BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Cardaria draba | Heart-Podded Hoary Cress 



GENERAL BOTANICAL CHARACTERISTICS : 
Heart-podded hoary cress is a rhizomatous perennial herb with numerous,
erect or ascending stems.  It grows from 8 to 20 inches (20-50 cm) tall
[16,17].  Leaves are elliptic to oblong, and 1.6 to 4 inches (4-10 cm)
long [17,30].  The fruit is an indehiscent, glabrous, heart-shaped to
oval silicle. It is 0.14 to 0.18 inch (3.5-4.5 mm) long and wide, with
two seeds [19,22,30].  Roots usually occur at depths of 29-32 inches
(74-81 cm) [22], but have penetrated to a depth of 30 feet (9 m) in the
Pacific Northwest [25].


RAUNKIAER LIFE FORM : 
   Hemicryptophyte
   Geophyte


REGENERATION PROCESSES : 
Sexual:  Heart-podded hoary cress reproduces by seed.  It is
self-incompatible and is pollinated by insects [16,22].  One plant can
produce from 1,200 to 4,800 seeds.  There is no mechanism for seed
dispersal.  Seed viability the first season may be as high as 84
percent, but can drop to 31 percent by the second year and 0 percent by
the third year [18,20].

Cotyledons appear aboveground 5 to 6 weeks after planting and grow to
maximum size in about 3 weeks.  During this period, the first leaves
emerge and form a loose rosette.  Stems arise from the center of each
rosette in late April [19,22].  

Vegetative:  Heart-podded hoary chess spreads vigorously by creeping
roots.  Lateral perennial roots spread and produce new rosettes and
flowering shoots.  One plant can eventually result in a large colony
[2,20].  Within 3 weeks of germination, a seedling root can begin
producing buds; if these are at or near the soil surface they may
produce new rosettes [18,22].  Buds borne at deeper levels may develop
as rhizomes.  In the absence of competition, one plant can produce 455
shoots the first year [18].


SITE CHARACTERISTICS : 
Heart-podded hoary cress is widespread in fields, waste places, meadows,
pastures, and along roadsides [14,16,22,30].  It also invades cropland
[9].  It is most often found in open, unshaded areas on disturbed,
generally saline soils [12,17,22], but can grow on almost any soil [25].
In Canada, heart-podded hoary cress, like other Cardaria species, may
grow better in moist than dry conditions [22].

Elevation:  Heart-podded hoary cress is found from 4,224 to 8,857 feet
(1,280-2,684 m) in Utah, 5,214 to 6,402 feet (1,580-1,940 m) in Montana,
2,310 to 3,960 feet (700-1,200 m) in Oregon, 3,500 to 8,500 feet
(1,050-2,550 m) in Colorado, and at less than 3,960 feet (1,200 m) in
California [10,11,12,18,27,35].  

 


SUCCESSIONAL STATUS : 
Facultative Seral Species

Heart-podded hoary cress invades disturbed sites and may move into
productive sites when growing conditions are ideal [12,17].  It does
best in open, unshaded areas and can replace fields of alfalfa (Medicago
sativa) if not controlled [22,25].


SEASONAL DEVELOPMENT : 
Heart-podded hoary cress flowering dates for several states are as follows:

California     Mar-June  [23]
Kansas         May-June  [2]
Illinois       Apr-June  [21]
Nebraska       May-July  [8]
Great Plains   Apr-Aug   [9]

In Oregon, heart-podded hoary cress seed matures in late July and early
August [22].  

Related categories for Species: Cardaria draba | Heart-Podded Hoary Cress