Professor Steven Goldsmith

Autumn in north Texas

Autumn is progressing in north Texas, but not that fast. We have had a couple of “rain events” and associated cool snaps, some of the trees are beginning to turn, and giant ragweed is in full bloom. But we still have strings of pleasant, even warm days between the cool snaps, the pool is still warm enough that I can swim across and back (although the water gets your attention!).

 

 The fall wildflowers are just winding down. See last year’s post for some information about late summer wildflowers in north Texas, and look for an upcoming post about the fall wildflowers.

 

On the warm days, there are plenty of insect pollinators visiting the fall wildflowers. When most people think of pollinators (if they ever do think of pollinators, which they should), they think of honeybees. Certainly honeybees are important pollinators, and they serve us by pollinating many of our fruit and vegetable crop plants, but they also pollinate many wildflowers as well, and so contribute to healthy plant populations, which in turn contribute to “ecosystem services.”

There are plenty of other insect pollinators, including wasps

 

This is a member of the family Vespidae, which includes the eusocial paper wasps and yellowjackets.

It is hard to tell from this image, but this is a member of the wasp family Tiphiidae, which includes a large number of solitary wasp species (sometimes referred to as flower wasps because the adults feed on nectar). These wasps are by and large parasitoids, and the larvae feed on beetle larvae.

Bumblebees are among the fall pollinators

 

As are butterflies

like this painted lady, or this hairstreak

 

And flies

 

But probably honeybees are the most efficient. They have a host of adaptations that make them good pollinators. The body is covered with bristles that trap pollen, and there are the specialized bristles on the tibia of the third legs called the pollen basket, that are used to comb through the body bristles and collect the pollen. The honeybee's mouthparts are referred to as "modified mandibulate," and they form a short tube that is ideal for sucking nectar out of short-corolla flowers. The nectar is stored in the "honey stomach" and is transported back to the hive where it is regurgitated and fed to sister bees. 

Things you don’t expect to see on a college campus

The Austin College campus is on about 85 acres on Grand Avenue, east of downtown Sherman, TX. It is surrounded by neighborhoods, but there is some open land as well, which is owned by the college and will eventually be used to expand the campus. There are plenty of things you do expect to see on a college campus. Students, faculty, and staff. Lots of fox squirrels, at least on our campus. Pleasant and educational landscaping, architecturally interesting buildings, fountains, benches, bicycles. But occasionally you see things that seem out of place.

 

Like skunks.

 

The common local skunk in north Texas is the striped skunk (Mephitis mephitis), called that for obvious reasons. These are generally crepuscular creatures, so you occasionally see them out in the morning or evening. The obvious thing about skunks is their predator-defense mechanism – they spray a noxious, smelly chemical from a pair of glands near the anus. Most mammals have a pair of anal glands that produce odors, but skunks take it to the extreme.

 Another animal that can be seen occasionally on the Austin College campus is Cooper’s hawk. This is a relatively small bird of prey whose preferred prey is other birds. I have seen them flying through the trees on campus, and when a Cooper’s hawk is on the prowl, the smaller birds go crazy giving alarm calls and ducking for cover. If you see a flash of grey feathers followed by a puff of blue ones floating to the ground, that usually means a Cooper’s hawk has nailed a Blue Jay.

Tarantulas are pretty common at certain times of the year.

 

Lined snakes are too. Their preferred habitat is lawns and short grass areas, so the campus provides plenty of habitat for them.

 

A pretty rare find on our campus is a black rat snake (Pantherophis obsoletus). This one was on the ground in a small grove of live oaks between Baker Hall and Dean Hall. It was an about 2 meter long full grown adult female.

 

The day I took this photo, I was walking toward the building where my office was. There were employees of a tree trimming service on campus. They were throwing a metal pipe at the ground, picking it up, throwing is again. I thought, I know what they are doing. Sure enough, they were trying to kill the snake with the pipe. Fortunately, their aim was bad, and the snake was uninjured. It was, however, pretty riled up. I thought, this is a teachable moment, so I approached the snake, set my briefcase down in front of it, and reached around and grabbed it (I have caught a lot of snakes in my time as a field biologist). The tree service guys screamed “NO! It’s a water moccasin!” It will bite you!” I replied, no, it is a black rat snake, perfectly harmless and in fact beneficial because they eat rodents. I took the snake into my building, let it calm down some, then took it a safe distance from campus and turned it loose.