BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Kochia scoparia | Summer-Cypress 



GENERAL BOTANICAL CHARACTERISTICS : 
Summer-cypress is an introduced, annual forb that grows from 1 to 6 feet
(0.3-1.8 m) tall [9,27,98].  Stems are erect, simple to much-branched,
and often form pyramidal or rounded tops [6,35,37,39].  Leaves are 0.8
to 4 inches (2-10 cm) long and 0.02 to 0.48 inch (0.5-12 mm) wide
[35,39,98].  The dry fruit has a single seed from 0.08 to 0.12 inch (2-3
mm) long [17,35].  Roots generally penetrate to depths of 6 to 8 feet
(1.8-2.4 m) [9,26,27,32], but reached depths of 16 feet (4.8 m) in a
sorghum field in Kansas during a severe drought [100].  Roots can extend
laterally up to 22 feet (6.6 m) [9,27].  Summer-cypress is drought
tolerant [27,46,58].  It is not tolerant of spring flooding [51].


RAUNKIAER LIFE FORM : 
   Therophyte


REGENERATION PROCESSES : 
Summer-cypress reproduces exclusively by seed.  It exhibits extreme
reproductive plasticity in that one plant can produce over 50,000 seeds
per year under favorable conditions, but only 5 seeds per year under
stressful conditions [9,44].  Typically a summer-cypress plant will
produce about 14,600 seeds per year [27].  Major means of seed
dissemination is a "tumbleweed" dispersal mechanism via stem abscission
[4,9,43,44].  Wind and water are effective dispersal agents as well
[45].  Seeds of summer-cypress have a dormancy period of 2 to 3 months
and germinate early in the spring [27,30,45].  Seeds germinate in
temperatures ranging from 39 to 106 degrees Fahrenheit (3.9-41 deg C),
with optimum germination occurring at 61 degrees Fahrenheit (16 deg C)
[27].  Seeds have little or no seedbank viability [44]; they either
germinate or decay in 1 year [9].  In eastern Washington and Oregon
summer-cypress seeds buried 4 inches (10 cm) in soil had less than one
percent viability after 2 years [9,27].  Seed viability is reduced by
livestock digestion [8,9].  Seedlings of summer-cypress are
frost tolerant [9,27,44].
  


SITE CHARACTERISTICS : 
Summer-cypress is common in fields, pastures, rangelands, waste places,
and along roadsides [6,30,35,41,89].  Summer-cypress is most often found
in open, unshaded areas on disturbed sites [9,17,46,55,90].  It grows
well on a variety of soil types [46,55], and is often found on
saline/alkaline soils [89,90].  

Elevations for summer-cypress are as follows:

                        feet               meters

California                <5,000              <1,500      [39]
Colorado             4,000-9,700         1,200-2,910      [24,38]
Montana                   <4,000              <1,200      [50]
New Mexico           6,200-7,000         1,860-2,100      [41,68]
Utah                 2,800-6,550           850-1,985      [24,96]
Wyoming              3,600-6,200         1,080-1,860      [24]



SUCCESSIONAL STATUS : 
Summer-cypress invades disturbed sites and may move onto undisturbed
sites when growing conditions are ideal [18,56,59,78].  It colonizes
rapidly and may suppress other vegetation [56].  Summer-cypress often
invades saline rangelands [78,90].

Summer-cypress is an early pioneering annual on denuded
areas.  On a disturbed mixed-grass prairie
site in Wyioming, summer-cypress was one of six forbs to dominate vegetation in the
first few years after disturbance; summer-cypress persisted on the site
for over 10 years [71].  In the Northern Great Plains summer-cypress
invades wetland basins during drought and is especially opportunistic
around brackish or saline wetlands [56].  In Montana summer-cypress
often forms dense single-species stands; on recently disturbed sites
other introduced annuals are common associates [37].

In Colorado summer-cypress is an early seral forb on disturbed sites and
can dominate vegetation for the first 2 years on sites that are
disturbed; if nitrogen is added, summer-cypress may dominate for up to 5
years [60].  On the Arkansas River, Colorado, in mature (20-25 year-old)
saltcedar stands, summer-cypress cover in the forb layer is nearly 100
percent [57].

Near the Great Salt Lake, Utah, die-back of shadscale has favored
summer-cypress and other species; summer-cypress is especially prevalent
in valley bottoms [25].


SEASONAL DEVELOPMENT : 
Summer-cypress flowering dates are as follows:

California            Aug-Oct          [64]
Colorado              Jun-Oct          [24]
Illinois              July-Sep         [62]
Kansas                July-Oct          [6]
Montana               Jul-Aug          24]
New England           Sep-Oct          [73]
North Dakota          July-Sep         [24]
Utah                  July-Oct         [98]
Virginia              Jun-Sep          [99]
Wyoming               July-Oct         [98]
Great Plains          July-Oct         [35]

In Idaho, Oregon, and Washington, summer-cypress flowers from July to
the first killing frost [9].
          

Related categories for Species: Kochia scoparia | Summer-Cypress