Seedling Growth Form of Oaks

Seedling growth strategies and seed size effects in fourteen oak species native to different soil moisture habitats

“…In general, Quercus nuttallii, Q. shumardii, Q. lyrata, Q. velutina and Q. rubra grew most rapidly while Q. stellata, Q. hemisphaerica, Q. laevis, Q. margaretta and Q. falcata grew most slowly (Long 1993). Although results may have differed somewhat if plants were grown in a greater variety of environments, these findings agree with our anecdotal observations of seedling growth in natural forests, and with other oak seedling studies that have compared growth of species from different soil moisture habitats (Bourdeau 1954;Farmer 1980;Matsuda et al 1989). Slow growth of xeric species may reflect evolution of a stress tolerance strategy which enhances survival when water or nutrients are scarce, but constrains growth when soil resources are relatively abundant (Grime 1977).…”

“…In nature, allometric differences may be maintained for larger seedlings. Low rates of shoot growth relative to root growth have been found in other dry site woody species including oaks (Zimmer and Grose 1958;Immel et al 1978;Matsuda et al 1989). However, in one recent study of black spruce [Picea mariana (Mill.)…”

“…3). Other studies have reported greater hight growth of wet site versus dry site woody species, but no adjustments for differences in plant size were made (Bourdeau 1954;Farmer 1980;Matsuda et al 1989). In our study, the same trend was found even after correcting for differences in total plant weight.…”

“…Evolutionary response is reflected in the distribution of plants across natural environmental gradients. For example, plants common to dry sites tend to allocate proportionally more carbon to roots than do plants from moist sites, even when both plant types are grown in similar environmental conditions (Immel et al 1978;Bongarten and Teskey 1987;Matsuda et al 1989;Miller et al 1990). Evolved tendencies in shoot/root allometry have also been found for late versus early successional species (Monk 1966;Gleeson and Tilman 1990) and species from nutrient poor versus nutrient rich sites (Elberse and Berendse 1993).…”

“…If two taxa have very different anatomy, observed differences in allometry may simply reflect anatomical constraints on growth. To minimize problems with experimental design, investigations of plant allometry should: (1) compare plant growth in a common environment where plastic responses to environment are minimized; (2) compare plants at a common developmental state (i. e., common size) to control for ontogenetic effects; and (3) use congeneric species or conspecific varieties to reduce problems with phylogenetic constraints (Bongarten and Teskey 1987;Matsuda et al 1989;Rice and Bazzaz 1989;Garnier 1992;Elberse and Berendse 1993).…”