I see a couple of types of nasty weeds. The big leafy one is Palmer's pigweed, which can grow to ten feet tall and produce thousands of seeds. The fern looking one is puncture vine, AKA goatshead, which produces pronged seeds famous for puncturing bicycle tires and children's feet.

Not a big fan of the goatshead! I've got two flat bike tires likely from this and the area I saw this in is one where I frequently have to pull prickers from the dog's paw. However, I did some reading up on aramanth and wonder if young plants are edible. I make a smoothie every morning with greens and, from what I've read, amaranth might be related to spinach. I'm an adventurous sort and a minor forager so I may do more research before adding some to my morning ritual.

On another note, this may be the answer to what my neighbors are growing in their yard. They don't speak much English and could only tell me it was Vietnamese spinach. Originally in wondered if it was malabar spinach butI now I believe it's actually in the amaranth family. I'll try to get a picture tomorrow when I'm out with the dog.

that one is eatable...but weeds are not pretty to look at