Final answer:
Counting the total number of individuals within a square or rectangle of known area, referred to as a quadrat, is a sampling method commonly used to study plants or other sessile animals.
Step-by-step explanation:
Counting the total number of individuals within a square or rectangle of known area, referred to as a quadrat, is a sampling method commonly used to study plants or other sessile animals. A quadrat is a square structure that is randomly located on the ground and used to count the number of individuals that lie within its boundaries. To obtain an accurate count using this method, the square must be placed at random locations within the habitat enough times to produce an accurate estimate.