Your backyard is full of wild edibles. I have found that the Dandelion is one of the best and there is no poisonous look alikes to it. You can eat the leaves which have a bitter taste but if you boil them in one change of water the are great. The roots are also edible, dig them up and cook them just like carrots.
The flowers are edible put them with other greens or by themselves as a salad (just remove the green bottom of the flower).
So next time your looking for an easy bite too eat look no further then the Dandelion.