ISA Certified Arborist Practice Exam

This is because macronutrients (choice A) refers to the essential nutrients needed in large quantities for plants, such as nitrogen (choice B). Water holding capacity (choice D) refers to the maximum amount of water that soil can hold, while infiltration rate (choice C) specifically refers to the speed at which water moves into the soil. Therefore, infiltration rate is the most accurate term that describes the rate at which water soaks into the soil.