plant ID

[dan4x4]

Found this growing in the streams running to Ennerdale Water on the weekend. Does anybody know what it is? Well I say stream, it was a footpath but they sometimes become streams.

 

[Tim Harrison]

Looks like a Potamogeton sp. of some sort.

 

[dw1305]

Hi all,

Found this growing in the streams running to Ennerdale Water on the weekend. Does anybody know what it is? Well I say stream, it was a footpath but they sometimes become streams.

I agree with @Tim Harrison it is a Potamogeton, and probably (almost certainly) <"P. polygonifolius">.

cheers Darrel

 

[Edvet]

Potamogeton are very hardy it seems. In an above ground pond at my golfclub there are Potamogetons. They drain it during winter, and after filling it in spring they re-appear spontaneously, amazing.

 

[zozo]

Or it's the P. natans, they can grow together in the same habitat.. Even well trained observers find it tricky to keep them apart. I'm not fully sure, because i'm not well trained enough. But the major difference between the 2 is the submersed grow form is rather elongated which the natans doesn't have the natan submersed form is rather spicky like grass but different. I guess that's what @dw1305 spotted, the submersed leaf form. ??

Here is a nice British website Herbaria United with pictures and locations, even Dutch botanic databases use it's illustrations as reference, that's how i found it.
http://herbariaunited.org/specimens...e=&placeid=&Inst=all&search=search#searchlist

they re-appear spontaneously

That's a typical P. polygonifolius it can withstand drought very well and it can easily grow like this

While natans is a typical floater never realy pops over the surface if it does it dries out rather quickly.

I've got the P. natans and P. Gayi in the garden and both in the same aquarium on dirt soil (now indoors). (Dirt soil x Potamogeton = Big mistake ). Vigorous runners once it's firmly rooted there is no stopping it. It will take over the entire tank. The P.gayi all tho tropical survives mild winters outdoor even mild frost. It's a potential new exotic spp. If not dispossed correctly by hobby growers or careless professional nurseries it will one day certainly popup in european water if our temps keep rising like this.

 

[dw1305]

Hi all,

Or it's the P. natans, they can grow together in the same habitat..

It was the habitat that made me think P. polygonifolius was most likely, but as you say they are difficult to ID to species.

As you go N. and W. in the UK you tend to find "aquatic" plants in more terrestrial situations.

cheers Darrel

 

[zozo]

Hi all,It was the habitat that made me think P. polygonifolius was most likely, but as you say they are difficult to ID to species.

As you go N. and W. in the UK you tend to find "aquatic" plants in more terrestrial situations.

cheers Darrel

That's knowing the area, the situations and training combined.. I never been to the Britsh isles, didn't even think of that option.. I think i have seen P. polygonifolius, but couldn't get my hands on it, so i can't be sure.. Than i have to take my references from the available lit. etc. so far. The most obvious difference to determine seems the submersed leaf shape.

If TT realy is interested in this, catch some and plant it in a tank or so and look for young submersed grow form. Or look again in spring time since it's a very early growing plant.

Bottom right example, the elongated narrow submersed leaf.. The natans doesn't have this, it only developes a submersed leafstalk looking like a blade of grass, the actual leaf develops already floating.

 

[dw1305]

Hi all,

That's knowing the area, the situations and training combined.. I never been to the Britsh isles, didn't even think of that option.. I think i have seen P. polygonifolius, but couldn't get my hands on it, so i can't be sure.. Than i have to take my references from the available lit. etc. so far. The most obvious difference to determine seems the submersed leaf shape.

Yes, there isn't much difference in the leaf shape between submerged and floating leaves. There is another rare boreal species of pond-weed in the N. UK, Potamogeton gramineus, which has submerged leaves that are broader than P. natans, but not as broad a P. polygonifolius. Potamogeton natans is likely to turn up anywhere in the UK, usually in still water, but sometimes in streams, where it often just has submerged leaves.

The photo you have from (Carl Farmer's Skye flora) is pretty much how P. polygonifolius looks when it has grown "dry".

I think P. polygonifolius is on the red-list in the Netherlands, but it is <"common away from the S. of England"> in the UK. In the west anywhere you have wet, acidic conditions you can find it, sometimes in "unsuitable looking" places where it dries out in the summer.

cheers Darrel

 

[zozo]

I think P. polygonifolius is on the red-list in the Netherlands

Not realy, seems to be rather common and not under threat..
https://www.verspreidingsatlas.nl/1000

The red dots is where it all is observed and reported. I live all the way down in the orange region, bellow the last 5 red dots.. Hence i can't realy find it. It's never been spotted much down there. @Edvet he must be able to find it, looking at the chart it must grow out of his ears..

And it is not a plant available in the pond shops next to the natans and crispus which are the common ones. I did put the natans in the aquarium, but that's not the most decorative one in submersed form. And the crispus which is considered a pest i can pick up at a local pond, but pest or not this also seems to be a picky one it did't like the new parameters that much and died.

 

[Edvet]

Not realy in my area either

 

[zozo]

Not realy in my area either

No? Oh yeah no i see that's the border line..

 

[Edvet]

Looks like they don't like clay

 

[dw1305]

Hi all,

Not realy, seems to be rather common and not under threat..

I did wonder, I got that bit <"via Wikipedia">.

cheers Darrel

 

[dan4x4]

Im going to take my bucket next time so I can take some to try in my pot ponds. I've left my potagmogeton gayi outside, it looks dead it'll be interesting to see if grows back when it starts to warm up.

Thanks for the info I really enjoyed reading this

 

[zozo]

I've left my potagmogeton gayi outside, it looks dead

I've got mine for over 2 years now outdoors, last winter it was in the ice and still looking green. Could be an overnight flash freeze dunno didn'tmonitor it so well. But what was in deeper water came back. This year we yet didn't have any real frost, i'll see tomorow if i have some green P. gayi left in the garden again this year. I'll take a pic if i find any.

I did wonder, I got that bit <"via Wikipedia">.

I red complaints before, that Wiki often contains mistakes and is not the most thrust worthy reference source. . it seems Wikipedia is a public open source, any reader can edit content. Look left hand next to the search box at the top, there is the Edit tab. I never tried, so i have no idea if and how this is checked if someone does edit content. But it seems that's the reason for Wikipedia often containing faulty information.

 

[zozo]

Here it is Januari, mild frost at night average day temp 5°C or less.. Aponogeton Gayi still green and growing..

Also H. tripartita is still going strong..

 

[Ray]

I've got the P. natans and P. Gayi in the garden and both in the same aquarium on dirt soil (now indoors). (Dirt soil x Potamogeton = Big mistake ). Vigorous runners once it's firmly rooted there is no stopping it. It will take over the entire tank. The P.gayi all tho tropical survives mild winters outdoor even mild frost. It's a potential new exotic spp. If not dispossed correctly by hobby growers or careless professional nurseries it will one day certainly popup in european water if our temps keep rising like this.

Sorry to revive this thread, but when I was a kid there was a pond near me with what looked like P. Natans across the whole surface. For years I’ve been thinking “that’s a much more manageable size for the aquarium than the so called dwarf lilly species” and finally did the googling to figure out what it was.

@zozo - are you saying it’s even more of a beast at tank takeovers than crypts and nobody would want to grow it? Or does it need a dormant winter period and wouldn’t last? Also if you are still growing it would you be so kind as to post a shot of what it looks like from under water?

Thank you,

 

[zozo]

are you saying it’s even more of a beast at tank takeovers than crypts

I dunno I never grew crypt in the same condition... Still growing P. natans in the garden, i did cut all out at the bottom and there was no green foliage left. But it keeps coming back from the roots left in the soil.

post a shot of what it looks like from under water?

There isn't much interesting to see underwater, currently, i have no picture of it, but Google images does.

The submerged leaves are only temporary, it finally will reach the surface and spread on floating with only having naked stems submerged.

Not really a decorative plant for submerged purpose, but definitively a great plant to keep waterbodies stable from high bioload it's a resource hog. What i grew indoors didn't show any sign of dormancy, it's an evergreen in tropical conditions.

 

[Ray]

Thanks for that @zozo - very much appreciated, the Willem Kolvoort images are lovely and don't pop up in Google image search here in Switzerland. I'll add
Potamogeton natans to my "to do" list and try to grow it instead of a lilly in a scape one of these days...

 

[zozo]

Thanks for that @zozo - very much appreciated, the Willem Kolvoort images are lovely and don't pop up in Google image search here in Switzerland. I'll add
Potamogeton natans to my "to do" list and try to grow it instead of a lilly in a scape one of these days...

Some lilies can be pretty nice for an aquarium if enough light is provided... A few years ago i bougth a small variety from a German nursery via www.ebay.de

https://www.ukaps.org/forum/threads/i-think-i-am-in-love.37099/

It's this one still for sale
https://www.ebay.de/itm/Zwergseeros...111793?hash=item1c46b157f1:g:gggAAOSwQItUIyO0

And i can sincerely recommend this one, still growing it today. Indoors and Outdoors