Red oak, or northern red oak is a medium to tall tree, reaching a potential height of approximately 60-90 feet at maturity. The trunk is broad, reaching two to three feet in diameter on the largest of trees, and may flair outward slightly at the base. The large, spreading branches form a broad crown. Red Oak will reach a height of 60 to 70 feet and a spread of 40 to 60 feet when open-grown.