Foxtail (Setaria spp.) taxa
Foxtail (Setaria spp.) taxa
-Foxtail spp. Outline
-Foxtail spp. Bibliography (1996a)
-Foxtail spp. Bibliography (1996b)
a. giant foxtail (S. faberii)
b. green foxtail (S. viridis)
c. knotroot foxtail (S. geniculata)
d. yellow foxtail (S. glauca)
e. bristly foxtail (S. verticillata)
Take a special tour of the "FOXTAIL BIOLOGY PROGRAM" WWWeb site
4.22.96
Agronomy 517 Weed Biology Ecology
Spring Semester1996
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Species Written Report: Foxtails Setaria spp.
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Submitted By Randy Thornhill
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Introduction
Origin- Progenitor of the Setaria genus most likely originated in Africa which contains 74 of its125 known species (Rominger 62).
43 species from 3 subgenera Ptychophyllum (6spp.), Paurochaetium (10 spp.), Setaria (27spp.) are found in North America (Rominger 62)
This report contains specific information on 5 Setaria spp. ;
S. viridis, S. faberii, S. geniculata, S.
glauca, and S. verticillata.
Generalized description of the morphology of this genus.
A. Growth habit (Gould 68)
1. Tufts or clumps (cespitose)
2. Erect or geniculate culms
3. Often branching at the base
B. Reproduction
1. Very low rate of outcrossing(2% to 7% )(Li et al 35)
2. Moderate incidence of Cleistogamy (Watson and Dallwitz 92)
3. Highly apomictic (Watson and Dallwitz 92) &;(Rao 85)
B. Leaf (Gould 68)
1. Leaves generally flat and thin
2. Usually glabrous (except some faberii)
3. Petiole-like constriction between blade and sheath
4. Ligule present
C. Inflorescence (Gould 68) ( Manual of Grasses)
1. Usually contracted dense
2. Spikelets subsessile on main axis
3. Spikelets subtended by 1 to several bristles
4. Spikelets disarticulate above the bristles(retorse in verticillata)
D. Flowers (Watson and Dallwitz 92)
1. Proximal incomplete florets
2. Stamens(3); free, fleshy, glabrous
3. Anthers; not penicillate
4. Ovary; glabrous
5. Styles free at their bases
6. Stigmas(2); white or red pigmented
E. Seeds (Watson and Dallwitz 92)
1. Glumes and lemma glabrous
2. Prominently nerved(veins)
3. First glume short
4. Second glume and lemma of sterile floret equal length
5. More frequently second glume 1/2 to 2/3 as long (Pohl 78)
6. Endosperm, without lipid, only simple starch grains
F. Basic Chromosome number; Base number x=9 or x=10 (Watson 92)
1. Ploidy levels 2, 4, 6 and 8
2. x=9 (viridis)
3. x=18 (faberii)
4. x=9 or18 (verticillata)
5. x=18 (glauca)
6. x=18 or 36 (geniculata)
G. Habitat ( Bubar and Morrison 84)&(Lee;et al 81)
1. Frequently disturbed sites, waste areas, roadsides
2. Open areas with full sunlight
3. Rural and Urban locations
4. Soil type not limiting
5. Adequate moisture is necessary
H. Economic Importance: Significant weed species (Watson and Dallwitz 92)
1. S. adhaerens
2. S. barbata
3. S. faberi
4. S. glauca
5. S. gracilis
6. S. verticillata
7. S. viridis
Individual Species Characteristics
I. Setaria viridis (L.) Beauv.
Found throughout North America primarily in temperate regions infrequent in southern
states and mountains, introduced from Europe(Pohl 78)
A. Plant Morphology
1. Growth Habit
a. annual, branching at base(tillers)
b. sometimes geniculate-spreading
c. 20-100 cm. tall (Pohl 78), some 1.8-2.5 meters tall( Schreiber 71)&;(Rao et al 85)
d. shallow roots (Pohl 78)
2. Leaves
a. leaf blades flat, glabrous
b. 1 cm. wide
c. 15 cm or less in length
3. Inflorescence (Pohl 78)
a. green or purple
b. cylindric but tapering
c. usually less than 10 cm long
d. 1 to 3 bristles below each spikelet
e. 3 or more pannicle types
4. Seeds
a. lemma, finely transversely wrinkled
b. Swollen palea, not highly convex
c. 1.8-2.5 mm long
d. 1-1.3 mm wide
e. glume and sterile lemma nearly covering fertile floret
f. mass in g/1000 seeds 0.82 (Schreiber 71) , 0.95 mg (Haar and Dekker 95)
g. number/panicle 370 (Schreiber 71)
451 (Haar and Dekker 95)
h. typically completely dormant at maturity
5. Genetic Structure (Wang et al 95)
a. diploid 2n=18
b. little genetic polymorphism
c. high population genetic differentiation
B. Common names
1. Green foxtail
2. Pigeon grass
3. Green bristlegrass
C. Varieties of Green Foxtail
1. Setaria viridis var. viridis (Linneaus)
2. Setaria viridis var. weinmanni (R. &;S.) Brand
3. Setaria viridis var. major (Gaud.) Posp.
4. Setaria viridis var. robusta-alba Schreiber
5. Setaria viridis var. robusta-purpurea Schreiber
6. Setaria viridis var. pyncoma (Steud.) Henrard et Nakai
7. Setaria viridis var. pachystachys (Franch et Savat.) Makino et Nemoto
D. Economic Importance
1. # 1 food for wildlife (Martin 61)
2. Imported to North America via farming practices (Pohl 50)
3. Studies of the direct effects of S. viridis var major on soybean
production found that production was reduced 21 to 41% when no control methods were
employed. (Harris and Ritter 1987)
4. Second most important weed group in the U.S.
(Holm et al 77)
5. Increased cost of cleaning crops.
E. Characteristics that make S. viridis a successful weedy plant
1. Competitiveness in disturbed habitats (Wang et al 95)
a. early germination
b. fast early growth
c. C4 photosynthesis: adapted to a wider range of temperatures than C3 plants and weeds.
2. Dormancy
a. complete dormancy and no dormancy
(Vanden Born 71)
b. longevity of seed in the seed Bank
(Schreiber 77)
3. Genotypic Plasticity (Li et al 45)
a. crosses between S. viridis and S. italica
b. cross pollenation possible but not required
c. polyploidism- able to carry less effective but useful traits without loss of
"fitness"
d. S. viridis varieties (see above)
4. Phenotypic Plasticity
a. light and temperature response (Schreiber 71) &;(Bubar and Morrison 84)
b. tillering (75 or more)(Santelman et al 62) (Vanden Born 71)
c. emergence from soil depth of 12 cm
(Vanden Born 71)
5. Seed number
a. many seeds produced (Haar and Dekker 95) &; (Schreiber 71)
b. variety of dormancy states posssible
(Dekker et al 96)
6. Seed Dispersal
a. wind
b. water
c. wildlife
d. agricultural practices
7. Apomictic Reproduction
a. one plant sufficient for propagation in new area
8. Response to herbicide
a. resistance to some herbicides (atrazine, trifluralin) (Morrison et al 89)
b. herbicides recommended for control
1. pre-emergence
a. Metolachlor
b. Metolachlor + Atrazine
c. Butylate
d. Metolachlor + Paraquat
2. post-emergence
a. Metolachlor + Paraquat
b. Acifluorfen
II. Setaria faberii Herrmann
Found throughout North America especially in temperate agricultural areas (row crop
farming systems). First reported in 1931 (Pohl 50). Probably arrived in a shipment of
Chinese millet (Hitchcock 71)
A. Plant Morphology
1. Growth Habit
a. annual, branching at base(tillers)
b. sometimes geniculate-spreading
c. some 0.1-3 meters tall( King 52)&;
(Rao et al 85)
d. shallow roots (Pohl 78)
2. Leaves
a. leaf blades flat, usually pubescent
b. 1.5 cm. wide
c. 15 to 30 cm. in length
3. Inflorescence (Schreiber and Oliver 71)
a. green or purple
b. cylindrical and drooping from base
c. usually more than 6-20 cm long(Rominger 62)
d. 1 to 6 bristles below each spikelet
4. Seeds
a. lemma, strongly transversely wrinkled
b. swollen palea, highly convex
c. 2.2-2.9 mm long
d. 1.1-1.5 mm wide
e. glume and sterile lemma covering 2/3 fertile floret
f. mass in g/1000 seeds1.5-2.2
(Kawano &;Miyake 83)
g. number/plant 61-5,851 (Kawano &;Miyake 83)
h. typically completely dormant at maturity
5. Genetic Structure (Wang et al 95)
a. tetraploid 2n=36 (allotetraploid)
(Till-Bouttraud et al 92)
b. no allozyme variation, nearly invariant
c. theoretically at the minima for diversity
B. Common names
1. Giant foxtail
2. Nodding foxtail
3. Giant bristlegrass
4. Chinese foxtail
C. Varieties of Giant Foxtail
1. Setaria faberii (Herrm) [syn. S macrocarpa Lucznic]
2. Setaria faberii var. triazine resistant
D. Economic Importance
1. # 1 food for wildlife (Martin 61)
2. Imported to North America via Chinese millet
3. Studies of the direct effects of S. faberii on soybean 27% and corn 14%
production found that production was reduced (Knake and Slife 65)
(Knake 87)
4. Second most important weed group in the U.S.
(Holm et al 77)
5. Increases cost of cleaning crops.
E. Characteristics that make S. faberii a successful weedy plant
1. Competitiveness in disturbed habitats (Wang et al 95)
a. early germination
b. fast early growth
c. C4 photosynthesis: adapted to a wider range of temperatures than C3 plants and weeds.
2. Dormancy
a. complete dormancy and no dormancy
(Vanden Born 71)
b. longevity of seed in the seed Bank(13 yrs)
(Schreiber 77)
3. Genotypic Plasticity
a. crosses between S. faberii andS. viridis (Willweber-Kishimoto 62)
b. cross pollenation possible but not required
c. polyploidism- able to carry less effective but useful traits without loss of
"fitness"
d. not competitive with established vegetation (Rominger 62)
4. Phenotypic Plasticity
a. light and temperature response (Schreiber 64) b. tillering (Santelmann et al 62)
c. emergence from soil depth of 10 cm
(Buhler and Mester 91)
5. Seed number
a. many seeds produced 831/panicle
(Haar and Dekker 95)
775/panicle (Schreiber and Oliver 71)
b. variety of dormancy states posssible
(Dekker et al 96)
6. Seed Dispersal (Rominger 62)
a. wind
b. water
c. wildlife
d. farm machinery
7. Apomictic Reproduction
a. one plant sufficient for propagation in new area
b. viable for long time in soil seed bank
8. Response to herbicide
a. resistance to some herbicides (atrazine, trifluralin) (Colby et al 89)
b. herbicides recommended for control
1. pre-emergence
a. Metolachlor
b. Metolachlor + Atrazine
c. Butylate
d. Metolachlor + Paraquat
2. post-emergence
a. Metolachlor + Paraquat
b. Acifluorfen
III. Setaria glauca (L.) Beauv. Previously
S. lutescens (Weigel) F. T. Hubbard
Found throughout North America primarily in temperate regions in southern states and
high altitude in Jamaica, introduced from Asia (Wang et al 95)
A. Plant Morphology
1. Growth Habit
a. annual, branching at base (tillers)
b. erect to prostrate
c. mostly 50-100 cm. tall (Pohl 78)
2. Leaves (Hitchcock 71)
a. leaf blades twisted in loose spiral
b. 1 cm. wide
c. 25 cm or less in length
d. long hairs at base of leaves
3. Inflorescence (Pohl 78)
a. yellow, few purple bristle tips
b. cylindric spikelike
c. usually 5 to 10 cm long and 1cm diameter
d. 5 to 20 bristles below each spikelet
4. Seeds
a. lemma, very strongly rugose
b. palea, concave
c. 2.5-3 (or 3-3.5)mm long
d. 1.8-2.1(or 2-2.2) mm wide
e. sterile lemma covering 1/2 fertile floret
f. mass in g/1000 seeds 3.87 (Haar 95)
g. number/panicle 115 (Haar 95)
h. typically completely dormant at maturity
5. Genetic Structure (Wang et al 95)
a. euploid series 2n=18, 36, 44, and 72
b. aneuploid 2n=36 and 72
c. strong population genetic differentiation
B. Common names (Rominger 62)
1. Yellow foxtail
2. Yellow bristle grass
3. Pigeon grass
C. Varieties of Yellow Foxtail
1. Setaria glauca (L.) Beauv.
D. Economic Importance ?
1. # 1 food for wildlife (Martin 61)
2. spread by agronomic practices
(Bubar and Morrison 84)
3. competitive in new stands of alfalfa(Schoner et al 77)
4. damage to livestock by bristles (Schoner et al 77)
5. crop losses of 16% for wheat,15% for soybeans and 11% for oats (Santelmann et al 62)
E. Characteristics that make S. glauca a successful weedy plant
1. Competitiveness in disturbed habitats
(Santelmann et al 62)
a. protracted period of germination
b. fast growth after establishment (20-70 days)
c. C4 photosynthesis: adapted to a wider range of temperatures than C3 plants and weeds.
2. Dormancy
a. highly dormant (Kollman 73)
b. slightly dormant (Norris and Schoner80)
c. viability lost rapidly(within 5 years)
(Willweber-Kishimoto 62)
1. first year germinability 80%
2. second year 10-20%
3. slowed loss in subsequent years to 0%
d. seed hardness (Stoller and Wax 74)
3. Genotypic Plasticity
a. cross pollenation possible but not required
b. polyploidism- able to carry less effective but useful traits without loss of
"fitness"
c. high relative seed mass ( 5x )
( Kawano &;Miyake 83)
4. Phenotypic Plasticity
a. light and temperature response
(Bubar and Morrison 84)
b. tillering (up to 55) (Santelman et al 62) c. many biotypes (Schoner et al 78)
c. emergence from soil depth of 12 cm
5. Seed number
a. many seeds produced (5,486) (Manthey 84)
b. seeds produced quickly in response to mowing (Schoner et al 78)
c. production delayed by agronomic practice
6. Seed Dispersal
a. wind
b. water
c. wildlife
d. agricultural practices
7. Apomictic Reproduction
a. one plant sufficient for propagation in new area
8. Response to herbicide
a. trifluralin reduced seed reserves (Manthey 84)
b. herbicides Recommended for control
1. pre-emergence
a. Atrazine
b. Butylate
2. post-emergence
a. Paraquat
b. Acifluorfen
IV. Setaria geniculata (Lamarck) Beauv.
Native to the Americas, coastal CA to MA and Argentina and Chile through central America
Found in North America primarily in Atlantic and Gulf Coastal Plains, but extends up the
Mississippi to Illinois and southeastern Iowa. Occurs sparingly in the southwest. (Pohl
50)
A. Plant Morphology
1. Growth Habit
a. perennial, produces rhizomes
branching at base(tillers)(Hitchcock 71)
b. erect or geniculate
c. tufted or solitary
c. 30-120 cm. tall (Rominger 62)
d. most widely distributed foxtail in the Americas
(Rominger 62)
2. Leaves (Rominger 62)
a. leaf blades flat, scabrous on upper surface
b. glabrous lower surface
c. .2-.8 cm. wide
d. 25 cm or less in length
e. sometimes bearing long hairs near stem
3. Inflorescence (Hitchcock 71)
a. yellow or purple
b. cylindrical
c. 3-8 cm long (Rominger 62)
d. antrorsely barbed bristles 2-12 mm
(Rominger 62)
e. 4 to12 bristles below each spikelet(Rominger 62)
4. Seeds
a. lemma, finely transversely wrinkled
b. convex palea
c. elliptical 2-2.8 mm long
d. 1.5 mm wide
e. glume and sterile lemma covering 1/3 to 1/2 of the fertile floret
h. typically completely dormant at maturity
5. Genetic Structure
a. diploid 2n=36,72 (Rominger 62) &(Brown;48)
b. genetic polymorphisms (Wang et al 95)
c. high population genetic differentiation
(Wang et al 95)
B. Common names
1. Knotroot foxtail
2. Yellow bristlegrass
3. Yellow foxtail
C. Varieties of Knotroot Foxtail
1. Setaria geniculata (Lamarck) Beauv.
D. Economic Importance
1. # 1 food for wildlife (Martin 61)
2. Not studied (possibly the same as S. glauca)
E. Characteristics that make S. geniculata a successful weedy plant
1. Competitiveness in disturbed habitats
a. grows in salt marshes along coast
b. pastures and open areas
c. C4 photosynthesis: adapted to a wider range of temperatures than C3 plants and weeds.
d. reproduces by seed and rhizomes
2. Dormancy
a. assumed similar to other foxtails (unknown)
3. Genotypic Plasticity (Li et al 45)
a. polyploidism- able to carry less effective but useful traits without loss of
"fitness"
4. Phenotypic Plasticity
a. exteme variability in morphology
(Rominger 62)
b. tillering
c. easily mistaken for S. glauca (Pohl 50)
5. Seed number
a. no information found
6. Seed Dispersal
a. wind
b. water
c. wildlife
7. Apomictic Reproduction
a. one plant sufficient for propagation in new area
8. Response to herbicide
a. not studied
V. Setaria verticillata (L.) Beauv.
Found throughout North America primarily in temperate regions, absent from southern U.S.,
as well as Central or South America Introduced from Europe(Rominger 62)
A. Plant Morphology
1. Growth Habit
a. annual, branching at base(tillers)
b. geniculate (Rominger 62)
c. 30-100 cm. tall (Rominger 62)
2. Leaves
a. leaf blades flat, glabrous, acuminate, scabrous
(Rominger 62)
b. 1-1.5 cm. wide
c. 10-25 cm or less in length
d. occasional scattered hairs on upper surface
3. Inflorescence (Rominger 62)
a. yellowish-green or purple
b. cylindric but tapering
c. 5- 15 cm long
d. 1 bristle (retorsely barbed) below each spikelet
4. Seeds
a. lemma, finely transversely wrinkled
b. Swollen palea, not highly convex
c. 2-2.2 mm long
d. 1 mm wide
e. first glume 1/3 of spikelet
f. second glume nearly covering spikelet
g. seeds rounded at tip
h. typically completely dormant at maturity
5. Genetic Structure
a. diploid 2n=18, 36 (Darlington and Wylie 55) or 2n=54 (Bala &;Sachdeva 90)
b. genetic polymorphisms not studied
c. population genetic differentiation not studied
B. Common names
1. Bristly foxtail
2. Bristlegrass
C. Varieties of Bristly Foxtail
1. Setaria verticillata var. ambigua (Guss.) Parl
D. Economic Importance
1. Very successful in the vineyards of California (Rominger 62)
2. Imported into North America (Rominger 62)
3. Found in gardens and greenhouses
(Lee and Cavers 81)
4. Inflorescence used to protect grain from rats
(Kegode 91)
5. Wild reservoir for Cereal Chlorotic Mottle Virus (CMV) a disease causing virus of Oats,
Durum Wheat and Barley in Northern Africa and Australia ( Lockhart 86)
6. Common in maize, wheat, potatoes,sugarcane, coffee, tea and pyrethrum in Kenya ( Baker
and Terry 91)
E. Characteristics that make S. verticillata a successful weedy plant
1. Competitiveness in disturbed habitats
a. early germination
b. maintained rapid relative growth rate (Ernst and Tolsma 92)
c. C4 photosynthesis: adapted to a wider range of temperatures than C3 plants and weeds.
2. Dormancy
a. not studied
b. longevity of seed in the seed Bank not studied 3. Genotypic Plasticity ()
a. crosses between S. italica and S. verticillata 0.5% (Till-Bottraud 92)
b. cross pollenation possible but not required
c. polyploidism- able to carry less effective but useful traits without loss of
"fitness"
d. S. verticillata (2) varieties
e. greater densities than other grasses
(Baker and Terry 91)
4. Phenotypic Plasticity
a. less tolerant of shade than either S. viridis or
S. glauca (Lee and Cavers 81)
b. fewer tillers produced (Lee and Cavers 81)
5. Seed number not reported
6. Seed Dispersal
a. wind,
b. water
c. wildlife this is especially useful for this species due to the barbs, which become
entangled in fur and hair
7. Apomictic Reproduction
a. one plant sufficient for propagation in new area
8. Response to herbicide
a. pendimethalin tank mix with atrazine
(Baker and Terry 91)