Who is chief executive at the state level?

The governor of Texas is the chief executive of the state

Explanation:

and is elected by the citizens every four years. The governor must be at least 30 years old and a resident of Texas for the five years immediately before the election.

crop rotation kepy different plants in the soil instead of once constintly. when switching out plants you have different nutrients being absorbed at different speeds and different roots growing differently therfore the spoil and water flow have to adapt and carry fresh nutrients to carry the constant changes that were going on in the soil.