BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Scirpus validus | Soft-Stem Bulrush 



GENERAL BOTANICAL CHARACTERISTICS : 
Soft-stem bulrush is a tall, leafless marsh plant 1.5 to 9 feet (0.5-3
m) high and 0.12 to 0.8 inches (0.3-2 cm) thick with scaly, stout,
horizontal rhizomes [11].  The stems are obscurely three-sided and
spongy [17].  Spikes occur near the stem tips in branched clusters [8].
The fruit is an achene [11].


RAUNKIAER LIFE FORM : 
   Geophyte


REGENERATION PROCESSES : 
Soft-stem bulrush reproduces by both rhizomes and seeds [11,17].  It
reproduces well from seed stored in the seedbank [18].  Soil-stored
seed can remain viable for as long as 20 years [31].  In the lab, seed
viability in dry storage is more than 2 years [14].


SITE CHARACTERISTICS : 
Soft-stem bulrush grows in marshes, along lake and stream shores, and in
wet meadows.  It grows in fresh or brackish water [5,16,23].  Soils are
usually poorly-drained [5], or continually saturated [12].  Soft-stem
bulrush grows in silty or peaty soils [18].  Under greenhouse conditions
soft-stem bulrush produced more aboveground biomass in silty clay soils
than in clay or sand alone [1].  Belowground biomass was equal in silty
clays and clays, and lower in sandy soils.  Soft-stem bulrush seems to
grow better in saline conditions than in fresh water, and it tolerates a
wide range of salinity [32].




SUCCESSIONAL STATUS : 
Facultative Seral Species

Soft-stem bulrush is a perennial [17] and is a dominant emergent in the
northern plains and prairie states [19].  It is replaced by cattail
(Typha spp.) in continuously flooded marshes following drawdown [18].
Soft-stem bulrush is found in the third sere of succession in Wisconsin
marshes, preceded by submerged and floating plant stages and followed by
sedge meadows, shrubs, and trees [12].


SEASONAL DEVELOPMENT : 
Because of the wide distribution of soft-stem bulrush, its growing
seasons varies with latitude.  In the northeast soft-stem bulrush
flowers from July through August [23].  Flowering lasts from 5 to 6
months in wetland prairies of Nebraska [28].  Fernald [11] reported
fruits generally ripening from June through September.

Related categories for Species: Scirpus validus | Soft-Stem Bulrush