Japanese Knotweed as a host plant

[themoth]

I've been trying to find out (with great difficulty) if Japanese Knotweed is used as a host plant by any native butterfly and moth caterpillars. Does anybody know?????

[Tursiops2]

Hi themoth, welcome to the forum.
Can't answer your question for certain, but judging by the difficulties in finding a natural control for the stuff, I doubt if there are many natives feeding on it.

A recent post on this topic:http://www.wildaboutbritain.co.uk/fo...eed#post136863

T2

[Wild-Woman]

The only thing I've seen on it is Harlequin ladybirds....another non native species! Think they must be sticking together!

[aeshna5]

I'm not aware of any, but it wouldn't surprise if something like a Vapourer larva might have a go, as they seem to eat most things!

I know under lab conditions there were some trials with natural predators from Japan including a couple of beetles.

[Neil Jones]

I run some experiments with Garden Tiger Moths some years ago. I didn't find anything they wouldn't eat but they tended to take other things in preference to Japanese Knotweed.

I don't know if they could actually be reared to maturity but I wouldn't be surprised.
The Late Miriam Rothschild had them eating Cannabis as part of a research project but they didn't do very well on it apparently.

[Dan Salter]

According to Richard Mabeys Flora Brittania the onyl thing that feeds on the plant is some country oik children...as it tastes a bit like rhubarb !

[Neil Jones]

Originally Posted by Dan Salter

According to Richard Mabeys Flora Brittania the onyl thing that feeds on the plant is some country oik children...as it tastes a bit like rhubarb !

Oh apparently it is edible. I have never tried it though. Here are some recipes
Recipes Page

[poschiavanus]

Here's a list of insects on Japanese Knotweed:

The Phytophagous Insects for Fallopia japonica

The Ecological Flora of the British Isles is a good place to start looking for insects associated with a given plant. However it is not complete (particularly for Lepidoptera). Malcolm Storey's bioimages site often has information (for instance for weevils & other beetles) which complements the ecoflora.

HTH,

poschiavanus

[aeshna5]

Originally Posted by poschiavanus

Here's a list of insects on Japanese Knotweed:

The Phytophagous Insects for Fallopia japonica

The Ecological Flora of the British Isles is a good place to start looking for insects associated with a given plant. However it is not complete (particularly for Lepidoptera). Malcolm Storey's bioimages site often has information (for instance for weevils & other beetles) which complements the ecoflora.

HTH,

poschiavanus

I'm amazed to see Peacock, Inachis io, given as a species that feeds on this plant-certainly not given in any books I can find + I've never encountered this species on it. Will be interesting to see the reference given.

Thanks for the useful links.

[poschiavanus]

I hadn't looked at the list: Peacock is a surprise.

I also forgot to provide a link to an american project photographing wildlife on Japanese Knotweed. It is on flickr.

poschiavanus