I’ve had to pay close attention to trees this year.
While working on a bird study, I have to record vegetation at sites where my birds are singing. This required a little more tree identification than I am used to. I was able to make progress with a new field guide, “The Sibley Guide to Trees” by David Allen Sibley. It re-familiarized me with trees I already know and helped me get a grasp on some that I hadn’t looked at much.
Let’s start with the characteristic trees of the Cross Timbers post oak (Quercus stellata) and blackjack oak (Q. marilandica).
Post oaks typically have a cross-like shape to their leaves and have the underside with some fuzz. They typically grow up to 40 feet tall.
Blackjack oaks can be similar but have less lobed leaves that are almost triangular. Blackjack leaves also have tiny points at the tip of the lobes. Another differentiating characteristic is their often darker bark and the way their branches hang.
The blackjack branches often are growing all up the tree and droop downward. Because of this abundance of low branches, they are excellent habitat for wildlife.
We have several other common oaks.
Red oaks have deeply lobed leaves with pointed trips. Red oak classification appears to be fairly uncertain, with many species that often interbreeding and sometimes considered the same species. I usually call ours the Shumard Oak (Q. shumardii). They are found in river-bottom (riparian) areas and on top of rocky hills.
Burr oak (Q. macrocarpa) is naturally a riparian species in our area. The leaves are big with deep, round lobes. The acorns’ very deep cup, covering almost the whole nut, is very distinctive. Many of the smaller branches and twigs have “winged” bark sticking out.
Live oaks (Q. virginianica) are different from the previous oaks by virtue of their evergreen foliage. They keep their shiny oval all year, only shedding them briefly in the spring. They look like they don’t drop them, though, as they usually keep the old leaves until the new ones have grown.
Hackberries are another common and easily identified tree. According to my tree guide, we have several species in the genus Celtis, but they are all extremely similar. The leaves are round at the base and taper to a point, with a smooth or slightly toothed edge. They have small, reddish-brown fruits. The most distinctive feature of the tree is the very warty bark.
Although it is often considered a weedy species, it is great for birds and other wildlife because of the berries.
It is also a host plant for several common and beautiful butterflies. These include the Hackberry Emperor and the very similar Tawny Emperor, both of which are brown-spotted. They are very bold and will land on you to lap up your sweat. It is a funny feeling to have a tiny butterfly proboscis tapping over your skin.
Another butterfly whose larvae feed on the hackberry is the American Snout. I adore snouts. They are hilarious with what looks like a long nose. This is actually part of the mouthparts called the labial palps, and they don’t eat anything with it (they still eat with the proboscis). The snout is part of the butterfly’s “I am a dead leaf” camouflage. It looks a bit like a leaf stem when combined with the mottled brown underwings.
Next month I’ll go over additional common trees in our area. Meanwhile, during these hot days of summer, when it can be so quiet, take a look at our beautiful trees. It’s amazing how varied and elegant they are upon close inspection. They are both good habitat and food for other creatures and fascinating in their own right as well. You never know what wonders you will find!
The next monthly field trip on the Lyndon B. Johnson National Grasslands will be Sept. 1 and Oct. 6. We will depart at 9 a.m. from the Forest Service District Office in Decatur. For information, contact Mary Curry (see below) or the Forest Service District Office at (940) 627-5475.
Claire and Mary Curry are nature enthusiasts based in Greenwood. If you would like to contact them, please e-mail them at firstname.lastname@example.org.