Monday, September 8, 2008

Cronquist and the Dayflower

On my recent botanical foray to the sand knolls and wetlands of Indiana'a Jasper-Pulaski Wildlife Area, I encountered a plant that instantly brought back a flood of memories. Even though I had never seen this species before, it had a profound influence on me, and led to a most memorable encounter. Indeed, an experience that helped shape my views on encouraging others in their pursuit of natural history.

A charmer, to be sure, is Erect Dayflower, Commelina erecta, seen here in some of the best sand prairie in the midwestern United States. I was thrilled to finally see this plant in the wild, and catch it at the peak of bloom to boot. All of the dayflowers are lookers, but this is perhaps the showiest.
Dayflowers are monocots closely related to spiderworts, and rushes for that matter. The botanically inquisitive will not be overwhelmed with species to learn: we have but two native species in these parts. Two others are widely established weeds originally native to Asia; Asiatic Dayflower, Commelina communis, is the best known and most frequently encountered.

Erect Dayflower is as native as they come, and often occurs in superbly diverse prairies, as at Jasper-Pulaski. The genus is named for the Dutch botanist Jan Commelin. As with some other dayflowers, two of the petals are extraordinarily bold, showy, and blue; the third is depauperate and whitish, hardly matching the glory of its two siblings. This weak petal is the lower one.

On to the story, now that our plant has set the stage.

In 1991, the above was released. Manual of Vascular Plants of Northeastern United States and Adjacent Canada was burdened with a lengthy and cumbersome moniker, but this was the bible of vegetation botanists had been eagerly awaiting. You might say it was the counterpart to birding's big Sibley guide, and when it emerged we snapped it up. Few were disappointed. Written by the brilliant Arthur Cronquist, the manual was innovative in the extreme. Not for the casual, it has no photos or sketches, just pure dichotomous keys and individual descriptions of plants. But we finally had a thorough, accurate and up to date guide to ALL the plants in our region.

So, like many others, I pored through the manual with a keen eye, looking for new information and lore. And before long, I came to page 656. And Commelina erecta. And Cronquist's range description: " Pa., O., Mi..." What!? Ohio! We had no record of this species in the state, and discovering it here would be akin to finding a breeding Swainson's Warbler. Surely Arthur Cronquist knew something the rest of us didn't. After all, he worked out of the fabled New York Botanical Garden, and had one of North America's most comprehensive collections of plants at his fingertips in their herbarium. Not to mention his vast experience and exploration. Maybe Arthur had found the plant in an Ohio pass-through and neglected to let on to the rest of us.

Action was required to ferret out the status of this dayflower in Ohio. So on December 27, 1991, I tapped out the above letter. It is addressed to Patricia Holmgren, who was the Director of the New York Botanical Garden's herbarium. I had previous contact with her in the course of sending along numerous plant collections from Ohio to be deposited in their esteemed institution, and Ms. Holmgren had always been very gracious. Thus, I thought she might help solve the dayflower mystery, being in the same facility as ARTHUR CRONQUIST, who I didn't dare contact.

In case you can't make it out, my letter says: "

Dear Pat:

I sincerely appreciate the help you have given me in the past, and hope you can assist with another request, this time concerning Commelina erecta L. Cronquist (1991) lists Ohio as included in the range of this species, yet I know of no specimen in Ohio herbaria and the plant is unmentioned in works dealing with Ohio flora. Perhaps there is a sheet in the NYBG herbarium, and if so, could you send me a copy of the specimen and label?

Thanks very much for your time and consideration.


James S. McCormac"

Lo and behold, a few weeks later I received a reply letter, dated January 7, 2002. And who should the author be, but Art Cronquist himself! If you click on the letters above, they should enlarge to make for easier reading. In case you can't below is Cronquist's letter:

"Dear Dr. McCormac (his error; no Dr. here!)

Dr. Holmgren has passed on to me your recent inquiry about the attribution of Commelina erecta to Ohio in the recent G. & C. Manual (Gleason & Cronquist). I remember, from the days when I was going to Sunday school regularly, being warned, "Be sure your sin will be found out". The attribution of C. erecta to Ohio goes back to Gleason's version of the Britton & Brown flora, published in 1952. It is not unreasonable on its face, and I did not check it out for the two editions of the manual. I don't now find anything in the herbarium to validate the record.

It might be well to check with Dr. Robert Faden, of the Smithsonian Institution, about the distribution of this species. He is a specialist in Commelinaceae, and he annotated our material of Commelina several years ago. He may have some records that neither one of us knows about.

Sincerely yours,

Arthur Cronquist

Senior Scientist"

Needless to say, this 30 year old eager botanist was ecstatic to have received a letter from the MAN himself, and I could hardly believe he had written me personally over what might be considered such a trite matter. But Cronquist knew the field botanist mindset, being one himself. He knew that discovery of a new native plant to a state was a big deal, and thus took the time to set the record straight. What's more, he did it with humor and style. I especially liked the part of his letter where he states "I remember, from the days when I was going to Sunday School regularly, being warned 'Be sure your sins will be found out'".

Arthur John Cronquist, 1919 - 1992. Cronquist passed away on March 22, 1992, two and a half months after he wrote the dayflower letter to me. He went out doing what he loved best - studying plants. While examining specimens of Mentzelia at Brigham Young University in Utah, he suddenly collapsed, dead of massive heart failure at the age of 73.

Cronquist was an extraordinary intellectual, and an innovator on many levels. He is probably most famous for his revision of the taxonomic system of plants, eventually creating what came to be known as the Cronquist System, a scheme that is widely accepted and in use today. The fact that he would take the time to answer a query from a complete unknown meant a great deal to me, and taught me a big lesson about encouraging others. I've never forgotten Arthur Cronquist's taking the time to pen me that letter, and it was the first thing I thought of when I realized I was looking at a beautiful specimen of Commelina erecta last Friday.

To me, Cronquist lives on throught that gorgeous species of dayflower.


Janet Creamer said...

Awesome post and a great shot of a gorgeous flower. Take it from the "little pup" who got to hang for a day with the "big dogs" and botanize. Encouraging others to pursue natural history is one of your strengths. Keep it up.


KatDoc said...

Beautiful post, both the second photo of the dayflower and your tribute to a generous and obviously revered man.


Anonymous said...

Wow, what a neat tale and a nice tribute to this good man and scientist, pretty cool.
- ben warner

John said...

Fantastic story!