Giant Ragweed is a tall, herbaceous plant native to North America, often found in fields, roadsides, and disturbed areas. It can grow up to 15 feet high and has large, lobed leaves. The plant produces greenish-yellow flowers that bloom in late summer and fall, releasing a significant amount of pollen. This species is known for its role in causing allergies, particularly in the late summer and early fall. Its pollen is a common trigger for hay fever, affecting many people. Control measures include mowing and herbicide application to reduce its spread in agricultural areas and urban settings.