Use it for short, quick problems such as clarifying an assignment, telling me you will miss class, or making an appointment. I would rather talk with you in person when there is a problem of understanding the material or an assignment. I welcome your visits.
Appointments are always a good idea.
If you make an appointment, try to keep it, and call if you must break it. I will try to contact you if I am unable to make an appointment. U.S. agriculture is a remarkable industry. The industry has been the object of conscious and specific federal, state, and local policies almost from the time Europeans first settled on the North American continent. Nearly everything associated with agriculture is controlled by some policy.