I have heard (but can't remember where) that bedstraw, otherwise known as lady's bedstraw, was used in straw mattresses to make them softer and pleasant smelling. It has tiny yellow flowers.

What I know as goose grass, also known as cleavers though this name can also be used for burdock with its clinging seed heads, has tiny white flowers and clinging stems and leaves. When I was a child, children used to say that if you had it clinging to your clothes it meant that you were in love - presumably because you would have been dallying with your loved one in hedgerows or overgrown places out of sight.