Hurricane damage influences foliar polyphenolics and subsequent herbivory on surviving trees

Hurricane damage results in tree mortality and variation in both light and nutrient availability for the individuals that remain. In turn, resource av ailability influences the interactions between plants and insect herbivores . We report effects of Hurricane Opal on the phenolic chemistry and levels of defoliation on surviving trees at the Coweeta Hydrologic Laboratory in N orth Carolina. We measured foliar astringency, hydrolysable tannins, and co ndensed tannins in the foliage of red maple and red oak saplings in hurrica ne-damaged and undamaged sites. We estimated inorganic nitrogen and phospho rus availability in the soil, and the accumulated leaf area removed by inse ct herbivores. The foliar astringency of both red maple and red oak was hig her in sires damaged by the hurricane. Later in the growing season, condens ed tannin levels were significantly higher in the foliage of red oak in dam aged sites. There were no consistent differences in ammonium, nitrate, or p hosphate availability between damaged and undamaged sites. Despite higher f oliar astringency of trees in sites damaged by Hurricane Opal, levels of de foliation by insect herbivores were higher in damaged than in control sites on both tree species. Apparent increases in putative defensive compounds f ollowing hurricane damage did not protect trees from herbivory.