637. Similar Activities

Shabbos 7:2

The 39 labors and all similar activities are the primary categories of labor. “Similar activity” means as follows: Plowing, digging and making a groove in the dirt are all considered a primary category of labor since they all involve digging in the earth and they represent the same kind of activity.

Shabbos 7:3

Similarly, whether one plants seeds, plants trees, bends tree limbs into the ground, grafts trees or prunes trees, they all represent the same primary category of labor because they all have the same goal: to make a plant grow.