Any ideas what these weeds are?

[WendyC]

I have never appreciated the differences between greater and lesser celandine. I didn't think weed 2 was a celandine as I always associate it as low growing with round fleshy leaves- that's the lesser celandine. Your one is the greater celandine. Learn something new every day!

[Two_Sheds]

3. Lords & Ladies - poisonous!

as are tulips & daffodils: but only if you eat them

[fishpond]

Many Thanks to you all for your input, much appreciated.

[phlorum]

Doesn't look like knotweed

mod edit: removed your link, the weeds posted are definately not knotweed, and with your site offering services it may be viewed that you're trying to advertise.

[andy_j]

Stab in the dark but the 4th looks a bit like my Eupatorium....a water or damp loving plant that is often seen growing along streams