RHODORA, Vol. 117, No. 969, pp. 1–40, 2015 E Copyright 2015 by the New England Botanical Club doi: 10.3119/14-07; first published on-line March 11, 2015. VASCULAR FLORA AND GEOECOLOGY OF MONT DE LA TABLE, GASPE´ SIE, QUE´ BEC SCOTT W. BAILEY USDA Forest Service, 234 Mirror Lake Road, North Woodstock, NH 03262 e-mail:
[email protected] JOANN HOY 21 Steam Mill Road, Auburn, NH 03032 CHARLES V. COGBILL 82 Walker Lane, Plainfield, VT 05667 ABSTRACT. The influence of substrate lithology on the distribution of many vascular and nonvascular plants has long been recognized, especially in alpine, subalpine, and other rocky habitats. In particular, plants have been classified as dependent on high-calcium substrates (i.e., calcicoles) based on common restriction to habitats developed in calcareous rocks, such as limestone and marble. In a classic 1907 paper on the influence of substrate on plants, M. L. Fernald singled out a particular meadow on Mont de la Table in the Chic-Choc Mountains of Que´bec for its unusual co-occurrence of strict calcicole and calcifuge (i.e., acidophile) plant taxa. We re-located this site, investigated substrate factors responsible for its unusual plant diversity, and documented current plant distributions. No calcareous rocks were found on site. However, inclusions of calcareous rocks were found farther up the mountain. The highest pH and dissolved calcium concentrations in surface waters were found in a series of springs that deliver groundwater, presumably influenced by calcareous rocks up the slope. Within the habitat delineated by common occurrences of calcicole species, available soil calcium varied by a factor of five and soil pH varied by almost 1.5 units, depending on microtopography and relative connection with groundwater.