Digitalis 'non-stewartii'

[Karaba]

I've asked and received (lots of) seeds of Digitalis stewartii from SRGC seed exchange. Looking for information about its origin, I've found very little information and asked myself if it is a "real species".
The only information that I have found on the web is that it's the tallest foxglove, close to D. ferruginea and D. laevigata, maybe an hybrid and it may come from Turkey.
But, D. stewartii is not listed in the Plant List, it is not listed in scientific papers about phylogeny of Digitalis : a PDF and a summary of an other paper
It looks like it is a recent introduction in the garden.
If anybody has information about this species : origin of the name, description, wild origin (if any), differences with other close species...

[johnstephen29]

Hi Yvain are you able to access the Google search engine where you are? I typed in digitalis stewartii and lots of results came up, I'm sure you will find all the information you asked about.

[Gabriela]

I don't think there is such thing as D. stewartii. See a link below, you may use the google translator
http://www.janvanduinen.nl/ferruginea.html

It must have been a cultivar of D.ferruginea and someone listed it once with the cv. name instead of the specific epithet (like it too often happens unfortunately) and for a plant that sets lots of seeds it was enough...most people are kind and share their seeds....
(like Digitalis ferruginea var. gigantea offered as Digitalis 'Gigantea' and so on) It's getting from bad to worse when it comes to the names. I may be wrong of course.

Another unfortunate trend is to write the common name of a species (usual from a more 'exotic language')  as a cultivar, so to make the species look more appealing to the public. Crazy, eh?

[Karaba]

I think you're right, Gabriela.  (see also http://www.hessenhof.nl/al/d144.html)

The fact is that D. stewartii is now sell by many nurseries and can even be found in botanical garden like Uppsala (http://green-24.de/forum/juliraetsel-2013-t94749-705.html) or Denver (http://navigate.botanicgardens.org/weboi/oecgi2.exe/INET_ECM_DispPl?NAMENUM=39452&DETAIL=1). It's even in the australian list of permitted plant for seed import (https://bicon.agriculture.gov.au/BiconWeb4.0/ViewElement/Element/CaseScientificNames?caseElementPk=299692).

I've received today a recent paper "Phylogeny of Anatolian (Turkey) species in the Digitalis sect. Globiflorae (Plantaginaceae)" from Eker et al., 2016, Phytotaxa 244 which is very interesting as there is a key and some illustrations of 6 of the turkish Digitalis sect. Globiflorae : D. cariensis, D. lamarckii, D. lanata ssp. lanata, D. lanata ssp. trojana (new statu for D. trojana), D. ferruginea and D. ferruginea ssp. schischkinii (no mention of D. stewartii...). Pictures of D. stewartii found on the web are very similar to D. ferruginea ssp. schischkinii. This paper also aid me to identify one of my fowglove. My "D. lanata" (bought with this name) is D. ferruginea and probably ssp schischkinii. Do I rename it as D. stewartii 

[Gabriela]

You could give it a try for a Digitalis yvainii

Things are clear if it's not in the recent Phytotaxa (I also chequed Flora Europaea). I once saw a D. ferruginea ssp. schischkinii - I liked it, very distinct, one can tell from the distance is a ferruginea but somehow different.
You should grow few seedlings, make sure what they are with the new key (no sharing to seedex please  .

[Tristan_He]

How interesting. I always thought that the pictures of "D. stewartii" I saw in seed catalogues looked remarkably like D. ferruginea. Looks like there was a good reason!

[Jupiter]

I have a passing interest in species digitalis, but haven't grown (so-called) stewartii.

It's not listed in the Kew Gardens Plant List - http://www.theplantlist.org/tpl1.1/search?q=Digitalis   I reckon that's the final word. D. stewartii is non-existent. It'd be nice to know definitively what it really is...

[P. Kohn]

I have just planted a very nice looking plant under this name. Both Plantworld and Chilyern offer seeds under this name so it isn't surprising that several nurseries are perpetuating the name. The Plant Finder records nurseries selling under this name with an asterisk denoting an unvalidated name.

[meanie]

Have any of you had any luck blooming this? It would be interesting to see the results.

[P. Kohn]

Ours flowered very well but being very tall and thin wasnt very photogenic. If one googles imges of D. stewartii, some of the images are indistinguishable from ferruginea but others with a more continuous column of flowers look distinctive and ours was in this catregory.

[Gabriela]

Ours flowered very well but being very tall and thin wasnt very photogenic. If one googles imges of D. stewartii, some of the images are indistinguishable from ferruginea but others with a more continuous column of flowers look distinctive and ours was in this catregory.

This is a good description for D. ferruginea ssp. schischkinii.

[sokol]

I gave the seed to the seed exchange last year.

D. stewartii has smaller flowers than D. ferruginea not reddish brown but yellowish brown. It is a much taller plant reaching 2m in the garden. It is also long-lived compared to D. ferruginea.

I have found it in the wild in the Dilek Peninsula National Park in 1995 and it flowers 1996 or 1997 in my garden. I have another clone of a nursery since 25 years that is very similar but lower. I attach pictures of both. Maybe they can help you. I do not remember who told me the name or where I have found it.

If Kew doesn't list it does it mean that there is no original description or just that Kew thinks it is a synonym?

[Karaba]

I gave the seed to the seed exchange last year.

D. stewartii has smaller flowers than D. ferruginea not reddish brown but yellowish brown. It is a much taller plant reaching 2m in the garden. It is also long-lived compared to D. ferruginea.

I have found it in the wild in the Dilek Peninsula National Park in 1995 and it flowers 1996 or 1997 in my garden. I have another clone of a nursery since 25 years that is very similar but lower. I attach pictures of both. Maybe they can help you. I do not remember who told me the name or where I have found it.

If Kew doesn't list it does it mean that there is no original description or just that Kew thinks it is a synonym?

I found no description and even no author attached to the name. It is not listed in the Plant list nor in scientific papers about phylogeny of foxgloves and turkish foxgloves. So, I 'm now quite sure that there is no Digitalis stewartii (and it's even not a synonym since there is no description) and that the true name of this foxglove should be Digitalis ferruginea. Indeed, I looked again at Eker's paper and there is a map of turkish foxgloves : at Dilek Peninsula, there is only D. ferruginea ssp. ferruginea and D. cariensis.... D. f. schishkinii is distributed in north-east Anatolia. So, yours D. stewartii should be D. ferruginea ferruginea. Other might be D. f. schischkinii or even hybrid with D. laevigata ?

[ChrisB]

This is slightly off topic, but I was told by a botanist that digitalis comes true from seed and that they don't mix with other species.

[meanie]

Interesting to see the confusion about this. the reason that I asked was that I saw what was labeled as Digitalis stewartii at Oxfords Botanic gardens back in the summer. As I recall it was not massively tall.


Apart from the previously mentioned narrower flower heads it wasn't that different from Digitalis ferruginea. Here is a clump of D.ferruginea that I grew from bought seed. They were quite variable and I've embedded a large size of the photo so that it is easier to see the additional inflorescences on some plants...............