 |
|
|
Alien or not?: |
| Author | Message |
|
Martin Senior Member Joined: 23 Feb 2003 No. of posts: 87  View other posts by Martin |
Posted: 24 Feb 2003 Fringed water lily. Dwarf, edges of the petals serrated. I could dig out a latin name on it? Is it a problem or not? Who thinks what....? |
|
Mervyn Admin Group Joined: 14 Feb 2003 No. of posts: 41 View other posts by Mervyn |
Posted: 25 Feb 2003 Martin Try Nymphoides peltata Mervyn J. COTTENDEN, CPA |
|
Martin Senior Member Joined: 23 Feb 2003 No. of posts: 87 View other posts by Martin |
Posted: 26 Feb 2003 That's the one, what do you think of it? (Do you think about it!??) |
|
Mervyn Admin Group Joined: 14 Feb 2003 No. of posts: 41 View other posts by Mervyn |
Posted: 26 Feb 2003 Martin
Quite honestly I had never heard of this before. Mervyn J. COTTENDEN, CPA |
|
Gemma Fairchild Krag Committee Joined: 14 Feb 2003 No. of posts: 193 View other posts by Gemma Fairchild |
Posted: 26 Feb 2003 As the plough is to a meadow, so Nymphoides peltata is to a pond? Scary stuff Martin, any news on its spread. I have not seen it in the wild (yet) but have seen pictures of it choking ponds. ----RAUK e-Forum---- 
|
|
David Bird Forum Specialist Joined: 17 Feb 2003 No. of posts: 515 View other posts by David Bird |
Posted: 27 Feb 2003 I did not realise when I saw the title of this section the other day that it was not to do with Alien species of herpetofauna. Alien Aquatic Macrophytes are however a subject very close to my heart and sadly neglected by herpetologists and especially pond owners who are the cause of many of the problems. I would like to say that the fringed water lily Nymphoides peltatus is thought to be native in the Thames Valley and East Anglia having been known since the 1500Æs, the present distribution is due to deliberate movement of wild plants and the release of cultivated stock which is probably from European stock. Although this species does form large dense masses I do not know of any problems with the amphibian or invertebrate population where it occurs in Dorset. I do have slides of close ups of the plant and also extensive cover of ponds in Dorset and the New Forest if they are of any use to the site and anyone has a scanner. The species which is causing a problem in Hampshire and elsewhere is the New Zealand Stonecrop Crassula helmsii which can survive in water of varying depths growing across the surface of deep water and growing up to the surface30 cm from the bottom in ponds and even on dry gravel and heathland soil under gorse in the New Forest. I t produces a dense monoculture and is a problem for rare British aquatic plants and does seem to reduce the amount of invertebrates in a pond, it also seems to dry out non permanent ponds faster in the summer which may not give some amphibians enough time to metamorphose. It is almost impossible to eradicate and can be spread by animals and on footwear. It is still being sold by garden and aquatic centres and being released into wild ponds by ôwell meaningö pond owners when they clean out there own ponds at home..Again I have slides of this species. A species that is becoming a problem in the home counties is the floating pennywort Hydrocotyle rannunculoides from N.America that is now a problem in S. & C.America. It does form huge mats and can be a problem for boats on canals and rivers but as we do not have it yet in Dorset or Hampshire I cannot comment on its effect on amphibians or aquatic invertebrates but do not think it is going to have a positive effect. British Herpetological Society Librarian and member of B.H.S Conservation Committee. Self employed Herpetological Consultant and Field Worker. |
|
GemmaJF Admin Group Joined: 25 Jan 2003 No. of posts: 2090  View other posts by GemmaJF |
Posted: 28 Feb 2003 I must admit I was thinking more along the lines of red eared terrapins and bull frogs, but invasive and noxious plants are clearly a relevant issue. For those who want to know more about these plants, information and a freely distributable fact sheet are available at: http://www.invasiveweeds.co.uk/ Thanks to Jon Huckle for permissions
Gemma Fairchild, Independent Ecological Consultant |
- Alien or not? |