Structural Attributes of Schizachyrium scoparium in Restored Texas Blackland Prairies

Structural attributes of the C₄, perennial bunchgrass Schizachyrium scoparium in restored prairies may be affected by the time since restoration. One hundred plants each in 8‐, 17‐, and 23‐year‐old restored prairies and a native Texas Blackland prairie were assessed for the presence/absence and diameter of a hollow crown (i.e., dead center portion), degree of fragmentation, plant height, and tiller density. Structural attributes of S. scoparium plants were generally (1) different between recent (8 years) and older (17 and 23 years) restored prairies (2) similar between the 17‐ and 23‐year‐old restored prairies, and (3) more similar between the 8‐ and 17‐year restored prairies and the native, remnant prairie than between the 23‐year restored prairie and the native prairie. Plants were shorter in restored prairies, regardless of time since restoration, than in the native prairie. Mean basal area of plants was 80–163% greater in the 17‐ and 23‐year restored prairies compared with the native and 8‐year restored prairies. Percentage of hollow crowns and fragmentation was smallest in the 8‐year restored prairie, largest in the 17‐ and 23‐year restored prairies, and intermediate in the native prairie. Tiller density exhibited inverse second‐order polynomial decreases with increasing plant basal area for all prairies. In contrast to tiller density, diameter of hollow crowns increased logarithmically with increasing plant basal area. Structural attributes of S. scoparium in restored prairies changed predictably with age, despite growing in different communities.