Persistent Guilds

Persistent guilds contain species that develop and maintain advance regeneration. Many persistent species have large seed reserves that enable germinants to establish in shade or on dry sites. Large cohorts often develop as a result of mast seeding or other occasional events (e.g., wet years). Species with moderate understory tolerance may survive with a cycle of die back and resprouting, whereas more tolerant species maintain seedling or sapling banks. Small canopy gaps maintain the regeneration pool for these species, but individuals do not enter the overstory until more significant canopy disturbances occur. (Sutherland and others 2000)

Large-seeded, advance growth dependent 

Carya cordiformis, Carya glabra, Carya laciniosa, Carya ovata, Carya tomentosa, Quercus coccinea, Quercus palustris, Quercus rubra, Quercus velutina, Quercus alba, Quercus bicolor, Quercus macrocarpa, Quercus prinus, Quercus stellata

Oaks and hickories develop and maintain "advance growth" regeneration. New cohorts arise from established seedlings or sprouts that are released by canopy openings: Seeds germinate well in the understory, but seedlings have intermediate shade tolerance so survival under a closed canopy is limited to a few years. Seedlings actually persist as "seedling sprouts" with repeated episodes of dieback and resprouting. In spite of the large, gravity-dispersed seeds, this guild often colonizes new areas with seeds cached and forgotten by birds and rodents. Vigorous sprouts also develop from cut or damaged stems. Seedling sprouts or other sprout origin stems: exhibit fast height growth which makes this group more competitive in canopy openings than the other persistent species. Hickories and white oaks are slow-growing and more shade tolerant than red oaks. Hickory seeds germinate in the spring following a period of cold stratification unlike white oak. (Sutherland and others 2000)

Slow-growing, understory tolerant

Acer nigrum, Acer saccharum, Carpinus caroliniana, Fagus grandifolia, Ostrya virgimana, Oxydendrum arboreum, Tilia americana, Tilia heterophylla, Tsuga canadensis

This is a highly versatile group. Good seed crops are produced at regular intervals and a variety of seedbeds are suitable for germination. Seedlings grow slowly and survive in the shaded understory for many years. As small canopy gaps form, individuals are gradually recruited into the overstory. Seedling or sapling banks are common and Ostrya virginiana and Tilia spp. also maintain a seed bank. (Sutherland and others 2000)