What type of plant is this - I currently just call it a weed?

Question

The plant grows around new england, probably nation wide. It grows in gardens, unkempt lawns, and the edge of forests. It's seeds are black, 1.5cm long tapering into an arrow head shape with two hooks at the broad end. You know you've walked past the plant because your legs are covered with up to hundreds of them.

The plant has a thin stem with several branches that also have their own smaller branches each one ends in an odd number of leaves. Flowers are small and yellow.

Answer 1

beggars ticks...http://www.microscopy-uk.org.uk/mag/imga...

Answer 2

It's a group of species of a Daisy plant called Bidens

There are several species of these plants growing in N. England.

They are also called Sticktights, or Spanish Needles.

That is a unique adaption of seed dispersal after a while the seeds drop.

It's a native wildflower and not a weed at all.

Answer 3

When it comes to keying plants, every detail is crucial in describing them.

Can you describe the flower in more detail?  How many petals? How are petals arranged? How many stamen?  Are stamen superior or inferior to the stigma?  Are the petals fused or separate?  Are the seeds in a pod?

Answer 4

It's called shepherd's needle.  Bidens sp.