Originally Posted by Spider[_3_]

I'm unable to see your pic, but wonder if your plant could be Japanese
Knotweed? In this area, it is just starting to push its strong red
shoots up through local pavements and gardens. It certainly has a
massive root system. Although the leaves are not considered narrow, the
young red shoots may appear to be so as they unfurl. If it is, you need
to get rid of it as soon as possible.