Gunnera but which? Manicata or tinctoria; was stumper: seen around town now

Re: seen around town now

maf, could we get a photo of the back of the M. tinctoria leaf where it meets the stem? I really don't think I've shown any webbing, but maybe it would be helpful to compare the ones here to the one you know is tinctoria?

 

Re: seen around town now

I am not sure if the webbing and scales the articles are referring to is where the leaf stem meets the rhizome, rather than where the leaf meets the stem, but it is not 100% clear from their wording, they just state the base of the leaf:

Either way, I have never used this method to tell them apart, the first I heard of it was last week.

Regarding the difference in the flower spikes, the side branches (for want of a better word) in G. manicata are relatively thin and long and the central stem is clearly visible, wheras in G. tinctoria they are shorter and fatter and it is difficult to see the central stem. (In newly emerged inflorescences the difference is less apparent.) The close up pictures of inflorescences in post #25 are all clearly G. manicata.

I was googling for some pictures and happened upon an old thread from UBCBG that you might find helpful, don't know if you saw it already:
http://www.botanicalgarden.ubc.ca/forums/showthread.php?t=41153
The guy is probably better at explaining the differences than I am.

I am 100% sure that most of the pictures in post #25 are G.manicata, but not 100% on the last two, need a better picture of a fully expanded inflorescence (Edit: but the plants look large enough to be manicata).

Photo as requested in post #26:

 

Re: seen around town now

Yeah, I was just wondering if it was possible........

I have never heard that the two species can hybridise, but then again I have never heard that they cannot. Maybe someone knows for sure?

 

Re: seen around town now

Thanks, maf. That leaf in your photos doesn't look different to me to the others. Do you see anything different?

Here's another photo of the original planting. The stem is not visible on the inflorescence at the front, but it's visible on the one in the background. That's what I mean about these characteristics. Does amount of sun make a difference for that?

This is reminding me of high school biology class where nothing ever looked like it was supposed to (and I just about failed when I was still reporting what I saw instead of what the book said I was supposed to see).

 

Re: seen around town now

Oh that part of the base of the leaves? I'll bet this is it! This is one of the Stanley Park plants.


Is this the same stuff? This is the original plant posted.


Is it the same stuff in the POTD posting from UBCBG?

It's the stuff at the base of the leaf stalks on the Gunnera petaloidea photo on nature.berkeley.edu's Karl's Hawaiian plant photos page that's the reason I ruled out G. petaloidea, which is the Hawaiian 'ape'ape. Same kind of stuff, but it looks different, right?

It's certainly not visible at the base of all the leaf stalks.

 

Re: seen around town now

The inflorescence in post#29 also looks like Gunnera manicata. The "side branches" are much shorter and stubbier in G. tinctoria. I liked the sweetcorn analogy for tinctoria in that other thread.

When you see a Gunnera inflorescence try asking yourself what does it most resemble, a bottle brush or a cob of sweetcorn? That might work, but is admittedly not very scientific.



No flowers on our G. tinctoria this year, as nearly all the overwintering buds were killed and it is only growing back from a couple of places under the rhizome. If it sends out any flowers later in the summer (doubtful) I will post pics.

 

Re: seen around town now

Nope, it doesn't work for me, but maybe if it works for you, you can tell us which this UBC one is. :) I swear this looks exactly in between a bottle brush and a corncob. This is the plant that was renamed G. tinctoria on the POTD but the accession signs (and the database) still say G. manicata.

We've got a lot of red stems here and also red veining on one leaf.

This plant might be a bit behind the others in development, so it might not be fair to judge the inflorescences yet.

Thanks to maf's hint, I've got the scales now, which are what are shown in posting #30, and all that stuff on the rhizomes. According to that RNZIH page referenced before, on both species:

I should have read that more carefully. So the question is, are we seeing the "prominent development of membranous "webbing" between the main lobes of the scale whereas in G. tinctoria this is not well developed and so the lobes are often almost free to the main rachis of the scale" here and in posting #30?

 

Re: seen around town now

I'm getting a little confused as to which plant is which, I thought post#29 was the original plant, but that does not look the same as the one in post#32. If the inflorescence in #32 has reached its maximum width then it must be Gunnera tinctoria. Also the way the leaves look in the group shot, the way they held at an angle and many are cupped, reminds me of G. tinctoria.

Also, is the last picture in post #32 from the same plant as the second last picture?

 

Re: seen around town now

Sorry. The plant in posting #32 is new here, except that I'd mentioned the POTD posting on it in posting #9, and that Douglas Justice had ID'd it as G. tinctoria, which is why I was wondering if we'd think it looked different from the others. I don't know yet if the inflorescences will get larger, though Douglas's description of G. tinctoria mentions inflorescence branches (what they seem to be called) "stiffer, to 12 cm on G. tinctoria". Surely, that's what he thought applied to that individual when he ID'd it as that. All photos in post #32 are from the UBC plant.

Posting #29 is the original plant.

I hadn't meant to make it a trick question, but it seems you've confirmed the G. tinctoria ID for UBCBG's plant. Now I just have to figure out what about the scales looks different.

 

Re: seen around town now

Ah, ok, I definitely agree #32 is Gunnera tinctoria. For some reason I was thinking it was supposed to be the same planting as #29 which is G. manicata, hence my confusion.

I will look out for the webbing when I view Gunneras in the future, but it is not a characteristic I have paid much attention to in the past.

Can you see the difference in the proportions of the inflorescences now you have observed both?

I have never tried to analyse or explain the differences between them before, it is more difficult than just being able to tell the difference, which seems to come more naturally for me.

 

Re: seen around town now

Right, but there are two problems with that:
1 - it doesn't help me for the next ones I find, unless you'll be on call to identify them all for me; and
2 - Douglas, whose ID was reported by Egan in an earlier posting, maybe thinks it comes naturally to him too, but you and he had different IDs on one of them.

This photo by Eric Hunt of G. tinctoria in Strybing Arboretum demonstrates the cupped rather than flat shape of the leaves that's been mentioned. (From Wikipedia, Creative Commons license)


Here's a photo from VanDusen of the plant Egan thinks is G. tinctoria on the right, and the presumably G. manicata on the left.


Is this webbing on this not-labelled VanDusen G. manicata? Inflorescence branch was 13cm.


This is webbing, right? Different VanDusen plant.


I'm having a problem with this plant, as the inflorescence branches are around 18cm. That's quite a bit larger than what they're supposed to be. Do I really have to consider some other genus, as Michael suggested? Maybe only these two large ones have been imported around here?


Here's the original Granville Island plant again. It also has some very long inflorescence branches (21cm). And webbing?

I'm calling it G. manicata until someone says it's not either of the two examined here.

 

Re: seen around town now

I don't think 18-21cm inflorescence branches is a problem for G. manicata, the inflorescence can be as wide as 40cm, possibly even more in a well grown older specimen.

AFAIK, G. manicata and G. tinctoria are the only large leafed gunnera species hardy in a temperate UK or BC type climate, I wouldn't consider any other species unless new information comes to light.

Here is a thread I found at Growing on the Edge forum, which has some decent comparison shots of both species, taken at the same time in the same garden:
http://www.growingontheedge.net/viewtopic.php?f=2&t=3203
And one with some discussion on this topic:
http://www.growingontheedge.net/viewtopic.php?p=10466

At least one of the posters mentions the texture of the leaves, which is more leathery/crinkled/crumpled in G. tinctoria, another good visual clue.

 

Re: seen around town now

Thanks, maf. Back to my high school biology class experiences again. At your first link, the G. manicata leaf photo shows fairly smooth edges, exactly like lorax's photo in posting #11. From the leaf edges then, I would ID as G. tinctoria the original plant, shown in posting #9, and the VanDusen plants in #15, #25 (original one is also in that posting again) and #36. Except that the closeup that's 4 of 12 in posting #15 does seem to have smoother edges. Same plant as the others in the first group of 8 photos in that posting. I didn't seem to be into the leaves at UBCBG - here's the best I can do for a leaf edge.


From the leaf shape, the original plant, at the bottom of posting #3, has several cup-shaped leaves like the Strybing tinctoria in posting #36. Well, so do the VanDusen plants in posting #36. In the shade in the background at Strybing, it looks like there are a few flatter leaves too.

Rumpled leaves on G. tinctoria? Here's a photo I took of the original plant on May 17.


I think colour has to be ignored. All these plants exhibit flowers of every colour, stems of every colour, and a few young leaves with red veins. Surely soil and amount of sun affect that, here anyway.

We can ignore the statement from your second link about the chances of its being tinctoria are 99% in the US, since photos here are in botanical gardens or planted by the Parks Board, which can obtain anything.

Anyway, they were useful links except I'm more confused than I was yesterday.

I see a photo of G. mexicana on page 2 of your second link. At least it looks different with those convex leaf surfaces and more even scalloped edges.

 

Re: seen around town now

I clearly don't have this yet. Of two Gunnera plants at the Rose Garden in Stanley Park, this was the smaller, with inflorescences that look like the G. manicata.


This plant was huge. I'd have said definitely G. manicata, but the inflorescences were more compact, fitting maf's description of G. tinctoria except that they were large. I couldn't measure them. And in the second photo, the leaves are quite cup-shaped.


I've given up on the webbing stuff - I have no idea if I've seen tinctoria scales and how they'd look different and I couldn't get near these anyway.

 

Re: seen around town now

Both look more like G. manicata to me. My tinctoria is still in recovery mode so no flowers to post pictures of this year. If I go anywhere that has both this summer, I will take comparison photographs and post in this thread.

 

This thread started life as a stumper, when I didn't know I cared which Gunnera I was posting. I've moved it here to Plant ID's, as I was challenged to identify the species. I'm still challenged.
---------------------

Back to UBCBG, the one that Douglas and maf think is Gunnera tinctoria. Some of the leaves are taller than that nice man who let me take his photo, as are some of the leaves in Eric Hunt's tinctoria photo. This plant is nearly twenty years old, so if it was going to get hefty, it would have done so by now. It does not seem overall to be as large as the other park specimens I've posted and that inflorescence is positively delicate. I think it's the same one as in the first posting of this plant (posting #32) almost three weeks ago, not grown any larger.



Then guess what, I just noticed a gunnera almost across the street from me, about the same size as the UBC plant. I'm unable to reach that ledge above the leaves when I stretch my arms. But a man across the street doing a little guerrilla boulevard planting said he planted it four years ago, purchased from a nursery, but he only knew that it as a gunnera. To me, the inflorescences fit maf's G. manicata description, though they're nowhere near as large as on the mature plants posted here. I still can't make any sense of the bracts and webbing story.

 

Hmmm!
I knew this wasn't going to be easy.
You have earned by admiration for dogged determination to get to the facts.

In the RHS "Encyclopedia of Perennials" it says...
Under Gunnera Tinctoria ...."the green prickles are usually enough to distinguish it from the red -prickled G. manicata."

Does that help?

Tried to add pics here but failed. see post below.

 

See thread above.
1. Gunnera tinctoria. Our own plant.
2. Gunnera manicata. Pic taken in Glendoick garden. Near Perth. Scotland

 

Thank you, Silver surfer, no it doesn't help. All those ones above, that maf was pretty sure are G. manicata, show green prickles. The UBC one that's in the running for G. tinctoria shows mostly green prickles but a few red ones (second photo second row). Lorax's photo of the definitely identified G. manicata shows green prickles.

Exactly like in my biology classes.

 

Silver surfer, thanks for the photos. I hadn't seen them before I replied. How come science works for you?

Actually, I did notice a bit of red on the bristles on one of the stems, see photo in posting #30. Mostly, they seem rather white.

 

Re: seen around town now

I'm still trying to figure this out. Here's a plant at Sun Yat Sen Park in Chinatown that's quite small relative to the ones I've photographed in the parks around town, so I assumed it would be G. tinctoria. But the central stem on the flower stalk is very clearly visible.

My current operating rule of thumb is that if I can stand up straight underneath more than one of the leaves, it's G. manicata; else tinctoria.

 

Have have you guys considered the issue of crossing & intermediate types becoming the norm e.g. Lithops spp.? Hybridization is pretty common. Mind you, I don't even know how Gunneras are propagated commercially.

FYI hybridization is my fallback excuse when I can't clearly distinguish between 2 species/varieties - I get caught-out though when someone points out that propagation is asexual in that species or group or they are F1 hybrids or such. Darn.

 

http://www.plantsystematics.org/imgs/dws/r/Gunneraceae_Gunnera_tinctoria_33712.html
This link illustrates tinctoria inflor. Think you have G. manicata

 

I think it's time to rename the UBC one to G. tinctoria. All the inflorescences today look just like the ones at Susan's photo link in the previous posting. It's August now, and I'm starting to get it, after seeing the UBC plant today. G. tinctoria inflorescences don't get 30cm wide and rangy-looking.

And there was only one leaf stem that I could have stood under.

 

these recent photos do indeed look identical to those in the plant systematic link. good perseverance Wendy....