pond depth

[Red Robin]

Originally Posted by tom00_uk

seems strange that you would want to have Crassula helmsii (ASS) in your water body, its on the most wanted list for its impacts and here you are allowing it to grow.

....Nowt stranger than folk . It arrived in a basket of Japanese Water Irises (also alien invasive?) and I don't find it a problem to control - Quite the contrary and so far I like what it provides.

Originally Posted by tom00_uk

I like lilly flowers but with only a 3m by 10m ish surface area i decided to forgo them and went with a water hawthorn as its not classed as invasive in the UK, though is listed in NZ as such. It flowers a number of times over the year from early spring into late autumn

....Water Hawthorn would look rather messy in my small pond, besides which I was given my water lilies and like them and what they provide. But I can see that the hawthorn is a very good alternative.

I'm not a eugenical ecologist nor a rigid conservationist - I'm of the opinion we should enjoy what we've got, wherever it comes from. ETTO (Each To Their Own) [RedRobin dons his flameproofs and helmet]

[King Edward]

Originally Posted by Red Robin

....I would agree if you were saying that no other plants were in a pond but water lilies actually provide a lot of benefits for wildlife - Just different benefits to most other plants. I think the best setup is a healthy mixture of plant types and none in excess.

What are these benefits (which aren't provided by other aquatics)? As I said, I'm not saying that people shouldn't grow lilies (or water hawthorn) if they like them, just that I wouldn't choose them on the basis that they're good for wildlife. The flowers are ornamental and obviously attract some flying insects (especially beetles), but their underwater structure is minimal. Also, in larger ponds, lilies are liable to grow very vigorously and take over.

As far as I know the Japanese Irises aren't invasive.