Monday, August 13, 2012

Button Weed

Also known as "Poor Joe," this little plant in the coffee family (Rubiaceae) can be quite common in dry sandy sites that are open and disturbed. I first noticed it in the mid- 1980's while exploring with Ken Klick and Sandy O'Brien. None of us recognized it, so Ken and Sandy ran it through Swink and Wilhelm's keys to the families and genera. 
They worked together and did this out loud, showing a remarkable understanding of the language of botany and its myriad descriptive terms. They arrived at Diodia teres var. setifera without ever looking at a picture! It was an excellent lesson in the value of botanical keys, the most accurate way to identify an unknown plant. Thanks Ken and Sandy for providing me with the impetus to learn the language of botany all those years ago! Photographed near Knox, Indiana.

4 comments:

Scott Namestnik said...

Any idea where the name "Poor Joe" comes from? Isn't that also a common name for Plantago aristata?

Keith Board said...

That name was used in print somewhere years ago but don't remember where. I just discovered that the USDA Plants database calls it "poorjoe" (one word). It's probably a name that is used for a variety of plants that grow in harsh, dry conditions.

Lisa at Greenbow said...

I am glad you posted this. I was just pulling a lot of this from the fence line and was wondering what in the world it was. Now I know.

Nick said...

My copy of E.R. Spencer's book "All About Weeds" provides an answer. Poor Joe (Diodia teres) "grows in the poorest of cultivated ground" "The weed is insignificant and scarce in rich soil areas, but seems to rejoice and flourish in difficult situations"