Late goldenrod

Solidago altissima is one to two meters (40-80 inches) tall, with fine hairs on the stem. The leaves are located along the stem, not in a rosette near the ground. One plant can produce as many as 1500 small yellow flower heads in a large conical array.
Solidago altissima is self-incompatible, meaning that the pollen from one plant cannot pollinate the female flower parts of the same plant.