The Distribution and Life History of Trillium nivale Riddell

The snow trillium, the earliest spring flower in the woods of Iowa, is confined in its range almost entirely to the North Central States. It propagates mainly by seed but occasionally by the branching of the corn. At the Ledges State Park records show that the first flowers appear usually between the 10th and 25th of March. The seeds are mature early in June and the plants then die and disappear until the following spring. The seeds do not germinate until one or more winters have passed. The plant the first year is very delicate and consists of a corm, one root and one leaf. For a number of years, commonly six to nine, only one leaf is produced. Each year a new segment, usually larger than the preceding one, is added to the apical end of the corm and also one or more new roots are formed. The stage in which only a single leaf is produced is followed by one in which a stem bearing three leaves is formed. After a few years this stem, in addition to the three leaves, produces a flower. It commonly requires 10 to 12 years for the plants to reach the following period. The flowering period and the life of the plant are apparently indeterminate, continuing until terminated by some adverse circumstance