Trillium taxonomy 2014

[Robert]

All this discussion has certainly inspired me to do more field work, especially with our native Trilliums. Plants that are different always seem to show-up.  ...and in nature, everything is in constant change. I wish that I had field notes from my travels 45 years ago. I'll keep everyone posted on what I find. 

[Ed Alverson]

Do you have any basic book references? I prefer college text books, no internet please. Through Worldcat our library can get almost any book.

Robert,

A book that might be of interest to you, which is reviewed in the most recent issue of Castanea, is "Tree Thinking: An Introduction to Phylogenetic Biology", by David A. Baum and Stacey D. Smith. It was published in 2012 by Roberts and Company Publishers. The review is generally positive and it sounds like it is designed to be an introductory college level textbook on the topic.

[Afloden]

Robert and others,
 
 I agree that hybridization may be more of a problem in the western NA Trillium. One problem I see is that T. chloropetalum seems so variable, but we do not have the necessary nuclear markers yet to test for parentage. Also chloro- is green and most of what people call chloropetalum has those reddish petals. The type specimen is clearly a greenish flowered plant. Maybe the type was from a hybrid zone?

 In our lab we are happily accepting material of any sessile Trillium with documented provenance! We just got T. petiolatum this week and will have far more sequence data soon compared to previous phylogenies that have utilized only matK and rbcL, neither of which provide any species level data in Trillium. We do have three whole chloroplasts for Trillium and may end up with a lot more given time and money. Our first phylogeny was published last year and the description of a new species, T. tennesseense, which is pictured in my previous "quiz" post (on the far right). It is morphologically similar to T. oostingii (the two left plants), but also easily separated from it by morphology, DNA, and fragrance (as well as distribution). We are preparing to describe the Ruby Falls Trillium and yet another species from Georgia (USA). That first phylogeny only had T. albidum from the West included in it. Our current phylogeny that we are preparing to publish has far more sampling of the western NA species; 3 albidum, 1 chloropetalum, 1 parviflorum, 1 angustipetalum, and 1 kurabayashii. We are always happy to accept more. This spring we have added over a dozen new populations of southeastern sessile species in an attempt to sort out the lancifolium complex and also many more samples of cuneatum.

 

 

[Robert]

Aaron,

It seems that more field work with the Western Trilliums could be a good. How our thinking about them has change over the years. Our ideas in science can and do change all the time as new information becomes available. Take a look at the California Floras by (Willis) Jepson, 1960 or (Philip) Munz, 1959.

If I find any Trillium colonies that seem like they could be significant I will post photo(s) on the forum.

Also, thanks for your input. I may never be able to get up to speed on some of the science, after all I'm a gardener, but all this does prompt me to take a closer look at the whole situation and sharpens my skills in the field.

And how will the DNA testing be used to determine Subspecies and/or variety status? I hope that something can be worked out that is workable for us gardeners too. As a general question, in addition,  Is anybody in the general horticultural world consulted in these decisions?

[Rick R.]

Thanks for answering your quiz question, Aaron.  I am sure we have all been wondering.....
 
All I could say is that I know enough not to know!