The Formation of Hypertrophied Lenticels, Adventitious Water Roots, and an Oxidized Rhizosphere by Acer rubrum Seedings over TIme Along a Hydrologic Gradient

Kirk J. Havens, Virginia Institute of Marine Science

Abstract

The effect of three hydrologic regimes (dry, saturated, and inundated) on red maple (Acer rubrum) seedlings was investigated both in the laboratory and in the field. Hypertrophied lenticel formation occurred within 7 days in the inundated site. Adventitious water root formation was observed after 3 weeks in the inundated site but only after 12 weeks in the saturated site. Hypertrophied lenticels and adventitious water roots were lacking in the seedlings grown in the dry site. Hydrophytic vegetation was shown to elevate the redox potential in the upper 15 centimeters of the soil profile and the ability of red maple seedlings to oxidize their rhizosphere was demonstrated using a leuco-methylene blue/agar medium. The visible presence of ferric iron deposits along the rhizoplane of red maple seedlings was observed after 3 weeks of inundation. Ferric iron deposits were not observed in the dry seedlings and were only observed in the saturated seedlings after the area was flooded for 6 weeks.