Basic Oak-Hickory Forests are the dominant plant community type at RMNA, covering about 70% of the landscape. It covers all upland and lowland areas except where landscape or soil anomalies exist. In the deep ravines the conditions allow for a transition to Basic Mesic Forest development (a distinction made evident by greater species richness and preponderance of nutrient-demanding plants). Often times this transition is intermediate, landing somewhere between the two degrees of richness. In other areas, and especially on ridge tops and northwest facing slopes, soil conditions deviate to dry and nutrient poor. In these areas the Basic Oak-Hickory Forest is supplanted by Acidic Oak-Hickory Forests and Heaths. In areas where levels of base cations are still high, but the landscape is dominated by bedrock boulders or outcrops, the Basic Oak-Hickory forest grades toward Basic Woodland plant communities with increased amounts of species such as Hickory, Ash, Redbud, Hackberry, and Cedar.