The pecan tree is among the most valuable of any of the cultivated species of plants that comes from North America, according to the "National Audubon Society Field Guide to Trees." The nuts are edible and sweet, with the tree's wood prized for its excellent grain and strength. The leaves of the pecan tree as well as the fruit are easily recognizable. Both are subject to insect pests and the leaves can fall victim to specific diseases.
Pecan Leaf Identification
The pecan tree has pinnately compound leaves. The leaves are a combination of a central axis (rachis) from which a number of leaflets emerge. These leaflets grow out on both sides of the rachis, with one single odd leaflet at the end of the rachis. Anywhere from nine to 17 leaflets occur on a pecan leaf, with the slightly sickle-shaped leaflets being in the 4- to 8-inch long range and as wide as 2 inches; the rachis can be from 12 to 20 inches in length.
Pecan Nut Identification
Pecan fruit develops from the flowers, which are small and come in male and female varieties on the same tree. The female flowers produce the fruit, which has an elliptical shape. The shell has four ribs and they are thin, splitting open upon ripening to reveal the fruit inside. The nuts can grow to be as long as 2.5 inches.
The pecan leaves have a dark greenish-yellow color, with the underside's shade just slightly paler than the top surfaces of the leaves. In autumn, the leaves change to yellow before they fall off, a process that can create quite a mess under the tree. The nuts of the pecan, encased in a dark brown husk, are a lighter hue of brown.
Nuts and Wildlife
Pecan nuts have very high protein content and an equally high fat content. The Florida Forest Trees website notes that this makes them an important part of the diet of certain animals, such as squirrels, raccoons, opossums and foxes. Many birds will also eat the nuts, and the leaves are important forage for species such as the white-tailed deer.
Diseases and Pests
The leaves of the pecan tree are vulnerable to a number of diseases. These include spot anthracnose, a malady brought about by a fungus that makes small lesions appear on the leaves. A disease known as pecan scab can adversely affect the trees, as lesions will develop on the veins of the leaflets. Different insect pests will munch on pecan leaves. The forest tent caterpillar, the sycamore lacebug and the walnut caterpillar will all eat the leaves, reports the United States Forest service website. The pecan weevil bores into and eats the nuts, ruining them when it does so.