The pecan tree, scientifically known as Carya illinoinensis, is a species of hickory native to the river valleys of the south-central United States and Mexico. This deciduous tree is one of the largest members of the hickory family and holds significant commercial importance for its edible nut. Pecans thrive in warm climates with long, hot summers, leading to widespread cultivation across the southeastern and southwestern US, particularly in states like Texas and Georgia.
The Overall Structure and Shape
Mature pecan trees typically reach heights of 70 to 100 feet, with some specimens growing as tall as 130 feet. They are considered one of the largest native American tree species and can have a trunk diameter of up to six feet. The silhouette is characterized by a broad, spreading canopy, often described as having a rounded or broadly oval crown.
This massive size provides dense shade in the landscape. The large, major limbs grow outward and upward from the trunk in an upright fashion, contributing to the tree’s expansive spread, which can range from 40 to 75 feet. Pecan trees are also known for their longevity, often living and producing nuts for well over a century.
Identifying Leaves and Foliage
The foliage of the pecan tree consists of large, alternate, pinnately compound leaves. Each compound leaf can measure 12 to 18 inches long and is composed of numerous smaller leaflets arranged along a central stalk. Pecan leaves typically have between 9 and 17 leaflets, which are set in an alternating or near-opposite pattern.
Individual leaflets are elongated and lance-shaped with a pointed tip and finely serrated edges. They are a dark green on the upper surface and a paler green underneath. In the autumn, the foliage transforms into a yellow color before dropping, marking the tree as deciduous.
Bark and Trunk Characteristics
The trunk of a young pecan tree starts with a relatively smooth, grayish bark. As the tree matures, the bark develops a rougher texture with distinct features that aid in identification, especially during the winter months. Mature trees develop deep, irregular furrows and ridges that run vertically up the trunk.
The color of the bark is generally grayish-brown to light brown and can appear scaly or interlaced. This rugged, fissured appearance becomes more pronounced with age. This characteristic bark helps distinguish the pecan from other smooth-barked species in its native range.
The Appearance of Pecan Nuts and Husks
Pecan nuts develop inside a protective, four-valved husk. This outer covering begins as a solid, fleshy green shell during the summer months. As the nut matures in the fall, the husk dries out, turns brown, and splits open along four suture lines, starting from the tip.
Once the husk splits, it reveals the nut inside, which is technically a drupe rather than a true botanical nut. The pecan nut itself is oblong or oval-shaped and ranges from about one to two inches in length. The shell is relatively smooth and hard, featuring a reddish-brown color that often has irregular dark brown or black markings.