Poll: what kind of plant or weed do we have in are apartment complex?

Question

we have some weed or plants growing similar to this plant or weed http://weeds.cropsci.uiuc.edu/images/Poison%20hemlock/ with rounder leaves and smaller are the plants hazardous to pet or people please help if possible?

Answer 1

ragweed ?

Answer 2

Old world climbing fern and japanese climbing fern look similar to your photo.  They are exotic invasive plants that have invaded the south.  Take a look and see if that is what you have.

http://edis.ifas.ufl.edu/AG122

http://aquat1.ifas.ufl.edu/lygjap.html