A plant that looks very similar to the better-known Japanese Knotweed is the Giant Knotweed. It is also a non native invasive plant. However, as the name suggests, it grows taller than Japanese Knotweed and it also has leaves that are more heart-shaped.
Below are some photos from a site survey we carried out in Surrey. These only demonstrate a few weeks growth since it was relatively early on in the growing season.
You can see how large the leaf of this Giant Knotweed is when compared to a hand!
Giant knotweed can be treated in a similar way to Japanese knotweed - just a little patience and the plant will be happily managed.