|
Wildlife, Animals, and Plants
|
|
Introductory
SPECIES: Sonchus arvensis | Perennial Sowthistle
ABBREVIATION :
SONARV
SYNONYMS :
Sonchus uliginosus Bieb. [11,32]
SCS PLANT CODE :
SOAR2
SOARA2
SOARU
COMMON NAMES :
perennial sowthistle
field sowthistle
TAXONOMY :
The currently accepted scientific name for perennial sowthistle is
Sonchus arvensis L. (Asteraceae) [11,13,15,19]. The following two
subspecies are recognized by some authors and are used in this writeup
[13,19]:
S. a. ssp. arvensis
S. a. ssp. uliginosus (Bieb.) Nyman
Other authors [11,20] recognize two varieties, Sonchus arvensis var.
arvensis and S. a. var. glabrescens (Guenther) Grab & Wimmer, which is
synonomous with S. a. ssp. uliginosus.
LIFE FORM :
Forb
FEDERAL LEGAL STATUS :
No special status
OTHER STATUS :
NO-ENTRY
COMPILED BY AND DATE :
Jennifer H. Carey, January 1995
LAST REVISED BY AND DATE :
NO-ENTRY
AUTHORSHIP AND CITATION :
Carey, Jennifer H. 1995. Sonchus arvensis. In: Remainder of Citation
DISTRIBUTION AND OCCURRENCE
SPECIES: Sonchus arvensis | Perennial Sowthistle
GENERAL DISTRIBUTION :
Perennial sowthistle, native to Europe and Asia, was introduced into
temperate North America as early as 1814 [20]. It is naturalized across
most of the northern United States and Canada. It occurs from Nova
Scotia and Newfoundland west through all Canadian provinces and
territories to Alaska, south to southern California, east through the
central Great Plains to North Carolina, and north throughout New England
[11,13,15,20]. Although most southeastern United States floras
[5,12,32,48] indicate that perennial sowthistle does not occur south of
North Carolina, it is listed as occurring in Gulf Island National
Seashore in the Florida panhandle [44].
ECOSYSTEMS :
FRES10 White - red - jack pine
FRES11 Spruce - fir
FRES13 Loblolly - shortleaf pine
FRES14 Oak - pine
FRES15 Oak - hickory
FRES16 Oak - gum - cypress
FRES17 Elm - ash - cottonwood
FRES18 Maple - beech - birch
FRES19 Aspen - birch
FRES20 Douglas-fir
FRES21 Ponderosa pine
FRES22 Western white pine
FRES23 Fir - spruce
FRES24 Hemlock - Sitka spruce
FRES25 Larch
FRES26 Lodgepole pine
FRES27 Redwood
FRES28 Western hardwoods
FRES29 Sagebrush
FRES36 Mountain grasslands
FRES37 Mountain meadows
FRES38 Plains grasslands
FRES39 Prairie
FRES41 Wet grasslands
FRES42 Annual grasslands
FRES44 Alpine
STATES :
AK CA CO CT DE FL ID IL IN IA
KS KY ME MD MA MI MN MO MT NE
NV NH NJ NY NC ND OH OR PA RI
SD UT VT VA WA WV WI WY DC AB
BC MB NB NF NT NS ON PE PQ SK
YT
ADMINISTRATIVE UNITS :
ACAD CUVA DEWA DINO EFMO GATE
GLAC GUIS ISRO NERI NOCA OLYM
PIPE REDW ROCR ROMO THRO VOYA
WICA
BLM PHYSIOGRAPHIC REGIONS :
1 Northern Pacific Border
2 Cascade Mountains
3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
6 Upper Basin and Range
8 Northern Rocky Mountains
9 Middle Rocky Mountains
10 Wyoming Basin
11 Southern Rocky Mountains
12 Colorado Plateau
13 Rocky Mountain Piedmont
14 Great Plains
15 Black Hills Uplift
16 Upper Missouri Basin and Broken Lands
KUCHLER PLANT ASSOCIATIONS :
NO-ENTRY
SAF COVER TYPES :
NO-ENTRY
SRM (RANGELAND) COVER TYPES :
NO-ENTRY
HABITAT TYPES AND PLANT COMMUNITIES :
Perennial sowthistle frequently occurs in fields and meadows. It was
present in the following six community types in North Dakota: prairie
cordgrass (Spartina pectinata), foxtail barley (Critesion jubatum),
saltgrass (Distichlis spicata), mat muhly (Muhlenbergia richardsonis),
little bluestem (Schizachyrium scoparium), and Canada bluegrass (Poa
compressa)-Kentucky bluegrass (P. pratense) [34].
Perennial sowthistle occurs in dry meadows of whitetop (Scolochloa
festucacea) with alkali rayless aster (Brachyactis ciliata var. angusta)
in the Delta Marsh in south-central Manitoba [46].
Plants associated with subspecies uliginosus in halophytic or
semihalophytic communities in Saskatchewan include western yarrow
(Achillea lanulosa), rosy pussytoes (Antennaria microphylla), heath
aster (Aster ericoides), American licorice (Glycyrrhiza lepidota),
Dyersweed goldenrod (Solidago nemoralis), saltgrass, foxtail barley, and
mat muhly [20].
In southern Quebec, perennial sowthistle colonizes riverbanks with
silverweed cinquefoil (Argentina anserina) and white sweetclover
(Melilotus alba) [26].
VALUE AND USE
SPECIES: Sonchus arvensis | Perennial Sowthistle
WOOD PRODUCTS VALUE :
NO-ENTRY
IMPORTANCE TO LIVESTOCK AND WILDLIFE :
Perennial sowthistle is good feed for foraging animals such as rabbits.
It is also acceptable as a livestock feed, although not highly preferred [20].
PALATABILITY :
Perennial sowthistle palatability is rated as poor to fair for cattle,
sheep, and horses [6]. Perennial sowthistle is relatively unpalatable
to lambs. Grazing lambs rejected it 70 to 80 percent of the time when
offered a choice [22].
NUTRITIONAL VALUE :
Perennial sowthistle has a nutritive value equal to or superior to that
of alfalfa (Medicago sativa). Crude protein, macro and micronutrients,
in vitro digestible dry matter, and herbage neutral detergent fiber
concentration are listed for perennial sowthistle at three growth
stages: vegetative, late bud, and mid-bloom [22].
COVER VALUE :
Perennial sowthistle is generally rated as poor to fair cover for
wildlife, but is listed as good cover for mule deer and white-tailed
deer in North Dakota [6].
VALUE FOR REHABILITATION OF DISTURBED SITES :
NO-ENTRY
OTHER USES AND VALUES :
Perennial sowthistle leaves are edible [6,8], and the roots have been
roasted and used as a substitute for coffee [20].
MANAGEMENT CONSIDERATIONS :
Perennial sowthistle is a noxious weed in 28 states [25] and in Canada
[20]. It infests cultivated cropland, lawns, disturbed areas, meadows,
and pasture [20]. Perennial sowthistle is unlikely to become a noxious
weed in the southern United States because it is not tolerant of hot
climates [49].
Perennial sowthistle continues to spread into less inhabited regions of
Canada, but its expansion may be limited by cold climate. During a 1986
to 1988 study, perennial sowthistle was recorded for the first time in
Wood Buffalo National Park on the border of the Northwest Territories
and Alberta. It was found at 9 of 18 sites. Wein and others [47] fear
it will continue to spread into wetland vegetation that is stressed by
lower peak water flows which have occurred since the Peace River was
dammed in 1968.
Sonchus arvensis ssp. uliginosus was listed as "persistent" in northern
Manitoba. It was present at low numbers on less than 5 of 42 sites in
1989. It had a similar abundance and distribution in 1959. The cold
climate may be preventing reproduction but regular seed input from other
areas may be perpetuating the species [38].
Herbicide application techniques and perennial sowthistle susceptibility
are described [4,20,43].
Two gall-forming flies native to Europe are being studied as potential
biological controls for perennial sowthistle. Tephritis dilacerata
forms galls on the flowerheads and prevents seed production. This fly
was released in Canada in 1979 and in successive years but has not yet
successfully overwintered. Cystiphora sonchi, which forms leaf galls,
was first released in 1981 in Canada and is surviving and reproducing.
Its overall impact on perennial sowthistle in North America is not yet
known [30,31,37].
BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Sonchus arvensis | Perennial Sowthistle
GENERAL BOTANICAL CHARACTERISTICS :
Perennial sowthistle is an introduced, perennial, deep-rooted forb. The
erect, hollow stems grow 1 to 6 feet (0.3-1.8 m) tall and contain a
milky fluid [20]. Inflorescences have several to many flowerheads
[19]. The achene has a mostly persistent pappus which is four times
longer than the achene. The pappus hairs have hooked cells which aid in
animal dispersal [20].
Perennial sowthistle either has rhizomes or creeping roots with buds.
The literature has not discriminated between these two types of
vegetative reproductive organs. This report uses the term rhizomes but
recognizes the possibility that the underground vegetative buds may
originate from root tissue and not stem tissue.
The extensive creeping rhizomes, 0.1 to 0.2 inch (0.25-0.5 cm) in
diameter, originate from short, spindle-shaped, somewhat branched
primary roots. These rhizomes are generally 2 to 5 inches (5-12 cm)
deep, but perennial sowthistle can produce vegetative buds 20 inches (50
cm) below the ground surface. Vertical roots penetrate 6 feet (2 m)
deep [20].
RAUNKIAER LIFE FORM :
Hemicryptophyte
REGENERATION PROCESSES :
Perennial sowthistle reproduces vegetatively and by seed.
Perennial sowthistle typically produces an average of 30 seeds per
flowerhead. The main stalk of a perennial sowthistle in North Dakota
produced 62 flowerheads and 9,750 well-developed seeds. However, large
clones often do not produce many seeds because of self-incompatability.
Viability of perennial sowthistle seeds is generally high (70-90%) [20].
Seed dispersal is primarily by wind, but hooked cells on pappus hairs
also cling to clothes and animal fur [20]. Sheldon and Burrows [36]
computed maximum dispersal distances for perennial sowthistle based on
the rate of fall of achenes in still air. Assuming a mean plant height
of 35 inches (90 cm) and a vertical convection speed of 6.8 miles per
hour (10 km/hr), perennial sowthistle achenes are dispersed the
following distances at each wind speed [36]:
Wind Speed Dispersal Distance
miles per hour (km/hr) feet (m)
3.4 (5.5) 11 (3.3)
6.8 (10.9) 22 (6.7)
10.3 (16.4) 33 (10.0)
Buried perennial sowthistle seeds persist an undetermined length of time
in the seedbank [28,45]. In the Delta Marsh, Manitoba, there was an
average of 3.4 perennial sowthistle seeds per square foot (38/sq m) in
the hybrid cattail (Typha X glauca) zone and 2.3 per square foot (25/sq
m) in the common reed (Phragmites australis) zone [28].
Seed germination occurs when soils are warm. Air temperatures ranging
from 77 to 86 degrees Fahrenheit (25-30 deg C) are optimal for
germination [20]. Hogenbirk and Wein [17] studied the emergence of
seedlings from soil seedbanks at different temperatures. Seeds were
collected from a 13.2 square inch (85 sq cm), 4 inch (10 cm) deep sample
in a willow (Salix spp.) savanna on the Peace-Athabasca Delta in
Alberta. Eight and seven perennial sowthistle seedlings emerged at
day/night air temperatures of 68/50 degrees Fahrenheit (20/10 deg C) and
86/59 degrees Fahrenheit (30/15 deg C), respectively [17].
Light stimulates germination. The rate of emergence decreases rapidly
at soil depths greater than 0.2 inch (0.5 cm) [20].
Perennial sowthistle seeds do not germinate under submerged conditions
but germinate readily when the soil surface is exposed [28,45].
Perennial sowthistle seeds germinated under simulated drawdown
conditions in 17 percent of substrate samples collected at Delta Marsh,
Manitoba [28]. Perennial sowthistle established on artificially exposed
mudflats on Delta Marsh at low densities (less than 1 seedling per
square foot [<10/sq m]) [23]. Perennial sowthistle was present on a
site in northwestern Minnesota 2 years after artificial drawdown in a
common cattail (Typha latifolia) and narrowleaf cattail (T.
angustifolia) community [14].
Seedlings survive best where soil is moist. Perennial sowthistle forms
a rosette early in its development. Flowering stems develop when plants
have 12 to 15 leaves, usually during the second growing season [20].
Perennial sowthistle colonizes a site rapidly by vegetative
reproduction. The rate of vegetative spread from the border of a
perennial sowthistle clone in North Dakota varied from 1.6 to 9.2 feet
per year (0.5-2.8 m/yr). Perennial sowthistle persists in cultivated
fields because new plants can develop from rhizome sections less than 1
inch (2.5 cm) long if buds are present [20].
Vegetative and reproductive growth is enhanced by full light, moderate
temperatures, and water-saturated soil. Growth is more rapid at
day/night temperatures of 68/59 degrees Fahrenheit (20/15 deg C) than at
either 86/77 degrees Fahrenheit (30/25 deg C) or 50/41 degrees
Fahrenheit (10/5 deg C) [49].
SITE CHARACTERISTICS :
Perennial sowthistle occurs along roads, marsh edges, lakeshores, and
riverbanks, and in cultivated fields, meadows, and pastures. Although
considered an upland species, perennial sowthistle grows well on moist
sites. In a North Dakota grassland, perennial sowthistle occurs in the
intermediate moisture zone. It does not occur in locations which are
permanently flooded nor where drainage is excessive [7]. Perennial
sowthistle is present at low frequencies in the emergent zone of oxbow
lakes in the Athabasca River drainage in Alberta [21].
Perennial sowthistle is most competitive on sites with poorly drained
soils, high water-holding capacities, and moderate alkalinity [49]. It
does well on light, well-drained soil if there is a good supply of
moisture. In southern Quebec, perennial sowthistle colonized low angle,
sandy riverbanks with 0.4 percent organic matter and less than 25
percent vegetative cover [34]. Perennial sowthistle commonly occurs on
saline soils [34,41]. It was encountered in 29 percent of inventoried
saline sites in the Canadian Prairie Provinces [3].
Extremely cold climates may limit perennial sowthistle expansion. Seeds
and rhizomes had not developed on perennial sowthistle observed in
August in northern Manitoba. The conditions required to reduce the
survival of perennial sowthistle roots and perennating buds by 50
percent is 1 degree Fahrenheit (-17 deg C) for 2 hours [35].
SUCCESSIONAL STATUS :
Perennial sowthistle is an early successional species [20]. It is not
reported to occur under forest canopies and thus may be intolerant of
shade.
Perennial sowthistle rapidly colonizes disturbed sites [20] as well as
recently exposed mud flats [14,23,45]. Drought was simulated in a
wetland community on the Peace-Athabasca Delta, Alberta, by
transplanting soil blocks upslope. Average perennial sowthistle cover
increased from 2 to 10 percent in 1 year, possibly in response to
decreased height growth of bluejoint reedgrass (Calamagrostis
canadensis) [16]. Flooding eventually eliminates perennial sowthistle
from mud flats [45].
SEASONAL DEVELOPMENT :
Perennial sowthistle begins to flower around July 1 in the northern
United States and continues until frost, although flowering is mostly
complete by late summer. Fruits mature about 10 days after flowering.
Seedlings do not emerge until mid- to late May in the Great Plains of
the United States and in Saskatchewan. Shoots and new roots and
rhizomes begin to develop when the soil warms, usually in late April.
New shoots develop until late summer [20].
FIRE ECOLOGY
SPECIES: Sonchus arvensis | Perennial Sowthistle
FIRE ECOLOGY OR ADAPTATIONS :
Perennial sowthistle populations probably resist fire because buried
seeds and vegetative buds on rhizomes are protected from fire by soil.
Perennial sowthistle may expand its range with rapid dispersal of seeds
onto recently burned sites. However, if fire enhances growth of native
vegetation which competes with perennial sowthistle, perennial
sowthistle may decrease after fire.
POSTFIRE REGENERATION STRATEGY :
Rhizomatous herb, rhizome in soil
Ground residual colonizer (on-site, initial community)
Initial-offsite colonizer (off-site, initial community)
FIRE EFFECTS
SPECIES: Sonchus arvensis | Perennial Sowthistle
IMMEDIATE FIRE EFFECT ON PLANT :
Fire probably top-kills perennial sowthistle. Buried seed and
perennating buds on rhizomes probably remain undamaged by most fires.
DISCUSSION AND QUALIFICATION OF FIRE EFFECT :
NO-ENTRY
PLANT RESPONSE TO FIRE :
Perennial sowthistle response to fire is variable. Perennial sowthistle
cover and frequency may increase, decrease, or remain the same after
fire in grasslands [24,27]. Fire in wetlands may increase perennial
sowthistle cover [16,40].
Perennial sowthistle occurred as a minor species on five mixed grassland
study sites within the Tewaukon National Wildlife Refuge in North
Dakota. Prescribed fires were conducted in late spring and the
vegetation was sampled in postfire year 2. Two sites had no significant
difference (p=0.05) in perennial sowthistle canopy cover between burned
areas and an unburned control, two sites had higher canopy cover on the
unburned controls, and one site had higher canopy cover on the burned
area [27].
In a northwestern Iowa prairie, perennial sowthistle frequency 1 year
after an early April fire was higher than prior to burning. For two
sites, perennial sowthistle prefire frequency was 8.1 and 18.9 percent
and postfire frequency was 15.9 and 22.0 percent, respectively [24].
Low-severity fire in early May stimulated flowering of perennial
sowthistle in a northwestern Minnesota grassland dominated by Canada
bluegrass, Kentucky bluegrass, and smooth brome (Bromus inermis). The
total number of flowering plants per unit area was greater on burned
sites than unburned controls [29].
Fire in wetlands may increase the cover of dry-adapted forbs, including
perennial sowthistle. Perennial sowthistle cover increased following
both low-severity and high-severity simulated fire in two vegetation
zones (willow savanna zone and reedgrass [Calamagrostis spp.] meadow
zone) on the Peace-Athabasca Delta, Alberta. In early July, a propane
torch was used to simulate low-severity and high-severity fires. All
aboveground biomass including litter was combusted in the low-severity
fire treatment. In order to simulate a severe fire which burns into
organic soils, 2 to 4 inches (5-10 cm) of soil was removed and the new
surface was heated with the torch for 1 minute. Perennial sowthistle
cover was measured in August, 1 year after treatments. In the willow
savanna zone, perennial sowthistle cover was 10 percent on the unburned
control and 15 percent on both burns. In the reedgrass meadow zone,
perennial sowthistle cover was 1 percent on the unburned control, 2
percent on the low-severity burn, and 4 percent on the severe burn. The
authors did not specify whether the perennial sowthistle sprouted from
undamaged rhizomes, or germinated from buried seed or recently dispersed
seed [16].
In a common reed stand in Delta Marsh, Manitoba, perennial sowthistle
seedlings established at a density of 1.4 seedlings per square foot
(15.5/sq m) 1 month after an August fire. Seedlings did not establish
after a spring fire and only a few established in the first growing
season after a fall fire. Perennial sowthistle was not present in the
prefire community; seedlings may have established from buried seed [40].
Perennial sowthistle seed germinated at a density of 43,600 seedlings
per acre (109,000/ha) in a greenhouse from soil collected from a red
pine (Pinus resinosa) stand in Minnesota which had burned 3 years
previously. Perennial sowthistle seeds were not present in the soil of
an unburned portion of the stand. The seeds were probably dispersed by
wind onto the burn from an off-site source. No perennial sowthistle
plants were present on the burn at postfire year 3 [1].
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE :
NO-ENTRY
FIRE MANAGEMENT CONSIDERATIONS :
Fire does not appear to control perennial sowthistle effectively
because fire may increase the cover and/or frequency of perennial
sowthistle [16,24,27,40] and may stimulate flowering [29].
REFERENCES
SPECIES: Sonchus arvensis | Perennial Sowthistle
REFERENCES :
1. Ahlgren, Clifford E. 1979. Emergent seedlings on soil from burned and
unburned red pine forest. Minnesota Forestry Research Notes No. 273. St.
Paul, MN: University of Minnesota, College of Forestry. 4 p. [16910]
2. Bernard, Stephen R.; Brown, Kenneth F. 1977. Distribution of mammals,
reptiles, and amphibians by BLM physiographic regions and A.W. Kuchler's
associations for the eleven western states. Tech. Note 301. Denver, CO:
U.S. Department of the Interior, Bureau of Land Management. 169 p.
[434]
3. Braidek, J. T.; Fedec, P.; Jones, D. 1984. Field survey of halophytic
plants of disturbed sites on the Canadian prairies. Canadian Journal of
Plant Science. 64: 745-751. [24018]
4. Burrill, Larry C.; Braunworth, William S., Jr.; William, Ray D.; [and
others], compilers. 1989. Pacific Northwest weed control handbook.
Corvallis, OR: Oregon State University, Extension Service, Agricultural
Communications. 276 p. [6235]
5. Clewell, Andre F. 1985. Guide to the vascular plants of the Florida
Panhandle. Tallahassee, FL: Florida State University Press. 605 p.
[13124]
6. Dittberner, Phillip L.; Olson, Michael R. 1983. The plant information
network (PIN) data base: Colorado, Montana, North Dakota, Utah, and
Wyoming. FWS/OBS-83/86. Washington, DC: U.S. Department of the Interior,
Fish and Wildlife Service. 786 p. [806]
7. Dix, R. L.; Smeins, F. E. 1967. The prairie, meadow, and marsh
vegetation of Nelson County, North Dakota. Canadian Journal of Botany.
45: 21-58. [5528]
8. Elias, Thomas S.; Dykeman, Peter A. 1982. Field guide to North American
edible wild plants. [Place of publication unknown]: Outdoor Life Books.
286 p. [21103]
9. Eyre, F. H., ed. 1980. Forest cover types of the United States and
Canada. Washington, DC: Society of American Foresters. 148 p. [905]
10. Garrison, George A.; Bjugstad, Ardell J.; Duncan, Don A.; [and others].
1977. Vegetation and environmental features of forest and range
ecosystems. Agric. Handb. 475. Washington, DC: U.S. Department of
Agriculture, Forest Service. 68 p. [998]
11. Gleason, Henry A.; Cronquist, Arthur. 1991. Manual of vascular plants of
northeastern United States and adjacent Canada. 2nd ed. New York: New
York Botanical Garden. 910 p. [20329]
12. Godfrey, Robert K.; Wooten, Jean W. 1981. Aquatic and wetland plants of
southeastern United States: Dicotyledons. Athens, GA: The University of
Georgia Press. 933 p. [16907]
13. Great Plains Flora Association. 1986. Flora of the Great Plains.
Lawrence, KS: University Press of Kansas. 1392 p. [1603]
14. Harris, Stanley W.; Marshall, William H. 1963. Ecology of water-level
manipulations on a northern marsh. Ecology. 44(2): 331-343. [17808]
15. Hickman, James C., ed. 1993. The Jepson manual: Higher plants of
California. Berkeley, CA: University of California Press. 1400 p.
[21992]
16. Hogenbirk, John C.; Wein, Ross W. 1991. Fire and drought experiments in
northern wetlands: a climate change analogue. Canadian Journal of
Botany. 69: 1991-1997. [17127]
17. Hogenbirk, John C.; Wein, Ross W. 1992. Temperature effects on seedling
emergence from boreal wetland soils: implications for climate change.
Aquatic Botany. 42(4): 361-373. [19959]
18. Kuchler, A. W. 1964. Manual to accompany the map of potential vegetation
of the conterminous United States. Special Publication No. 36. New York:
American Geographical Society. 77 p. [1384]
19. Larson, Gary E. 1993. Aquatic and wetland vascular plants of the
Northern Great Plains. Gen. Tech. Rep. RM-238. Fort Collins, CO: U.S.
Department of Agriculture, Forest Service, Rocky Mountain Forest and
Range Experiment Station. 681 p. [22534]
20. Lemna, Wanda K.; Messersmith, Calvin G. 1990. The biology of Canadian
weeds. 94. Sonchus arvensis L. Canadian Journal of Plant Science. 70:
509-532. [24019]
21. Lieffers, V. J. 1984. Emergent plant communities of oxbow lakes in
northeastern Alberta: salinity, water-level fluctuation, and succession.
Canadian Journal of Botany. 62: 310-316. [19936]
22. Marten, G. C.; Sheaffer, C. C.; Wyse, D. L. 1987. Forage nutritive value
and palatability of perennial weeds. Agronomy Journal. 79: 980-986.
[3449]
23. Merendino, M. Todd; Smith, Loren M.; Murkin, Henry R.; Pederson, Roger
L. 1990. The response of prairie wetland vegetation to seasonality of
drawdown. Wildlife Society Bulletin. 18(3): 245-251. [17645]
24. Messinger, Richard Duane. 1974. Effects of controlled burning on
waterfowl nesting habitat in northwest Iowa. Ames, IA: Iowa State
University. 49 p. Thesis. [20673]
25. Mitich, Larry W.; Kyser, Guy B. 1992. Impact of exotic weeds in the
United States. In: Lym, Rodney G., ed. Proceedings, Western Society of
Weed Science; 1992 March 10-12; Salt Lake City, UT. [Place of
publication unknown]. Western Society of Weed Science: 86-93. [20616]
26. Morin, Edith; Bouchard, Andre; Jutras, Pierre. 1989. Ecological analysis
of disturbed riverbanks in the Montreal area of Quebec. Environmental
Management. 13(2): 215-225. [13233]
27. Olson, Wendell W. 1975. Effects of controlled burning on grassland
within the Tewaukon National Wildlife Refuge. Fargo, ND: North Dakota
University of Agriculture and Applied Science. 137 p. Thesis. [15252]
28. Pederson, Roger L. 1981. Seed bank characteristics of the Delta Marsh,
Manitoba: applications for wetland management. In: Richardson, B., ed.
Midwest conference on wetland values and management: Selected
proceedings; 1981 June 17-19; St. Paul, MN. Minneapolis, MN: Freshwater
Society: 61-69. [24016]
29. Pemble, R. H.; Van Amburg, G. L.; Mattson, Lyle. 1981. Intraspecific
variation in flowering activity following a spring burn on a
northwestern Minnesota prairie. In: Stuckey, Ronald L.; Reese, Karen J.,
eds. The prairie peninsula--in the "shadow" of Transeau: Proceedings,
6th North American prairie conference; 1978 August 12-17; Columbus, OH.
Ohio Biological Survey: Biological Notes No. 15. Columbus, OH: Ohio
State University, College of Biological Sciences: 235-240. [3435]
30. Peschken, D. P. 1984. Sonchus arvensis L., perennial sow-thistle, S.
oleraceus L., annual sow-thistle & S. asper (L.) Hill, spiny annual
sow-thistle (Compositae). In: Kellcher, J. S.; Hulme, M. A., eds.
Biological control programmes against insects and weeds in Canada.
Slough, United Kingdom: Commonwealth Agriculture Bureau: 205-209.
[24021]
31. Peschken, D. P.; McClay, A. S.; Derby, J. L.; DeClerck, R. 1989.
Cystiphora sonchi (Premi) (Diptera: Cedidomyiidae), a new biological
control agent established on the weed perennial sow-thistle (Do.
Canadian Entomologist. 121: 781-791. [24020]
32. Radford, Albert E.; Ahles, Harry E.; Bell, C. Ritchie. 1968. Manual of
the vascular flora of the Carolinas. Chapel Hill, NC: The University of
North Carolina Press. 1183 p. [7606]
33. Raunkiaer, C. 1934. The life forms of plants and statistical plant
geography. Oxford: Clarendon Press. 632 p. [2843]
34. Redmann, R. E. 1972. Plant communities and soils of an eastern North
Dakota prairie. Bulletin of the Torrey Botanical Club. 99(2): 65-76.
[3639]
35. Schimming, Wanda K.; Messersmith, Calvin G. 1988. Freezing resistance of
overwintering buds of four perennial weeds. Weed Science. 36: 568-573.
[24022]
36. Sheldon, J. C.; Burrows, F. M. 1973. The dispersal effectiveness of the
achene-pappus units of selected Compositae in steady winds with
convection. New Phytologist. 72: 665-675. [24023]
37. Shorthouse, J. D. 1980. Modification of the flower heads of Sonchus
arvensis (family Compositae) by the gall former Tephritis dilacerata
(Order Diptera, f. Tephritidae). Canadian Journal of Botany. 58:
1534-1540. [24017]
38. Staniforth, Richard J.; Scott, Peter A. 1991. Dynamics of weed
populations in a northern subarctic community. Canadian Journal of
Botany. 69: 814-821. [14944]
39. Stickney, Peter F. 1989. Seral origin of species originating in northern
Rocky Mountain forests. Unpublished draft on file at: U.S. Department of
Agriculture, Forest Service, Intermountain Research Station, Fire
Sciences Laboratory, Missoula, MT; RWU 4403 files. 7 p. [20090]
40. Thompson, D. J.; Shay, Jennifer M. 1989. First-year response of a
Phragmites marsh community to seasonal burning. Canadian Journal of
Botany. 67: 1448-1455. [7312]
41. Ungar, Irwin A. 1970. Species-soil relationships on sulfate dominated
soils of South Dakota. American Midland Naturalist. 83(2): 343-357.
[11192]
42. U.S. Department of Agriculture, Soil Conservation Service. 1994. Plants
of the U.S.--alphabetical listing. Washington, DC: U.S. Department of
Agriculture, Soil Conservation Service. 954 p. [23104]
43. U.S. Department of the Interior, Bureau of Land Management, Oregon State
Office. 1985. Final Northwest Area noxious weed control program
environmental impact statement. Portland, OR. 295 p. [12796]
44. U.S. Department of the Interior, National Biological Survey. [n.d.]. NP
Flora [Data base]. Davis, CA: U.S. Department of the Interior, National
Biological Survey. [23119]
45. van der Valk, A. G. 1981. Succession in wetlands: A Gleasonian approach.
Ecology. 62(3): 688-696. [15751]
46. Ward, P. 1968. Fire in relation to waterfowl habitat of the delta
marshes. In: Proceedings, annual Tall Timbers fire ecology conference;
1968 March 14-15; Tallahassee, FL. No. 8. Tallahassee, FL: Tall Timbers
Research Station: 255-267. [18932]
47. Wein, Ross W.; Wein, Gerold; Bahret, Sieglinde; Cody, William J. 1992.
Northward invading non-native vascular plant species in and adjacent to
Wood Buffalo National Park, Canada. Canadian Field-Naturalist. 106(2):
216-224. [24014]
48. Wofford, B. Eugene. 1989. Guide to the vascular plants of the Blue
Ridge. Athens, GA: The University of Georgia Press. 384 p. [12908]
49. Zollinger, Richard K.; Kells, James J. 1991. Effect of soil pH, soil
water, light intensity, and temperature on perennial sowthistle (Sonchus
arvensis L.). Weed Science. 39: 376-384. [24015]
Index
Related categories for Species: Sonchus arvensis
| Perennial Sowthistle
|
 |
