Orobanche multiflora

Orobanche multiflora
Many-flower Broomrape
Percha Box, East of Hillsboro, New Mexico, USA
August 2, 2015

When we originally published this entry (June 2018) we identified this plant as Orobanche ludoviciana subsp. multiflora (Louisiana [Many-flower] Broomrape.  The most current version of Flora of North America (2020) identifies this plant as Orobanche multiflora.  We have retained our original entry (below) with annotations (shown in Copperplate font in red) to bring it up to date.  We believe this treatment is useful in clarifiying the taxonomic determinations of this species over time.  Our sincere thanks to Dr. Turner Collins for bringing the current taxonomic determination to our attention and for his work on the Flora of North America.


Sometimes a chance encounter can take you aback and cause a moment of reflection.  That happened to me on August 2 of this year (2015) as I walked near the Percha Box, east of Hillsboro.  I had been walking in the stream bed, jumping across the rivulets of water when I could and wading across when I could not.  It had been raining all afternoon in the Black Range to the west and the falling water was getting closer and I was afraid that the running water that would go with it might be coursing down the creek at this very moment.  Up on the bank I went, walking along a cow path and there in the sandy soil, on a bank that could wash away in any high water event, was a Many-flower Broomrape, Orobanche ludoviciana subsp. multiflora.  (See revision of taxonomic determination above.)  Just as I started to take photographs of the Broomrape and its sibling nearby, the rain came, my hat came off to cover the camera and hat and camera went under my shirt for added protection.  Then I trudged off up the stream, bent over to provide a bit more protection for the electronics, water streaming off the end of my nose.

As I walked along the stream, I mulled the life of a parasite - I’m not talking politics here.  In many ways it is a difficult way to exist, the parameters of existence are so strongly defined by another being.  When I am wet and slogging through sand and water I am prone to think about such things, I mean, no one else will...  Well, in this case Artemisia carruthii (Carruth’s Sagewort or Sagebrush) which is a primary host of this broomrape, seems to be doing okay.

USDA range map for Orobanche ludoviciana Nutt. ssp. multiflora (Nutt) T. S. Collins ex H.L. White & W. C. Holmes 5:2024)

The common name of this species is Louisiana Broomrape (it is also the name of the nominate subspecies), as opposed to Many-flower Broomrape which is the name of the subject subspecies - there are only two subspecies.  Its range extends south into Mexico.  (As noted above, the current treatment for this species is Orobanche multiflora and there are no recognized subspecies - but some authorities have described [up to] four varieties.  It would appear that the common name, Many-flower Broomrape, is appropriate for the plant found here.)

The range map to the right (top) is from the USDA Natural Resources Conservation Service and shows the range of the subject subspecies.  O. l. multiflora was initially described by Thomas Nuttall, as Myzorrhiza multiflora, it now has several scientific synonyms.  Both subspecies are found in New Mexico so it is not possible to parse the subspecies range from the first map.  (The top range map [as of May 2024], of O. l. multiflora, shows the plant occurring in Soccoro County but not Sierra County.  The bottom range map (5/24), of O. l. ludoviciana, indicates that this subspecies is found, in new mexico, only in the far north. As of May 2024 the U.S.D.A. site, the Vascular Plants of the Gila Site, and other sites {like the Lady Bird Johnson Wildflower Center] do not split O. ludoviciana into two species.)

Some people have roasted the roots and young stems of this species to eat and it has been prepared and used as a dressing for wounds and a treatment of ulcerated sores.  In this case, especially, care should be taken before eating or using this plant.  Parasitic plants absorb a variety of substances from their host (in this case, members of the Aster family in general and the genus Artemisia specifically), creating a substantial uncertainty about toxicity (among other things).

The specimen sheet shown below has a specimen collected in Sonora as part of the survey for the International Boundary Commission of the United States and Mexico, on August 28, 1893.  The specimen was collected by E. C. Merton in Guadalupe Cañon (a very famous birding area).  (Note that the current U.S.D.A county level range map does not show this species in the very southeastern corner of Arizona.)  In his 1907 publication “Mammals of the Mexican Boundary of the United States”, Bulletin 56 of the Smithsonian Institution, Edgar Alexander Mearns described Ernest C. Merton’s role as “acting hospital steward. U. S. Army. Collected plants between the San Pedro River and Dog Spring (Monuments Nos. 98 to 55) from August 1 to September 23, 1893.” (p. 6 and again at p. 130)  Merton is referenced in other parts of the report as well:

“On September 27, accompanied by Hospital Steward Ernest C. Merton, I rode to the forks of Cajon Bonito Creek and camped there for the night, returning to Lang’s Ranch September 28, after exploring a greater extent of the upper portion of the Cajon Bonito Valley than had hitherto been done.  At this period the dreaded Apache Kid’s band of Indians was present in the neighborhood.  On September 24 by men obtained the skull of a puma which had just been skinned by these Indians, the puma’s body being still warm when the soldier’s found it.  Steward Merton came upon the Indian camp in a canyon on Cajon Bonito Creek on the night of September 27, but fortunately avoided observation and succeeded in reaching my camp during the night, although a severe storm was in progress and the streams swollen.” (pp. 15 - 16)

“No more were seen by me until October 3, 1893, when Hospital Steward E. C. Merton brought me another” (Colorado River Toad, Incilius alvarius, at that time described as Bufo alvarius) “that he had just caught at a spring situated between Monument No. 73 and Cajon Bonito Creek, in Sonora Mexico.” (p. 114)

To his credit, Mearns, who is a “big name” in the natural history of this region seemingly was more than willing to give credit where credit was due.  Note, for instance, that Mearns’ collection sheet has Mearns name crossed out and Merton inserted.


There is little else known about Merton (that I have found).  But for the willingness of Mearns to recognize the efforts of others he would be just another lost name in history.

(In January 2024, Dr. Turner Collins, brought the current Taxonomic determin-ation in Flora of North America to our attention.  In 1972 he had made the entry to the right on the specimen sheet shown below.  In January 2024, he noted “My opinion changed as I studied the genus, and my current treatment of O. ludoviciana and O. multiflora is in vol. 17 of flora of north america.  they are definitely different species and can be distinguished easily by anther pubescence and corolla size.  There is also DNA evidence to support the distinction . . . The type specimen for Orobanche multiflora is lost.  I have searched all herbaria in the U.S. where such a type might exist, and none has been found.  Kew has been searched by several different individuals on my behalf, and none was found.  Of interest here, is that Nuttall’s holotype for Orobanche ludoviciana is at the Philadelphia Academy . . . When Holmes & White published O. ludoviciana susbsp. (multiflora) as a new combination, they designated a lectotype from south texas   . . . [but} Gamble collected the type speciment that Nuttall used in New Mexico somehwere near Santa Fe.”  [Personal Correspondence Collins/Barnes january 24, 2024])


IMG_3240 - Version 2



droppedImage_1


© Robert Barnes 2018-2024