Wildflowers: Identify these two plant that are similar with burrs

I have photo of two probably invasive wildflowers that I have been trying to identify but I cannot seem to find them on the net. The are very similar but one has white flowers and grows in the woods, and the other has yellow flowers but grows in the prairie.

Any help identifying these two, I would be very grateful.

 

2. Looks like Geum urbanum. Common name Wood Avens.

http://images.google.co.uk/images?h...um=0&q=geum urbanum&um=1&ie=UTF-8&sa=N&tab=wi