Thank you for your question.  This is a highly invasive species, whose control may require use of a "horrific poison" if you want to control it.  Here is what OSU pest control says about it:  http://pnwhandbooks.dev.extension.oregonstate.edu/weed/problem-weeds/geranium-shiny-geranium-lucidum-herb-robert-geranium-robertianum

You can find commercial brands of these chemicals in garden stores.  Sorry there is no organic silver bullet.



I fear that the only control mechanisms that OSU recommends are those in the article I already furnished you.  Once a weed overcomes an area, it becomes more and more challenging to eradicate.  You are certainly welcome to use goats, but there is no scientific evidence to suggest they can control it.  Since it is an annual plant, destruction of the flowers and seeds is the only potential control mechanism other than chemicals.