ID requested for Trillium cf. chloropetalum

aaron floden
Tue, 02 Apr 2013 17:40:15 PDT
If anyone is willing to send material enough for a voucher and DNA of the western species it would be much appreciated. My advisor and I are continuing work on Trillium Phyllantherum and only have T. albidum, of the western spp.,  currently included in our phylogeny. If needed I could arrange payment of shipping costs (we only need a stem, no rhizome).

 After the comments a couple weeks ago I looked at the new Jepson and saw that they lumped kurabayashii and angustipetalum. It may be correct, but given the likely long isolation of the two I would think that Freeman's original circumscription was more accurate. 

 E Tennessee

--- On Wed, 4/3/13, Mary Sue Ittner <> wrote:

From: Mary Sue Ittner <>
Subject: Re: [pbs] ID requested for Trillium cf. chloropetalum
To: "Pacific Bulb Society" <>
Date: Wednesday, April 3, 2013, 7:03 AM

After Gastil's post I found this:…
So it seems that they think they have T. chloropetalum.

A couple of years ago a friend and I tried to key out some Trillium 
we thought were T. chloropetalum after adding them to the wiki under 
that name and getting an email saying we were wrong. We used three 
keys and found nothing matched perfectly, but finally decided that 
what we were seeing was probably Trillium albidum. There was a lot of 
variation in the populations and some of the flowers were pink.

I'll include what I wrote afterwards showing how challenging it is 
sometimes to come up with a correct identification from a photo and 
even when you have the plant in front of you. Often photos don't show 
the important identifying features.

"Flora of the Sonoma County key:
Flowers with portion of the filament joining the 2 cells of an anther 
greenish; filament usually green, sometimes purple, anther dehiscence 
lateral; tepals white (rarely purple basally) to pink -- T. albidum 
Flowers with stamens and anthers purple throughout; anther dehiscence 
turned inward; tepals varying from purple to yellow or white -- T.

Flowers in the first one we looked at from one population had purple 
filaments and the  direction of the anthers was a bit uncertain. They 
didn't really look lateral, but weren't entirely  turned inward 
either. Flowers in a second population several people have been sure 
was T. chloropetalum also had purple filaments. These anthers turned 
inward. The anthers were not purple however in either population. 
They were greenish.

Plants of the SF Bay region key:
Petals whitish, yellowish, or dark purple; fruiting portion of pistil 
purplish; top of the filaments between the anther sacs purplish -- 
Trillium chloropetalum

Petals white to pink; fruiting portion of pistil usually green, but 
sometimes slightly tinged with purple, tip of filaments, between the 
anther sacs, green -- Trilium albidum In both populations the 
fruiting portion of the pistil was purplish and the top of the filaments purple

Jepson (this was before the new version came out):
Ovary and tissue between anther sacs greenish; petals white to pink 
(base sometimes purplish) - T. albidum Ovary and tissue between 
anther sacs purple; petals yellow to purple, sometimes white - T. 
chloropetalum The tissue between anthers sacs was greenish, not 
purple. However, the ovaries of one of the populations were green and 
the ovaries of the other population were purple, except for four 
plants with green ovaries. This was a very large population of plants 
and only the four plants had green ovaries, but it made us wonder if 
the color of the ovary was really a defining characteristic.

The descriptions in Jepson says that sometimes T. albidum can have 
purplish ovaries."

We consulted a friend who had recently worked on this same issue in 
another part of Sonoma county and she said she thought the color of 
the anther sacs was the crucial character. After we figured out what 
the anther sacs were, we found there were green so concluded that 
they were both T. albidum even though the one population had always 
been identified at T. chloropetalum. So the identification of the 
flowers got changed on the wiki. I never got around to adding my 
photos that showed some of this more clearly, but I should do so one 
of these days.

However, I shared this with another plant expert in our area and he 
shared a quote from someone from the Jepson Herbarium that I really 
like: "just because something keys to something, it doesn't mean it 
is that something!"

Mary Sue

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