The beginning of the novel introduces us to an area outside of Soledad in California during the Great Depression.
In the beginning of the story, we learn that the men are somewhere distant from civilization. They are not on the ranch yet. If we pay attention, we learn that they are in California. You can tell all of this from the first sentence.
A few miles south of Soledad, the Salinas River drops in close to the hillside bank and runs deep and green. The water is warm too, for it has slipped twinkling over the yellow sands in the sunlight before reaching the narrow pool. (Ch. 1)
From the mention of Soledad and Salinas, we know that it is California where the men are stopping. Also, there is mention of the Galiban Mountains. There are a lot of animals, so there must not be many people around. This is close to the ranch, however, because while there are not many people around, people do come by.
In front of the low horizontal limb of a giant sycamore there is an ash pile made by many fires; the limb is worn smooth by men who have sat on it. (Ch. 1)
From the way the men dress, “denim trousers and in denim coats with brass buttons” and “black, shapeless hats” and carrying blanket rolls, we can guess that this takes place sometime in the past. The men’s’ dinner will also give you some clues.
“I got three cans of beans in my bindle. You get a fire ready. I'll give you a match when you get the sticks together. Then we'll heat the beans and have supper." (Ch. 1)
People with a knowledge of history will guess the Great Depression by the way the men are dressed, the fact that they eat canned beans and talk about ketchup, and the talk about the bus and the ranch. It was a time when many men traveled around the county, especially California, looking for work on ranches.
All of these elements—the description of the landscape, what the men wear, and even what they eat—make up the setting. They introduce us to where the men are, and when the scene is taking place. From this, we can guess what is going to be happening in the story. We know that the story will take place on a ranch.