Tree of the Week: Native Pecan (Carya illinoinensis) Part Two

A blindingly hot summer day poignantly reminds us of the presence and indisputable value of a mature tree. Our tree of the week, the native pecan, is one such specimen. It's pictured in the photo above, working in concert with other native gems to offer a reprieve, however brief, from those intense midday rays. In our previous post, we talked about its known history, growing conditions, bark and fruit. This week, we are recording specifics about those shade-providing leaves.

Our native pecan (Carya illinoinensis) has a favorable reputation as a shade tree. It's handsome and a hardy native with large leaves that provide significant shade. However, in the fall, invectives against the tree might be hurled when these big leaves begin to pile up on the lawn.

A few leaves were snipped for inspection. Theys are long, each measuring approximately two feet in length, including the petiole.

Native pecan leaves are pinnately compound. Each leaf is composed of an odd number of dark green lanceolate-shaped leaflets. The leaf under examination possesses 15 leaflets, which vary in size. This leaflet measures 6 inches in length.

Another leaflet measures 7 inches in length.

Leaflets have pointed tips and serrated margins.

Underneath, leaflets are pale green.

Leaflets have an asymmetrical shape.

Native pecan petioles are long and feel fuzzy.

While still attached to the tree, petioles alternate along the twig.

Twigs are fuzzy, too.

You can find additional information about this particular native pecan here.

Tree of the Week: Native Pecan (Carya illinoinensis) Part One

This time we have a project spread out over two weeks: a thorough look at one of our native pecans (Carya illinoinensis). It's pictured center.

A precise age hasn't been determined for this native pecan. Some time before 2004, it volunteered in this spot, on the north side of the Fitness Center. Based on the arboretum catalogue, we presume it to be a hybrid from the neighborhood. But which other species did the native pecan hybridize with? Hopefully in the future we can resolve this question. This week we are recording information about its growing location, bark and fruits. Next week we will take a look at the leaves.

This native pecan has been successful in a relatively dry location. It grows towards the bottom of a steep slope. During heavy rains, water quickly runs down the slope, without accumulating in this location, and until last year, this spot has been without regular irrigation. Native trees are often quite hardy.

Rough, flaking, light gray bark covers the trunk.

Unfortunately, the handsome trunk bears the depredations of the yellow-bellied sap sucker (Sphyrapicus varius). The native pecan is not alone. We seem to have a healthy population of sap suckers. See Quercus lyrata and Ulmus rubra.

Looking up the trunk we see significant damage to branches as well. Large portions of bark have been removed from multiple limbs. Who is the culprit here?

We do not have photographic evidence to prove anything, but nonetheless we will move forward with accusations. It's the squirrels! They have a reputation for causing severe damage to tree bark. Reasons for the behavior are under investigation. Check out Joe Boggs' article on that subject (here).

Now, let's turn to the good news: we are seeing immature fruits on this volunteer pecan tree! This is of special note because the mature fruits will give us further clues concerning the lineage of this volunteer.

Will these fruits ripen into delicious pecan nuts? Or will we end up with something flattened and bitter, resembling the fruit of the bitter pecan (Carya aquatica)? Hopefully these fruits will ripen over the course of the summer so that we can get to know more about this volunteer.

Consult the following for more information about our native pecan:
United States Department of Agriculture
Louisiana Plant Identification and Interactive Virtual Tours (LSU AgCenter)
University of Florida (IFAS Extension)

Carya illinoinensis