Arborists work on the planting, maintenance, and care of trees and some other plants. Arborists duties include evaluating the health of trees, providing a tree care plan, and then implementing the plan by providing services like pruning, fertilization, planting, and insect and disease control. Arborists may work in-house for a nursery, landscaping or tree care company, property developer, or a state or national parks service. Often, they work as consultants, providing one time or scheduled services for any business or person who needs help with their tree care responsibilities.