Native Americans Were Able to Prevent the Encroachment of Trees

question 87

Multiple Choice

Native Americans were able to prevent the encroachment of trees and maintain the tallgrass prairies by

• A) establishing an extensive irrigation system to increase soil moisture, thus favoring grasses.
• B) plowing much of the land for agriculture.
• C) restricting the migrations of bison, which caused the bison to browse heavily on tree seedlings and thus kill them.
• D) setting fires periodically to kill the trees.
• E) clear- cutting the forests for timber and fuel.

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Definitions:

Elastic Stockings

Specially designed hosiery that exerts pressure on the legs to improve blood flow, often used to prevent or treat venous disorders.

Vascular Disease

A class of diseases of the blood vessels, often leading to a reduced flow of blood to organs and tissues.

Fungal Infection

An infection caused by fungi, ranging from superficial skin conditions to more serious systemic infections.

Ringworm

A fungal infection of the skin, characterized by ring-shaped, red, itchy patches.