick reddish-brown husk that splits from the middle to the base.

Like the other members of the Juglandaceae or Walnut Family, the mockernut hickory tree’s seeds are also called nuts. Visually, the nut from this tree is a green color when first developing, and then it becomes light brown as it matures into the fall. The nuts maintain an off-circular shape. The nut will range in size from 1.5 to 3 inches from its furthest points, and is one of the heaviest seeds produced from the hickory species. Although the nut feels thick, there is only a very small edible portion inside, which some may argue is not worth breaking into the nut to get to. However if you were to reach the edible portion, the taste can be comparable to a pecan. The amount of nuts produced is dependent on the weather during nut growth. Squirrels will eat the nuts before maturation, or while they are still green. Chipmunks and squirrels help move the nuts around, which helps explain why the trees are present in so many different areas.

Thank you for taking time to learn about one of the many amazing trees that Rowan has to offer. If you would like to check out other mockernut hickory trees located on campus, you can walk along the path towards the townhouses, which is to the left if you are facing the Student Center.  If you would like to learn more about similar trees on campus that bear edible nuts, I recommend finding other members of the Juglandaceae Family, like the pignut or shagbark hickory trees . I encourage you to explore trees from different families, too. All of the tree species on campus add to Rowan’s diversity!

These resources are a product of Dr. Sara Wright’s Plant Diversity course in the Biological and Biomedical Sciences Department. My name is Harley Rosenzweig, and I will earn my Bachelor of Science in Biological Sciences in 2023 I plan to pursue a career in the health professions. You can read more about me and the Mockernut Hickory below.