Petasites

[cohan]

A bit different from the little daisies of most of this board! and probably a bit rampant for most gardens, still Petasites are prominent wildflowers here, and I will be trying some in garden beds not too near anything delicate! I was talking about them on another thread, and thought it made sense to give them their own searchable thread....
Here's a repeat of that message...
...as I've mentioned, we have plants that look like sagittatus, plants that look like frigidus v palmatus, and and every variation between the two. The 'pure' sagitattus tend to be in more open (though not always, they still take some shade at times) and wet areas, the 'pure' palmatus are in woodland areas, not really dry spots, but not necessarily wet, and the intermediate forms can be in open wet places through the wetter edges of mesic woods; Flowers of all are similar, though there are variations between plants with more or less female/male flowers, and some plants that have more purple on backs of ligules etc; I haven't clearly tied those flower differences to leaf differences, except that the mesic woodland (palmatus forms) plants don't flower much, just the occasional inflorescence, which is usually more open and less showy than the others...
here are a few photos of flowers, showing some of the variation- some of which is also age of inflorescence of course; these are mostly sagittatus types, still digging for a palmatus inflo..

[cohan]

I should add, tying flower types to leaves is trickier, since plants are not in leaf when flowering starts, and don't all flower and leaf at the same time/speed etc, plus we have so many of these various populations, that real tracking would need a bit more focussed approach than I have used so far- I'd need to put markers at sites of flowering and go back later to record leaves...
Here is an inflorescence typical of the woodland flowering plants- again they flower much less- not sure if that's due to greater shade or inherent..
Trond mentioned they look spreading- they certainly are, all forms, and in some areas in the woodland the palmatus and intermediate plants make a very lovely ground cover with other low plants (never exclusive) and the leaves are beautiful throughout the season, from unfurling through subtle fall colours..
And a palmatus leaf in spring, not the same plant, though..

[cohan]

Some images of sagittatus type leaves when just emerging..

[Hoy]

Cohan, do you say that both the palmate and the sagittate leaves are the same species?

[cohan]

Trond, I claim no special insights into the taxonomy- my impression is that there are places where the two species grow distinctly, so they may well deserve species rank; I only comment that in my area they are so mixed in many populations, that I wonder whether the ones that do look distinct are really so at the genetic level. That is to say, do I have some of each species pure plus hybrid intermediate forms growing around them, or are all or most of the plants in my area hybrid to some degree, with varying expression of the traits of one species or another?
I don't have the knowledge or tools to make that determination!
I should point out that when I say the various forms grow near one another, I don't mean in distinct populations a kilometer apart or even 500 meters- at times the different leaf forms could be side by side, other times a few meters, and you might have a large group many meter across of one type, but right at the edge of that colony (perhaps those groups are single clones?) there could be plants of another form, etc...

[Hoy]

OK, take your point

[cohan]

I do have shots of different leaves growing side by side, I'll dig them up when I remember