The apple tree in the middle of the photo is where the nest is located. I startled a robin in the tree a few days ago and looked around and found the nest. It is on the left side of the tree, near the bottom of the branches (about 1/3 of the way up the tree. I sat in the shed on a hay bale to watch the nest. It was hard to photograph because the leaves are so dense around the nest. The nest appears to be made of a lot of dry grass. I didn't want to poke the nest, but I suspect there is also mud holding the nest together. The nest is round in shape and approximately 5"-6" across. There are at least 4 eggs in this nest! Here is the photo of me looking into the nest with the help of a mirror.

I am assuming that the nest is in the incubation stage because there are eggs, but no adults came back to sit on the nest while I was there. One adult robin came close, making small noises, but did not settle on the nest. I observed 2 robins chasing each other across the driveway at one point. Then I saw what appeared to be a pair because they were following each other companionably. They came to rest on the lawn across from the nest. I wonder how long those eggs can last without being incubated? I know that chickens rarely leave the nest when they are incubating eggs.

Here is the photo of the adult robins on the lawn.

They are very hard to see.

I looked up American Robin at https://www.allaboutbirds.org/guide/American_Robin/lifehistory. They live in this area year-round and have a very wide breeding range, covering most of North America. The incubation period is 12-14 days. This nest is located exactly where this web page says it will be ". . .typically in the lower half of a tree. .. "
According to this website: http://animals.mom.me/differences-between-male-female-american-robins-8722.html, "The female incubates her eggs once they arrive in the spring, and the male will occasionally be observed bringing food to her." That means the bird I startled off the nest was the female. I wonder if she will become used to me sitting in the shed and stay on the nest? Both parents also feed the young. I am looking forward to being able to observe this too.