I have collected this plant from the soil in a park in Belgium. I thought it was a child of a plant which was growing nearby but when the leaves started to grow I realised it is a different plant.
When I was collecting it, it was at the stage of having only the seed leaves (still visible in the photo) which are elongated and about 2.5 cm long. In the park, on the ground from where I collected it, these plants were growing in large quantity close to each other. After about 1 week from bringing it home the leaves started to appear. Now about 3 weeks later the leaves are about 2-3 cm long.
Could you help me identify it?
First of all, this plant is very abundant in the park but I can also spot it in other places, e.g. close to sidewalks within a walking distance from this park.
This is the plant in the original environment from where I collected it:
I could also find it growing in a pocket of a tree - this suggests to me that the seeds might have fell from a height, so this plant might be a tree (?)
Here are some further photos of surrounding plants that might be a hint for you: