Magnolia L. (magnolia)
Plants small to medium-sized
trees. Terminal buds to 3 cm long, prominent. Leaves short-petiolate. Leaf
blades longer than wide, unlobed, lacking teeth or sometimes with a pair of
small points or spreading teeth above the middle, the tip narrowed or tapered
to a point. Fruits conelike aggregates of follicles, dehiscing at maturity to
release the seeds, which remain attached for some time, hanging by thin threads
of tissue. Seeds relatively large, with a brightly colored aril covering the
surface. About 120 species, North America south to Venezuela, Asia, Malaysia,
south to Indonesia.
Magnolias
generally are considered to be pollinated by beetles (Heiser, 1962), although a
number of other types of insects visit the flowers.
Several species
of Magnolia are cultivated in Missouri in addition to those treated
here, but thus far none has become established outside cultivation. In addition
to the two species included below, M. macrophylla Michx. (bigleaf
magnolia, umbrella tree) should be searched for in southeastern Missouri. It occurs
natively at a disjunct station on Crowley’s Ridge in notheastern Clay County,
Arkansas, less than ten miles from the Missouri border, where a small remnant
population persists in the mesic upland forest of a drainage (Figlar, 1981).
This species differs in its leaf blades with cordate bases and larger flowers
(tepals 12–18 cm long).