BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Heracleum lanatum | Cow Parsnip 



GENERAL BOTANICAL CHARACTERISTICS : 
Cow parsnip is a native, perennial forb that grows from 3.3 to 10 feet
(1-3 m) tall [24,26,35] and has broad, flat-topped umbels [33,80].  It
grows from a stout taproot or a cluster of fibrous roots [35,39,72,82].
Leaves are 8 to 20 inches (20-50 cm) long and wide [26,59,82].  The
egg-shaped fruit is 0.32 to 0.48 inch (8-12 mm) long and 0.24 to 0.36
(6-9 mm) wide [26,82].  


RAUNKIAER LIFE FORM : 
   Hemicryptophyte


REGENERATION PROCESSES : 
Cow parsnip reproduces by seed [15,38].  For successful germination in
the laboratory, seed should not be stored more than 3 years [72,73].
Some flowers within an umbel only produce stamens, while others are
hermaphroditic.  Secondary umbels develop synchronously approximately 10
to 14 days after the primary umbel.  Hermaphroditic flower and seed
production may be increased by herbivory [33].

The potential for cow parsnip to regenerate vegetatively is not clear;
Cole and Trull [9] include cow parsnip in a group of plants that
"regenerate rapidly from subsurface adventitious buds."  


SITE CHARACTERISTICS : 
Cow parsnip occurs in a variety of habitats including woodlands, forest
openings, grasslands, and riparian areas such as wet meadows, stream
terraces, alluvial benches, floodplains, and stream and lake margins
[26,28,29,82].  It is commonly found growing in snow-maintained
disclimaxes such as avalanche chutes [28,47,55].  Cow parsnip is a
facultative wetland species [29]; it grows best in moist, shaded areas
[35,59,84] but can also be found in open woodlands and clearings
[35,38,44,56,80].

Cow parsnip grows best on moist to semiwet soils with good drainage
[24,34,44,47].  It grows best on loam and sandy loam soils derived from
limestone and shale, but occurs on clay, clay loam, and gravelly
substrates as well [1531,65]. 

Elevations for cow parsnip for several states are as follows:

                         feet              meters

Arizona               7,500-9,000        2,250-2,700     [42]
California                 <8,500             <2,600     [35]
Colorado             4,700-10,500        1,410-3,150     [15,30]
Montana               4,200-8,500        1,260-2,550     [3,29]
Utah                  5,200-9,000        1,560-2,700     [15]
Washington            3,300-5,775        1,000-1,750     [2,9]
Wyoming              3,400-12,500        1,020-3,750     [15]



SUCCESSIONAL STATUS : 
Cow parsnip occurs in seral and climax communities.  It is shade
tolerant, but also grows in some open habitats [29,38,41,44,58].  Cow
parsnip is a common understory species in quaking aspen community types,
which are often successional in subalpine forests of the Intermountain
region [4,20,29,41].  Cow parsnip is a member of the red alder (Alnus
rubra) association of Oregon that may be replaced in 30 to 50 years by
black cottonwood or in 30 to 70 years by grand fir (Abies grandis) [31].
The red-osier dogwood-cow parsnip community type of Utah and
southeastern Idaho is an early seral type that colonizes streambanks and
adjacent areas [60].  In the black hawthorn-cow parsnip habitat type of
Washington, cow parsnip can grow as well with or without the black
hawthorn canopy [13].  Cow parsnip occurs in climax aspen forests
throughout the Intermountain West, and in mature to climax subalpine
forests in Wyoming and Montana [14,41,58].

Studies of cow parsnip in clearcuts indicates that its response to
canopy removal is variable.  In northern Utah cow parsnip cover was
variable in both control and clearcut stands.  Early succession
following a 1974 clearcut of aspen communities (with no slash treatment)
in northern Utah was studied.  Percent understory cover of cow parsnip
on clearcuts and uncut controls was [4]:

        1973             1975             1976             1977   
     cut  control     cut  control     cut  control     cut  control

      0     1.5       1.8     0        0.7    0.3       0.4    0.4
      
The effects of clearcutting on wildlife habitat were studied in a moist
subalpine forest in central Colorado.  Understory cover of cow parsnip
before and after clearcutting (with no slash treatment) was [12]:

         before logging               years after logging (1978-1982)
            (1976)                       1     2     3     4     5

cover(%)      0.6                       3.1   8.2   8.9  13.3  10.7

In the subalpine fir/queencup beadlily habitat type in northwestern
Montana, cow parsnip occurs in a variety of disturbed and undisturbed
communities.  Relative frequency and average canopy cover of cow parsnip
were as follows [87]:  

                                           relative frequency    % cover

wildfire (35-70 years prior to study)               6              15
clearcut (15-35 years old), slash dozer-piled       4               3
clearcut (15-35 years old), slash not dozer-piled   8              15    
old-growth (two types of plots)                     3,20          0.5,7.8

Snowchutes are "topographic climax" or disclimax communities that
produce an abundance of grizzly bear foods.  In subalpine fir/menziesia,
subalpine fir/queencup beadlily, and subalpine fir/smooth woodrush
habitat types, relative frequency/average precent canopy cover of cow
parsnip in snowchutes was 50/19, 65/13, and 75/6.2, respectively [87].


SEASONAL DEVELOPMENT : 
Cow parsnip flowering dates are as follows:

Arizona             July-Aug       [42]
California          Apr-July       [59]
Colorado            May-Aug        [15]
Georgia             May-Aug        [63,83]
Kentucky            May-Aug        [63,83]
North Carolina      May-Aug        [63,83]
North Dakota        Jun-Aug        [15]
Tennessee           May-Aug        [63,83]
Utah                Jun-Aug        [15]
Virginia            May-Aug        [63,83]
West Virginia       May-Aug        [63,83]
Wyoming             Jun-July       [15]
Great Plains        May-July       [26]

Related categories for Species: Heracleum lanatum | Cow Parsnip