BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Geocaulon lividum | Northern Comandra 



GENERAL BOTANICAL CHARACTERISTICS : 
Northern comandra is a perennial, hemiparasitic forb.  It has creeping
rhizomes, located in the humus layer of the soil.  The leafy stems are 4
to 12 inches (10-30 cm) tall.  The inflorescence is a cymule with two to
three green or purple flowers.  The central flower is perfect, but the
others have stamens only.  The fruit is a one-seeded, orange drupe
[9,13,28,35,36].

Northern comandra is a root parasite that forms haustoria (lateral
outgrowths of the root) which connect it to a host's roots or rhizomes.
The haustoria are white when young but become brown with age.  They have
been described in detail.  Some host genera include spruce (Picea spp.),
pine (Pinus spp.), birch (Betula spp.), willow (Salix spp.), alder
(Alnus spp.), and twinflower (Linnaea spp.).  A more complete list of
host genera is available [36].

Northern comandra is difficult to distinguish from low sweet
blueberry (Vaccinium angustifolium) varieties, and from bog blueberry
(V.  uliginosum var. alpinum) [29].  It also closely resembles bastard
toadflax (Comandra umbellata) [40].


RAUNKIAER LIFE FORM : 
   Hemicryptophyte
   Geophyte


REGENERATION PROCESSES : 
Northern comandra presumably reproduces by seed and sprouting from
rhizomes.  However, specific information on regeneration is not
available in the literature.  Zasada [39] stated that undisturbed
feathermoss mats may inhibit germination of northern comandra seeds, but
not vegetative reproduction.


SITE CHARACTERISTICS : 
Northern comandra is found in bogs and moist coniferous or deciduous
woods [6,13,20,28].  It often occupies acid or sterile soils and damp
sands [26].  In British Columbia, northern comandra is an indicator of
continental boreal and cool temperate climates and nitrogen-poor soils.
It is found in montane to subalpine coniferous forests [17].  In New
England, northern comandra is found from sea level to 4,100 feet (1,200
m) elevation [15,29,40].  Populations in Montana are found in moist
spruce (Picea spp.) forests, often bordering wetland areas, from 3,000
to 3,300 feet (900-1,000 m) elevation [20].


SUCCESSIONAL STATUS : 
Facultative Seral Species

Northern comandra is found in both open and closed, mature white spruce
and black spruce forests in Alaska that range in age from 70 to over 180
years [4,21,25].

Northern comandra often occupies bottomland spruce-hardwood forests on
floodplains of the taiga of Alaska.  It is found in balsam poplar
(Populus balsamifera) and black cottonwood (P. trichocarpa) stands with
thick shrub understories that follow the initial shrub (alder and
willow) stage after flooding.  These stands are usually present for 20
to 100 years and are then replaced by white spruce if subsequent
flooding has not occurred.  Northern comandra persists through the
spruce stage and can be found in closed white spruce stands with a thick
feathermoss mat.  Greatest cover is reached in later successional stages
such as in open white spruce stands (250+ years old), and in black
spruce stands on older terraces above the active floodplain [23,34].


SEASONAL DEVELOPMENT : 
Northern comandra flowers from May to August [9,13,28].

Related categories for Species: Geocaulon lividum | Northern Comandra