Here is a plant that anyone with allergies should know about and what it looks like. Giant ragweed. Rather inconspicuous looking plant with rods of tiny green flowerets. Leaves are 3-5 palmated, serrated edged and fairly large. Plant is commonly 4-12 feet tall, is extremely common in fields, ditches and other waste locations, is a member of the composite (sunflower) family and has no edible uses. Blooming time is very close to the time goldenrod blooms, so many people unknowingly blame the goldenrod for their allergies!