1st on the left is Plaintain (Buckhorn), next a kind of foxtail grass, can't identify the creeper on the right hand side (too blurry when I enlarged it). 2nd pic looks like prickly pigweed, then maybe a bentgrass species, but I'm not sure, next another possible bentgrass and another yellow oxalis (yellow oxalis can look different depending on age (small, compact when 1st comes up), tall and leggy with long thick stems when mature and has plenty of water) but you can always identify it by the indented, heart shape leaf (shamrocks are in the oxalis family) which differentiates it from the clovers. There are other plants that have that bentgrass look that aren't grasses at all, I could tell better if it had a seed head. If it develops an obvious flower, it isn't a grass. Actually, you have so far, fairly decent weeds, all edible, provided the grass really is a grass. If it isn't the chickens probably won't be so eager to eat it. All grasses are edible if they are truly a grass (horsetail grass, which grows around water, is not a grass at all and is poisonous, but that would most likely not be in your backyard).
