Thistle trouble

Post by **MWP admin** » Thu May 03, 2007 9:20 am

There are 2 particular thistles which are quite similar and I am having difficulty to distinguish them. I am speaking of Carlina involucrata and Carthamus lanatus.

I am enclosing 2 pics of the same specimen. Can you please ID/compare with your own photos and tell me what it is.

I am attaching 2 specimens of two different species (or maybe the 4 are all the same species)

Confused!

wolf · Post by **wolf** » Thu May 03, 2007 5:12 pm

stenniejhom jaghmlu l-fjuri max - that's my method !

robcar · Post by **robcar** » Sat May 05, 2007 11:06 am

For me - dawk kollha xewk - hopeless at thistles - they tend to be summer plants when I am in botanical aestivation

Post by **MWP admin** » Sat May 05, 2007 2:15 pm

I think they re different species as one tend to have reddish stems and the other green. the leaves are also different on closer examination (not much shown on the photos here)

One must be Carlina involucrata (probably the red-stemmed one)

Hope the Germans will get free for someforum time soon.

wolf · Post by **wolf** » Sun May 06, 2007 8:58 am

wrong attitude Robcar !!!
some thistles are really beautiful stuff and worth sweating it out for... my favorite is scolymus maculatus - its stalk is like an armored dragon and its flower is quite a beauty too

Post by **MWP admin** » Sun May 06, 2007 5:22 pm

The only one I do not like is Galactites tomentosa. It is increasing rapidly and is a bugger in most fallow fields and soily wastland, leaving explorers swearing and smaller native plants struggling for light and food. There are other nasty ones but as wolf said, they have some beauty if you examine them well.

I am close to conclude that the one with red stems is Carlina involucrata. The other (with green stems) have an interesting feature. It has several threads of silk-like material running longitudinal to the stem or the leaf axis. I am not sure if it is caused by some insect/spider/larvae or it is a property of the plant.

I will post a photo of this feature soon becasue now I feel lazy!

wolf · Post by **wolf** » Sun May 06, 2007 7:09 pm

I agree completely re g. tomentosa ...it is such a bore and we shud really start eradicating it.....just last week i walked all the clay slopes between ramla and marsalforn expecting to find rare species and 90% of the flora consists of g.t ...thankfully it is not on the clay at qammieh where i was today....yet

we shud be thankful for that i think

robcar · Post by **robcar** » Sun May 06, 2007 7:43 pm

Yep wolf, you are very right indeed- I know that it is the wrong attitude and that they are actually pretty nice plants

Regarding G.tomentosa, it is a bore but the problem is not the plant in itself but rather the way in which human activities are affecting habitats - it is after all a plant that is native throughout the Mediterranean, not some South African immigrant like Oxalis

The problem is the increasing spread of disturbed ground and abandoned fallow fields, which are its favoured habitat and could be the reason why it could be spreading rapigly

jackpot · Post by **jackpot** » Mon May 07, 2007 8:50 am

what about Carthamus lanatus

Post by **MWP admin** » Mon May 07, 2007 9:05 am

Welcome back JP

There are 2 species in this post which have rather same morphology at first glance

One is red stemmed the other is not. i think one is Carthamus lanatus and the other is Carlina involucrata but which is which?

jackpot · Post by **jackpot** » Mon May 07, 2007 12:22 pm

Carthamus lanatus: the one which has not the red stem!

Post by **MWP admin** » Mon May 07, 2007 7:56 pm

Thanks. The thistle-trouble which bothered me these last 3 weeks is solved. The red-stemmed thistle must be Carlina involucrata then.