Ability to: Read and write English at a level required for successful job performance; recognize the more common plant diseases and insect pests and approved methods and materials used in controlling and eradicating them; recognize the more common species of ornamental shrubs, trees, and flowers grown in California; follow oral and written directions; direct the work of inmate, ward, resident, or patient helpers. Knowledge of: Proper methods of planting, cultivating, and caring for hedges, ornamental trees, shrubs, lawns and flowers; gardening materials, tools, and equipment, and their use and care; approved methods and materials used in controlling and eradicating common plant diseases and insect pests.