I have heliopsis (false sunflower, ox-eye) in a number of my gardens. The first 2 pictures show the leaves and stem of my heliopsis plants. The 3rd are 4th show the leaves and stem of what LOOKS like heliopsis, but the stem seems different (more square, somewhat softer, fine hairs). The new ones are coming up everywhere. Is this also heliopsis or a variety of weed that is similar in appearance?
These are the leaves of my heliopsis
The stem of my heliopsis
The leaves of the plant that MIGHT be heliopsis
The stem of the plant that MIGHT be heliopsis (note the hairs)