The not-invasive Bulrush

My naturally colonised Bulrush, a widely hated ‘invasive’ plant, is still showing none of its reputed triffid nature in my pond.

It’s now midsummer and we’ve got a total of five stems.

Most interesting, the plants are practically dwarfs – mine are about 70 cm tall,

My Bulrush 28 June 2009

only a quarter of the 3 m they can reach.

I think – though I’ve no proof of this – the very low levels of nutrients in the pond are keeping them stunted. I still don’t really anticipate them taking over, not for a few years yet anyway.

Some questions

Matt asks:

M: Do the larvae of Broad-bodied Chasers live in streams?

J: No, they seem never to be found in streams and rivers. Your’s must have come from another pond, lake or very slow moving ditch somewhere.

M: Can sticklebacks live happily alongside other creatures or are they also quite voracious?

J: Lots of animals do live alongside sticklebacks but I think the effect they have will depend a lot on the size of pond. In a local pond down by the river near us in Abingdon, there’s a good range of animals living in a pond that also has 3-spined sticklebacks. But I suspect that when you put the sticklebacks in a small pond they’re likely to have a much bigger impact.

Sticklebacks are notorius for exterminating Great Crested Newt larvae; no doubt they would have the same effect on the smaller newts too. People sometimes go to considerable lengths to get rid of them from crested newt ponds.