Persicaria lanigera?

Post by **MWP admin** » Tue Jan 22, 2008 11:58 am

I was wondering what species this Persicaria is. The leaves were darker, and somehow smaller from the Persicaria lanigera I and il-Pine have seen at Wied il-Ghajn, but the inflorescence is similar.

Confused?

RB · Post by RB » Tue Jan 22, 2008 1:18 pm

Lots of that (as per pic) at Bahrija. The ones in M'Scala - referring to the ones growing in the dammed-up valley that leads from Zabbar? If so, definitely different to this pic.

Can't help with either except just to point out /confirm the very obvious differences.

RB

D. Cilia · Post by **D. Cilia** » Tue Jan 22, 2008 1:45 pm

That is one beautiful shrub!

Post by **MWP admin** » Tue Jan 22, 2008 1:55 pm

Regards the location, there is something reated (and a photo) here:

http://maltawildplants.com/forum/viewto ... t=lanigera

The photo here is from M'Forn Valley. I too think that it is not quite the same 'shape' as Persicaria lanigera, but some plants vary a lot according to habitat and env conditions.

RB · Post by RB » Tue Jan 22, 2008 2:30 pm

The ones in Zabbar - M'Scala valley IIRC produce white flowers not pink, and the leaves are decidedly grey - apart from the more robust growth all over.

RB

Post by **MWP admin** » Tue Jan 22, 2008 6:07 pm

Well, given that it is not P. lanigera (I also agree that it is a good possibility), then Haslam gives two possible Polygonum species that forms spikes that aredense and stout with the flowers crowded and overlapping.

Polygonum persicaria and Polygonum lapathifolium

The latter has yellow glands which we cannot observe from the available photos. However these are described to reach a height of 80cm, and the specimen photographes was nearly as tall as me, so I would say 150cm.

I will make more work on this species unless someone is familiar with it.

Post by **MWP admin** » Tue Jan 22, 2008 6:13 pm

... Polygonum lapathifolium looks closer on a quick internet search

http://herbarivirtual.uib.es/cas-med/especie/4103.html

The other (p. persicaria) seems to have a black marking on the leaves. Just a quick note - nothing defenitive!

IL-PINE · Post by **IL-PINE** » Tue Jan 22, 2008 8:32 pm

well, I agree that it looks different than P. lanigera.
I also found a large population of Persicaria in Girgenti, might also be this or one of the other species.

Post by **MWP admin** » Tue Jan 22, 2008 8:34 pm

Hi Pine,

Can you post some pics for comparison?

IL-PINE · Post by **IL-PINE** » Wed Jan 23, 2008 1:21 pm

nope!
I thought it was the same species and I didn't even photograph!

Post by **MWP admin** » Sun Jan 27, 2008 12:01 am

From the research I did Polygonum persicaria is the best to fit my plant, though one have to see the edge of the ochre and in my photos this is not shown very well (destroyed!)

Post by **MWP admin** » Wed Aug 27, 2008 3:52 pm

RB wrote:The ones in Zabbar - M'Scala valley IIRC produce white flowers not pink, and the leaves are decidedly grey - apart from the more robust growth all over.

RB

RB, very important question - I went 2-3 times to locate the group of plants at M'Scala and I could not find them anymore. Maybe I am confusing the roads, but seems the area was taken by the new extension of the Waste Recycling Plant.

Have you seen them recently (last 3-4 months)

jackpot · Post by **jackpot** » Thu Aug 28, 2008 8:18 am

you took the wrong road- we saw the lanigeras 4 weeks ago (but at first we also took the wrong road in the same direction. Take the road from the church (park)...

Post by **MWP admin** » Thu Aug 28, 2008 4:42 pm

I try to go again soon, but now the plants are probably flowerless and seedfull! I need to check the pilosity/textire of the peduncles. I know that Persicaria (polygonum) have undergone a thourough revision and if someone happens to know a source or have some related docs, kindly contact me.

RB · Post by RB » Mon Sep 01, 2008 10:04 am

As JP said it is not the Bypass but the "old" M'scala road. There is a dam and further upstream a bridge over the valley floor that leads to Bidni, usually the greatest concentration is found there, just by the bridge.

It's quite a dirty place actually!!

RB

MWP admin wrote:
RB wrote:The ones in Zabbar - M'Scala valley IIRC produce white flowers not pink, and the leaves are decidedly grey - apart from the more robust growth all over.

RB
RB, very important question - I went 2-3 times to locate the group of plants at M'Scala and I could not find them anymore. Maybe I am confusing the roads, but seems the area was taken by the new extension of the Waste Recycling Plant.

Have you seen them recently (last 3-4 months)

Post by **MWP admin** » Mon Sep 01, 2008 10:08 am

Dear RB and JP

Thanks for you memory refresh - I was taking the wrong road. I went a few days ago to check some morphological features of this plant which were flowerless and fruitless.

The population has decreased drastically, more than 50% is lost I would say.

Check image below with one taken 2 years ago

Post by **MWP admin** » Mon Sep 01, 2008 10:14 am

Population of Persicaria lanigera in 2006 (now seeing the photo again - I would say even that it was 3 times as much

)

IL-PINE · Post by **IL-PINE** » Mon Sep 01, 2008 2:21 pm

istra yes it decreased a lot! In fact I took a photograph of MWP in that period and it seemed he was in the Amazon forest surrounded by plants! Well, need to go to Girgenti to see the population I had found in the same period.
BTw I'm back

RB · Post by RB » Mon Sep 01, 2008 3:28 pm

I think the pop will always be very variable depending on the rain patterns. Simply put, if it rains heavily late in the season, the ones further down the valley will be totally submerged for days and will die. The habitat is not natural and thus susceptible to these extreme variations. I would say however that without the dam, the pop would possibly just disappear completely.

RB

jackpot · Post by **jackpot** » Tue Sep 02, 2008 8:20 am

agree 100% RB (hope you bought it meanwhile- I NEED THE MONEY!!)

Post by **MWP admin** » Wed Sep 03, 2008 1:14 pm

Welcome Mr. Pine! Hope you had a nice time!

back to the topic, the original plant I posted do not fit as Persicaria lanigera, nor Persicaria maculata (Polygonum persicaria) and so I think it is one of the varieties of Persicaria lapathifolium. I ruled out P. glabra too.

The ochrae were glabrous (entire) to finely ciliated but not dented/serrated, while the peduncles possessed small yellow glands.

I know that the Polygonum have recentely been revised with new taxons put into the Persicaria genus. If you know some doc/paper in regards please post it up.

MaltaWildplants.com FORUM

Persicaria lanigera?

Persicaria lanigera?

Thanks for refreshing the memory