Galium

Galium is a large genus of annual and perennial herbaceous plants in the family Rubiaceae, occurring in the temperate zones of both the Northern and Southern Hemispheres. Some species are informally known as bedstraw.

There are over 600 species of Galium, with estimates of 629 to 650 as of 2013. The field madder, Sherardia arvensis, is a close relative and may be confused with a tiny bedstraw. Asperula is also a closely related genus; some species of Galium (such as woodruff, G. odoratum) are occasionally placed therein.

Genetic variability
The phenotypic plasticity and genetic variability of this species allows it to be constantly shifting to best fit its environment adjusting life cycles, seed germination, productivity, growth form, freezing tolerance, etc. Herbicides at the recommended amount is not effective enough to decrease catchweed bedstraw biomass or population, twice the amount is needed.

As invasive species
Cattle and other livestock don't often feed on this plant making it thrive and dominating over other species. G. mollugo in particular, is a thriving invasive species since it can go in and dominate in areas where other alien species wouldn't be able to, growing very fast in best conditions.