Invaded by Weeds

I'm in a losing battle with my weeds. Why are they my weeds? Because they're in my yard. I recently had fairly extensive work done on my backyard. By the time the fun cosmetic part came along, I was out of funds to create a proper yard (gopher wire, weed killer, sod, etc) and so sprinkled grass seed, watered, and vigilantly stood guard as the neighborhood cats tried to sneak into the yard that for so long had been the local feline public restroom. Well-meaning friends would come by, enjoy my happiness for a moment, and then warn me about weeds. I'd again explain that I hadn't wanted to use poison. They'd again explain it was necessary, but would graciously end with an unconvincing "Well maybe it will be ok..."

One day, amazingly! little random tufts of beautiful grass began to sprout, culminating in a full-on if spotty green backyard that wowed my family and me upon our return from vacation. A week after our return, I'm busy counting on my fingers the friends who are well within their rights to say "I told you so." (Five minutes after this posting, I ran out of fingers.)

I started noticing some weeds that look like fancy mini lettuces, the kind most people don't really like but eat because they're upscale. At first I mentally pshawed it. After all, weeds are green too. They've since become more prominent. I'm still on the fence (punny I know) as to whether or not this is really a problem. Some spots have a few weeds here and there, while others are ridden with them. Some weeds are fine, right? Too many, though, and the ground almost looks sick with chicken pox or measles. Maybe it's just a question of balance...