When I tried to plant some plants and dug up a hole in my front yard, it appeared that there is a waterproof, at least it appeared to me so, tarp under the soil and mulch mixture, and it extends to a very large area, probably as large as most of my yard. The material of the tarp looks similar to this.
What is it called? What is its function/purpose? When planting perennial plants, should I dig through this tarp or not? If not, the depth of the soil/mulch does not seem deep enough for the plants to develop a large root system.
This yard is located in Pacific Northwest which alternates between a rainy fall-winter season and a dry summer season.