Common Cocklebur (Xanthium strumarium ) taxon

-Cocklebur Outline
-Cocklebur Bibliography

4.11.96
Agronomy 517: Weed Biology and Ecology
Spring semester, 1996
Unit 4: Weed Species Reports
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A. Origin of name
1. Xanthium meaning yellow.
-Know in the Mediterranean region from classical
times when the fruits were used as ingredients
for hair dye thus yellow.
2. Common cocklebur (Xanthium strumarium ) is
found throughout the United States from the
south of Canada to Mexico and is a common weed
found in corn and soybean fields (44). Common
cocklebur complexes have developed in ecosystems
disturbed by man on every continent utilizing its
morpho-physiological differentiation (111).
B. Description (174).
1. Size.
a. height 20-150 cm
b. cotyledons 6.0-7.5 mm long narrow often
persist in older plants.
2. Stem.
a. erect, ridged, rough-hairy and usually
branched.
b. spotted with purple.
3. Leaves
a. simple
b. sometimes opposite at lowest node but
alternate above.
c. triangular-ovate to broadly ovate.
d. three prominent veins.
e. margins toothed or lobed.
f. surfaced rough-pubescent.
4. Petioles.
n nearly as long as blades.
5. Flowers.
a. small, green
b. unisexual staminate and pistillate heads
in separate clusters.
c. in axis of leaves at the ends of branches
and small stems
d. male- in short spike or racemes.
e. female below staminate heads on axis,
hairy with two flowers enclosed within a hard
woody bur 1-2 cm long
1. ovoid-glabose covered with spines.
2. ends with two stout incurred beaks.
3. contains two achenes which are .4-2.2
mm long..
4. Roots.
a. lateral 2.1 m.
b. vertical- down to 1.3 m.
c. under anaerobic conditions may develop
large air spaces.

TAXONOMIC STATUS.

A. Relatives of Xanthium
1. Tribe- Ambrosieae.
2. Family- compositae.
3. Species- spinosum in meadows worldwide.
4. X. strumarium common along shores and
cultivated fields.
5. Datura stramonium L.
a. seedlings have similar long narrow
cotyledons and broad oval leaves.
b. differ with a sour odor and smooth
hairless stem and leaves.
c. X. strumarium has bur clinging to the
seedling root.
B. "As a matter of fact Xanthium taxa are very confused
at the present time." (L–ve and Dansereau, 1958) (98).
C. Many of the so called species described as European
actually have their origin in America.
D. Central and or /South American origin which spread
over the continents north and southward?
E. Two distinct species(98).
1. X. spinosum L. - relatively stable species.
2. X. strumarium L.- enormously variable species.
a. intense inbreding with occasional
outbreeding is responsible for enormous
variation.
b. results in small local but unstable taxa.
F. Eastern North American Xanthiu(98).
1. Primarily a beach plant.
2. Prefers open habitat.
3. Enters into ruderal habitats only as long as
they are open and unshaded.
G. Taxonomist argue do we have more than one
species(98).
H. Linnaeus split Xanthium.
1. X. strumarium (Europa).
2. X. oriental
a. China.
b. Zeylona.
c. Joponica .
d. plus the larger more robust American and
Canadian plants.
I. Miller 1770's
1. X. strumarium native to Europe.
2. X. canadensea native to North America.
3. X. chinese in which Miller believed came from
China.
J. Moretti 1820's X. italican thought from Italy.
1. From the river Po.
2. Beach habitats.
3. now common over southern Europe.
4. Also wide spread in North American.
5. Found in Hawaii.
6. True homeland in American.
K. Danish botanist Schouw 1840's X. cavanillesii from
Buenos Aires.
1. Xanthium of Brazil of the same type.
2. Only indigenous type of South America.
a. along rivers and streams
b. on cultivated subtropical, and warm-
temperate areas.
c. reaching up into Mexico.

3. Old World cavanillesii.
a. Spain.
b. North Africa.
c. South African Sheep grazing problem.
L. Widder theory 1920's. X. cavanillesii type from
which certain North American Xanthium derived.
1. Californicum west.
2. Saccharatum east.
3. Cavanillesii Type also pensylvanium type- -
some dissent drastically.
M. Wallroth's pugens 1840's.
1. Seed on raccoon tail.
2. Raccoon did not occur in Europe.
3. X. pensylvanicum.
4. X. saccharatum.
5. very hairy glandular fruit.
6. cavanillesii type.
N. L–ve 1950's pensylvanicum.
1. Ranges practically all over North America.
2. Affinities to.
a. italicum.
b. echinatum.
c. cavanillesii.
d. chenense.
O. L–ve 1950's X. oviforme (Washington &;Oregon State).
1. Immense burs.
2. Long hooked beaks.
3. Western type but has I.D. in central Illinois.
4. Widder thought oviforme a mutant type.
P. Hybridus(98).
1. Swarm of types from pensylvanicum to italicum.
2. Covers the entire U.S..
3. In Europe italicum is from this complex.
4. Appeared in Italy around 1800 at the time of
early Italian migration.
Q. Old World(98).
1. Strumarium only true native of Old World.
2. Italicum and oriental introduced from America.
R. Center of origin of genera related to Xanthium.
1. Iva, Ambrosia, Franseria.
2. Have their centers of origin in the dry areas
of Central America, Mexico.
GEOGRAPHY AND DISTRUBUTION(98).

A. General geography.
1. Lat. 45o S. And 50o N. in the western
hemisphere.
2. Lat. 30o S. and 60o N. in the eastern
hemisphere.
3. Scandinavia reaches 60o N Lat..
4. Southeast Asia between. 10o S and 40o N Lat..
B. Vermont.
1 Highest number of Xanthium complexes.
2. Crossroads between St. Lawrence and Hudson
rivers.
3. Open to the west via the gap in the eastern
mountains.
4. human activity- long time.
C. Natural Xanthium limitations.
1. Preference to compact sandy soils slightly
moist.
2. Can compete with delicate small annuals but not
with sod.
3. Does not venture under shade.
4. Fruit dispersal mostly by water.
5. Favorable Xanthium conditions cannot be found
over a large area.
6. Perennial grasses will crowd it out ex: Agropyron
repens.

HABITAT(174).
A. Not common in the mountains.
B. Heat- high temperatures above 35o C particularly during
the dark period will inhibit floral induction.
C. Soil pH will tolerate from 5.2 to 8.0 and will tolerate
frequent flooding and saline conditions.

POPULATION DYNAMICS TWO TYPES OF POPULATIONS(174).

A. Population along shores or watercourses which is a
small ephemeral and homogeneous.
B. Population in rudural habitat.
1. Large, dense and heterogeneous.
2. Tall seeds and abundant seed.
A. Both types of populations are continually shifting to
newly disturbed areas.
B. Under favorable conditions X. strumarium can quickly
colonize a habitat.

REPRODUCTION.

A. Flowing anthesis ripening.
1. Late summer flowering (August - September) irrespective
of the size reached by the plant, whether it has two leaves
or hundreds(174).
2. Flowering is determinate(174).
3. Sex ratio(163).
a. most species become more female as plant size
increases.
b. cocklebur behave opposite- the mass of male flowermass
of the female flower increase with plant size and resource
status.
4. Vegetative parts strictly annual.
5. Pollen.
a. grain 22-38m in diameter.
b. non-adhesive.
c. weakly spined.
d. no known insect pollinators.

6. Inbreeding(98).
a. arrangement of flowers favors inbreeding.
b. males flowers are at top of the stalk
above the female flowers.
c. stamens shed pollen a day or two before
stigmata are receptive.
d. inbred is the rule outbreeding an
occasional occurrence.
e. chromosome number 2n=36.
f. formation of sterility barriers is very
slow.
g. after hybridization new gene combinations
soon become stable due to the high degree of
inbreeding.
h. no known apomixs in Xanthium.
i. 88% self pollinated(174).
7. Maybe partial genetic incompatibility between
Eurasian and American plants.
B. Seed production.
2. 500 burs/plant Illinois(174).
3. 2300 burs/plant India(83).
4. Lechowicz upubl. Reported 5400 burs/plant in Quebec.
5. Nadeau (1961) reported 24 fruits a branch and 18
branches per plant.
6. Weaver upubl. Reported 400 bur/plant early planting and
80 bur/plant late planting.
7. Average thought to be 70-600 bur/plant(174).

SEED GERM &;FORM(174).

A. Certain amount of heat is necessary for germination.
B. Late germ end of June, early July.
C. Seed germ, two seed/bur.
1. Two seeds one is pushed out of hollow.
2. Lower seeds germinates next season or a latter
season.
3. Can get simultaneous germination of the two
seeds.
4. More than likely different types of Xanthium differ
with respect to seed germination.
D. Seed viability.
4. Is usually at least 80% at time of production.
5. May have more than 2 seeds per bur.
6. After 12-16 weeks of dry storage only lower seed will
germinate at 21o C at 30o C both will germinate.
7. Germination max. is at temperatures of 30/20o or 33/25o
.
8. Soil depth of max. germ is 1.8 cm.
9. Light is not required for germination.
10. Seldom germinate on the soil surface or if buried over
15 cm below the soil surface.
11. Have a high moisture requirement
12. Needs at least 75% field H2O Capacity.
A. Seed life(39).
5. Will decrease markedly after 18 months.
6. 6 mo of burial germ went from 99% to 66% and down to
18% after 30 mo regardless of depth.
7. Xanthium overwinter at 2.5 to 15.2 cm germ from 50% to
90%
.
PERENATION - overwinter as a seed on or below the surface of
the soil.

PHYSIOLOGICAL DATA.
A. Short day plant(109).
1. Northwest origin need only 7-7.5 hr critical dark
period to initiate flowering.
2. Texas and Mexico plants need 10.75 hr of critical dark.
3. Iowa 9 hr of critical dark.
4. Uruguay &;Brazil 10-10.25 hr critical dark.
A. The ease of producing new photoperiodic response
through hybridization indicates that X.
strumarium has an enormous potential for adaptation.
C. Quantitative rather than qualitative short day
response.
D. Leaves most responsive to photoperiod at the stage of
rapid elongation and cellular differentiation of the lamina.
E. Light flashes longer than 1 min. during the dark
period may inhibit floral induction.
F. Photosynthesis(174).
1. Stomate respond to light rather than intercellular CO2.
2. Chloroplast in every cell type.
3. conductance of X. strumarium greater than soybean
(Glycine max. L.) also a C3 plant.
4. N.
a. can assimilate N as either nitrate or ammonia
b. seeds are 6.6% N and account for 95% N reallocated in
plant.

PARASITES OF XANTHIUM.

A. Insects that attack Xanthium(174).
1. A moth Phaneta imbridana.
a. oviposits on the bur
b. attacks the bur.
2. Trypetid fly Euarest aequalis(110).
3. Smaller burred populations have higher attack
rates.
4. Stem boring beetle Coleopterai cerambycidae.
a. imported to Australia for biocontrol.
b. oviposit on top of stem.
c. larvae overwinter in the root.
d. multiple attack result in larvae
mortality.
B. Fungus of Xanthium(174).
1. Rust Puccinia xanthii.
a. attacks both Xanthium and Ambrosia.
b. infected plants mature more fast.
c. infected plants have underweight seeds.
2. Septoria xanthaii
3. Albugo tragopoganis.
4. Bertrysis cinorea.
5. Cercospera xanthicola.
6. Colletotrichum xanthii.
7. Mycophaerella xanthicola.
8. Phymatotrichum omnivorum.
10. Plasmapara halstedii.
11. Puccinia canalicalata.
12. Rhabdospora xanthaii.
13. Erysiphe a powder mildew is frequent on plants
of chinese complex in southern U.S.(110).

PHYTOCHEMISTRY(113).

A. Fruits once a source of medical drugs.
B. Fruits boiled in water still drank as a tea in some
parts of Asia.
C. Swine poisoning (Carboxyatractyloside) from sprouts of
cocklebur(165).
3. Lesions.
4. Hypoglycemia.
5. Death among swine probably more numerous than is
generally recognized.
6. Low palatability has assured survival under intense
utilization of domesticated animals.
C. Sesquiterpene lactones(113).
4. Xanthinin.
5. Xanthumin.
6. Xanthanol 2A.
7. Xanthumanol 2B.
8. Xanthatin.
9. Xeacetosyl xanthumin.
10. Xanthinosin.
11. Tamentosin.
12. Insecticidal inhibit insect feeding.
13. Herbicidal inhibit seed germination.
14. Treatment of.
a. scrofula.
b. fever.
c. herpes.
d. cancer- anti-tumor toxicity.

ECONOMICS.

A. Burs will devalue the wool of sheep.
B. Young seedlings will poison swine.
C. A 60% yield reduction with 8 common cocklebur/7.3m of
row and a 10% yield loss with 6 common cocklebur/17m and
50% yield loss for 45 cocklebur/17m row over a 2-yr average
in soybeans has been reported (8).
D. Common cocklebur is considered the most competitive
annual weed in North American soybean production (8).
E. 90% yield loss in cotton with 48 common cocklebur/7.3m
of row. Was shown by Barrentine(19).

HERBICIDES FOR XANTHIUM CONTROL.

A. Metribuzin- preplant.
B. Bentazon- post.
C. Acifluorfen- post.
D. Dicamba- post.
E. Chlorimuron
F. Imazethapyr post.
G. Imazaquin post
H. Bromoxynil post
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