Bunny-ears Senna

The problem with common names for plants and animals is there is no standardization or convention. Common names frequently are descriptive of some characteristic or quality of the creature. Essentially, they are nicknames that can very from one community to another.

Early this week I led a hike for 4th grade students along the Oak Loop Trail at Hardberger Park. While discussing the characteristics of Velvet-leaf Mallow with the class, the topic of how plants get their common names entered the discussion. The source of the common name for this plant is quite obvious.

The next wildflower we saw along the trail was Lindheimer's Senna, so I explained that sometimes the common name of a plant honors the person who first described it. In the case of this senna, it was first described by Ferdinand Jacob Lindheimer, one of the pioneer naturalists in Texas.

Then we came to a cluster of Senna roemeriana.* I showed the group of 4th graders one of the leaves from this plant and asked them what they looked like, hoping to get a response something like, "It has two leaves on a stem." It is a single compound leaf with a pair of leaflets.

One of the students immediately replied, "It looks like bunny ears." I had to agree. So now in my book, the Senna roemeriana will always be Bunny-ears Senna, even if everyone else still wants to call it Twinleaf Senna:

This set of photographs was taken along the Oak Loop Trail in Hardberger Park on Monday, October 21, 2013.

* Correction, Saturday, October 26, 2013: In the original post, I misidentified this plant as Senna bauhinioides. This brings up another problem with common names. When I was preparing this post for publication, I did a search on wildflowers.org's native plant database using the common name "twinleaf senna" The only result the search gave me was for S. Bauhinioides.

This morning, my botanist friend and primary fact checker pointed out this is actually S. roemeriana. The only common names the native plant database lists for this species are "twoleaf or two leaved senna."

If I had verified the identification by checking my field guide or by doing a search for "Senna" in the database, I would have realized the problem with the common name for this plant and found the correct identification.