A tornado strips out a section of a forest. What type of succession is this? Why?

Secondary succession

Explanation:

A secondary succession is when a type of disturbance happens when there is already soil present. In this case, it has already started out with a forest (including plants, trees, and wildlife). Other examples of a secondary succession include a wildfire, hurricane, flood, or human destruction.

This is different from a primary succession. A primary succession occurs when  there is no soil present.

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.

multiply it by 5 in order for you to understand i cant give an exact answer.