Cambodian Weeds

8/14/2019 Cambodian Weeds

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r o b e r t m a r t i n & p o

W e e d s o f

U p l a n d c r o p si n c a m b o d i a

A weed identification guide for farmers and extension workers

in the upland cropping systems of Cambodia. Sponsored

by the Australian Centre for International Agricultural

Research, the NSW Department of Primary Industries,

and the Cambodian Agricultural Research and

Development Institute.


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Tit: Wds of Upand Crops in Cambodia

Authors: Robrt Martin and Po ChanthyPubishd by NSW Dpartmnt of Primary Industris

Stat of Nw South Was [2007]

Copyright of this pubication, and a th information it contains

jointy vsts in th Cambodian Agricutura Rsarch & Dvopmnt

Institut and th Stat of Nw South Was (NSW Dpartmnt of

Primary Industris). Ths partis grant prmission for th gnra

us of any or a of this information providd du acknowdgmnt isgivn to its sourc.

First pubishd Sptmbr 2007

ISBN 978 0 7347 1862 4

DISClAIMeR

Th information containd in this pubication is basd on knowdgand undrstanding at th tim of writing ([Sptmbr 2007]).

Howvr, bcaus of advancs in knowdg, usrs ar rmindd of

th nd to nsur that information upon which thy ry is up to

dat and to chck currncy of th information with th appropriat

officr of NSW Dpartmnt of Primary Industris or th usrs

indpndnt advisr.

job #8023


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r o b e r t m a r t i n & p o

W e e d s o f

U p l a n d c r o p si n c a m b o d i a

A weed identification guide for farmers and extensio

in the upland cropping systems of Cambodia. Spons

the Australian Centre for International Agricultural Rthe NSW Department of Primary Industries, and the

Agricultural Research and Development Institute.


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WEEDS OF UPLAND CROPS IN CAMBODIA

f

Aeschynome ne americana 39

Alysicarpus monilifer 40

Cassia occidentalis 41

Cassia tora 42

Centrosema pubescens 43

Clitoria ternatea 44

Crotalaria striata 45

Mimosa invisa 46

Mimosa pigra 47

Mimosa pudica 48

Macroptilium atropurpureus 49

l

Hyptis suaviolens 50

mv

Abelmoschus moschatus 51

Abutilon indicum 52

Pentapetes phoenicea 53

Sida acuta 54

Sida rhombifolia 55

Urena lobata 56

ng

Boerhavia diffusa 57

pPassiflora foetida 58

p

Brachiaria mutica 59

Brachiaria reptans 60

Cynodon dactylon 61

Dactyloctenium aegyptium 62

Digitaria adscendens 63

Echinochloa colona 64

Eleusine indica 65

Imperata cylindrica 66

Sorghum halepense 67

pu

Portulaca oleracea 68

ruBorreria alata 69

Hedyotis diffusa 70

Richardia brasiliensis 71

s

Cardiospermum halicacabum 72

s

Physalis angulata 73

t

Corchorus olitorius 74

V

Stachytarpheta indica

V

Cayratia trifolia 76

G 77

r 81


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a cuk

Urena lobata 56

ag bk

Cardiospermum halicababum 72

a Ku

Achryanthes aspera 8

a

Clitoria ternatea 44

bk p

Phyllanthus niruri 38

cu t

Cyanotis axillaris 25

cgkg sv

Crotalaria striata 45

cug bgkg

Alternanthera sessilis 9

cug Kg p

Trianthema portulacastrum 7

dg Ku

Cassia tora 42

du c e

Spilanthes paniculata 17

du s o

Alysicarpus monilifer 40

K cu

Portulaca oleracea 68

K c

Hedyotis diffusa 70

Ku yu

Centrosema pubescens 43

Kg b s

Sida acuta 54

Kg b s n

Sida rhombifolia 54

Kg K

Ageratum conzoides 14

K ag

Cardiospermum halicacabum 72

K bk

Ruellia tuberosa 6

K

Pentapetes phoenicia 53

Kv cuk

Cyperus rotundus 31

K cuv p

Corchorus olitorius 74

lg Kvg

Jatropha curcas 36

lg Kvg K

Jatropha gossypiifolia 37

m p

Borreria alata 69

mu puk p

Abelmoschus moschatus 51

mk cg

Eclipta alba 16

m

Cleom

m

Cleom

m

Cleom

m

Hyptis

pg p

Physa

p

Ipomo

p

c o n t e n t s b y K h m e r n a m e


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p K d

Mimosa invisa 46

p K yk

Mimosa pigra 47

p b

Amaranthus spinosus 10

p dug

Amaranthus viridus 11

p t

Boerhavia diffusa 57

pk c

Acalypha indica 32

p d

Heliotropium indicum 21

s cu

Ipomoea triloba 29

sk Ku

Cassia occidentalis 41

sv m p

Passiflora foetida 58

suv Kg

Imperata cylindrica 66

s p

Celosia argentea 12

s t

Commelina benghalensis 26

suk b

Trichosanthes cucumerina 30

s bg

Brachiaria mutica 59

s bk K

Echinochloa colona 64

s c c

Cynodon dactylon 61

s cug K

Dactyloctenium aegyptium 62

s K

Brachiaria reptans 60

s K s-

Stachytarphe ta indica 75

s sg

Eleusine indica 65

s sk m

Digitaria adscendens 63

su ru

Vernonia cinerea 20

s a

Aeschynomon e americana 39

s Kk

Syndrella nodiflora 18

t K

Abutilon indicum 52

tg

Sorghum halepense 67

tu K

Chromolaena odorata 15

tuk d

Cham

tuk d

Eupho

V Ku

Macro

V m

Ipomo

V t

Cayrat

V t

Centel


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Weeds can be a problem in the production of upland crops

because they reduce yield by competing for resources

essential for growth, such as water, nutrients and light.Weeds can also make it difficult to harvest the crop, and

seeds of some species can contaminate the grain and reduce

its quality and price.

traditional practices

Weeds have been a problem since the beginning of

agriculture, and until the advent of herbicides during the

1940s, the traditional practices have been hand-weeding,

cultivation and toleration (Holm et al. 1977). In Cambodia,

weeds are still largely managed by traditional practices

(Figure 1).

However, the increasing cost of labor, machinery and fuel

may see a shift to greater use of herbicides and reduced

tillage in the future.

m a n a G e m e n t o f W e e d s

inteGrated manaGement

In the upland situation in Cambodia, water is often the

most critical factor reducing potential crop yield. Crops can

fail because of drought, especially in the early wet season

when rainfall is variable and unreliable. Good weed control

is essential under these conditions, especially before sowing,

to avoid the depletion of sub-soil moisture by competing

weeds.

Farmers are encouraged to use an integrated weed

management approach that combines all available options.

The aim should be to keep the weed numbers low andprevent the weeds from producing seeds throughout the

cropping cycle. However, many of the weeds in the upland

situation have a useful purpose for animal fodder or for

use as vegetables. Therefore, a balance may be required in

weed management to provide for these uses without greatly

reducing the profitability of the upland crop.

Figure 1. Traditional practice of plough


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The farmer should be thinking about how to manage

the weeds well before the crop is sown. This means

preventing weeds from setting seeds in the previous crop

and controlling weeds around the edge of the field, along

waterways and in adjacent non-cropped areas. Special

attention needs to be given to weeds such as nut grass

(kravanh chruk) that grow from underground tubers orrhizomes. This weed is difficult to control by cultivation,

and plants regrow from underground parts after the crop

is sown. Some of the practices that can be used in an

integrated weed management program are described below.

feedinG to liVestocK

Weedsespecially annual grasses, can be grazed or hand

harvested to feed to livestock (Figure 2).

However, it is important that the weeds are prevented

from producing seeds. Note that there may be a trade-off

to consider between the amount of soil water used by

the weeds and the soil water required by the crop. This is

important in the early wet season, when the presence of

stored soil water pre-sowing could prevent crop failure from

drought.

Good aGronomic practice

Good agronomic practice includes making sure the crop

seed for sowing is clean and free of weed seeds. Seed forsowing should have high germination percentage and

seedling vigour. Faster-growing vigorous seedlings are more

competitive with weeds. The crop plant population must be

optimal for the conditions. Recommended seeding rates are

usually lower for rainfed than for irrigated situationsthis

is especially important for crops such as maize, which have a

determinate growth habit.

Figure 2. Grass weeds harvested from a

for livestock feeding. Late removal of g

potential of the crop.


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timely Weed control

Traditionally, cultivation has served the dual purpose of

killing weeds and preparing a seedbed. However, cultivation

can also reduce the amount of soil water available tothe crop. Some upland soil types such as Labanseak and

Kampong Siem are friable and self-mulching and may

require little or no cultivation to prepare a seed bed. In

this case, pre-sowing cultivation can be replaced by an

application of a herbicide such as glyphosate, which controls

the weeds without loss of soil moisture. Cultivation is also

less effective in controlling weeds when the soil is wet, and

herbicides could also be used as an alternative under these

conditions. Keeping the residue from the previous crop canhelp suppress weeds (Figure 3).

Figure 3. Weeds can be suppressed by p

Here cotton has been planted into a mu

GrazinG or bUrninG

Heavy grazing or burning is often used to control weeds and

to make conditions easier for ploughing (Figure 4). These

practices have the disadvantage of reducing the groundcover, increasing soil surface temperature and reducing

soil moisture. Burning also reduces soil organic matter and

causes soil degradation and erosion. Preserving soil residues

and even adding mulch such as rice straw can reduce the

emergence of weeds, conserve soil moisture, and reduce the

soil temperature.

Figure 4. Crop residues should be sprea

burned. Ground cover preserves soil mo


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important Weeds

In this book we have included 70 plant species that occur

in upland crop areas. Not all of these are considered to be

serious weeds in current upland cropping systems. However,

some of these plants have the potential to become weeds

under changed agricultural practices for example, a

change to reduced tillage or to plantation crops. The weedslisted in Table 1 are considered to be the most important in

the current cropping system, which is based on cultivation

and hand-weeding. These weeds are a problem because

they are adapted to cultivated conditions and disturbed

soil. These conditions provide a seedbed and mineralised

nitrogen and favour rapid germination and growth of annual

weeds. Species with underground rhizomes or tubers, such

as Cyperus rotundus, are difficult to control because they can

regrow rapidly after hoeing. Species with fleshy stems, suchas Commelina benghalensis, are difficult to control because

the chopped stems produce roots and rapidly regrow.

Table 1. Important weeds of current upland cropping systems in Cambodia

Grasses, sedGes broad leaVed Weeds

Brachiaria reptans,s K Amaranthus spp., p b, p du

Cynodon dactylon, s c c Boerhavia diffusa, p t

Cyperus rotundus, Kv cuk Cleome viscosa, m K

Dactyloctenium aegyptium, s cug K Commelina benghalensis, s t

Digitaria adscendens, s sk m Euphorbia heterophylla, tuk d K t

Echinochloa colona, s bk K Physalis angulata, pg p s

Eleusine indica, s sg Trianthema portulacastrum, cug Kg


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identification of Weeds

Weed species differ in their responses to management

practices because they have different life cycles and nutrient

requirements and different modes of reproduction. They

also vary in their responses to cultivation and susceptibility

to herbicides. It is therefore important for the adviser

and farmer to be able to recognize different weed species

and to understand their weaknesses. This field guide for

identification of weeds of upland crops in Cambodia has

been produced for this purpose.

W e e d d e s c r i p t i o n s

hoW to Use this GUide

The order of presentation of plant species in this book is

alphabetical according to family, genus and species. A plant

family (e.g. Euphorbiaceae) contains a number of plants,

all of which have one or more features in common. The

family is split into a number of genera (e.g. Chamaesyce,

Euphorbia,Jatropha), with the plants in these generic

groups having further common characteristics. Each of the

genera (genus) comprises one or more species, each with

its own distinguishing or specific name (e.g. Chamaesyce

hirta, Euphorbia heterophylla, Jatropha gossypiifolia). Thesenames are distinct from each other and from those of every

other plant species. The guide also includes, where available,

the Khmer name for the weed.


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distribUtion

Common along roadsides and wasteland in northwestCambodia.

description and bioloGy

Herb with tuberous roots. Branched erect stems to 50 cm tall.Leaves mostly basal, finely hairy, ovate to oblong,46 1.52.5 cm. Purple tubular flowers, 46 cm long,1215 mm wide. Reproduces from seed.

aGricUltUral importance

Does not appear to invade upland crop fields.

reference: 1

a c

Ru el l i a tu b erosa (K bk)


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distribUtion

Prefers dry conditions. Distributed in upland crop fields, on

roadsides and in waste areas throughout Cambodia.


Prostrate, somewhat succulent annual or perennial herb withovate green leaves and small white-pink flowers hidden amongthe leaves. Flowers for most of the year. Reproduces from seed.


This plant can be a serious weed in upland cropsreference: 2

T ri an th ema portu l acastru m (cug Kg p)


es Ap If


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distribUtion

Found in wastelands, along roadsides, and in pastures andupland crop fields.


Erect herb from 0.52 m tall. Flowers small an d green. Fruitis a prickly burr 2.52.8 mm long, easily detached. Bractsaround seed are turned down and stick to animals and clothing.Reproduces by seed.


Occurs along roadsides, in waste areas, pastures and plantationcrops, and occasionally in upland crops. Often infests the edges

of fields. Can grow on a wide range of soil types.

reference: 3

A ch ryan th es aspera (a Ku) e

a m a r


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A l tern an th era sessi l i s (cug bgkg)


a m a r

distribUtion

Found mainly on the banks of streams and ponds, along the

sides of paddies, and in shallow waterways. Also occurs inupland crops in the rainy season.


Creeping annual or short-lived perennial. Flower heads are 57cm long, rounded or oblong, and borne in leaf axils. Spread bypieces in mud attached to machinery, and by flood.


Prefers places with high humidity and is often found in and nearponds, canals and reservoirs. May be found in swamps, shallowditches, and fallow rice fields. Mainly a weed of paddy andupland rice but can also occur in upland crops.

reference: 2, 3

A th i (p b )


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distribUtion

Prefers dry conditions and is found along roadsides and inwastelands and upland crops.


Erect annual that has a pair of sharp spines at the base of eachleaf. The plant has a striped reddish stem. Flower heads aregreen. Propagates with seeds that have a long life in the soil.Seeds are dispersed by wind and water.


Grows well in fields when soil moisture is low, and prefers soilshigh in organic matter and available nitrogen. The leaves are

used as a vegetable in Cambodia.

reference: 2, 7

Amaranthus spinosus (p b)

a m a r


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distribUtion

Prefers dry conditions and is found in wastelands, on roadsides

and in upland crops.


Prostrate to erect branched annual herb, 30 to 80 cm tall. Stemsare grooved and can be reddish. Flower spikes are green topurplish, 515 cm long. Reproduces by seed.


Competitive weed in upland crops. Occurs on a wide range of soiltypes and responds to high fertility. Germination is stimulatedby application of nitrogenous fertiliser. Leaves are used as avegetable.

reference: 2, 3

Amaranthus viridus (p dug)


a m a r

Cel osi a argen tea (s p p p)

e


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distribUtion

Occurs along roadsides and in wasteland, young rubberplantations and upland crop fields.


Annual herb. Stems erect, branched, smooth, strongly ribbed,and up to 150 cm tall. Leaves are long and slender with a sharpend, upper ones with a slight stalk. Flower heads are pink. Fruitsare egg-shaped. Seeds are lens-shaped, black and 1.31.5 mmlong. Propagated by seeds.


If left uncontrolled, this weed can compete strongly with the

crop, particularly soybean and mungbean.

reference: 1

Cel osi a argen tea (s p, p p) e

a m a r


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distribUtion

Occurs along roadsides and in wasteland and upland crop fields.

Occasional to common in pasture and in sunny, disturbed places.


Creeping herb with stems commonly 115 cm long. Leavesorbicular-cordate or kidney shaped, with toothed margins,25 cm long and usually broader than long. Flower 17 cm long,secondary umbels of 24 flowers. Petals pinkish-purple, 1 mmwide, stamens shorter, fruit 45 mm broad and 3 mm high.


Common in upland crop fields in Battambang but not a major

competitive plant.

reference: 1

Cen tel l a asi ati ca (V tk K)


vl

Ageratum conzoides (Kg K)


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distribUtion

Commonly found in upland crop lands throughout Cambodia.


Annual herb. Stems erect, branching up to 80 cm tall. Leavesopposite, hairy, soft, ovate, sub-cordate, with serrated margin.Flower heads terminal. Flowers white to violet. Propagated byseed.


Occurs in upland crop fields but is not a significant problemunder cultivated conditions.

reference: 2, 7

Ageratum conzoides (Kg K)

a


23/90

distribUtion

Prefers well drained soils. Found on roadsides and in wastelands,

pastures, orchards and plantations.


Perennial shrub up to 3 m tall. Stems branched, hairy and round.Leaves, opposite, ovate-deltoid, hairy with serrate margin, 8 to10 cm long. Flowers pale blue in clusters. Reproduces by seed.


Invades clearings but does not survive after the forest orplantation canopy closes in. Not an important weed ofcultivation or annual upland crops.

reference: 2, 7

Ch romol aen a odorata (tu K)


a

Ecl i pta al b a (mk cg)


24/90

distribUtion

Prefers both wet and dry conditions. Found in paddies alongwaterways and in upland crop areas.


Annual herb. Stems erect or prostrate, up to 50 cm tall. Leavessimple, opposite, lanceolate to elliptic, sub-entire, hairy on bothsides. Flower is axillary or terminal and about 1 cm in diameter,white with a tubular green calyx. Reproduces by seed.


Usually found in poorly drained areas. Not an important weed inupland crop areas.

reference: 2, 7

Ecl i pta al b a (mk cg)

a


25/90

distribUtion

Occurs along roadsides and on wasteland in upland areas.


Low, spreading annual or perennial herb, 0.61.2 m tall,sometimes woody toward base, often purplish throughout;stems branched, sparsely hairy. Leaves often bluish or grayishwhen fresh, alternate or opposite, somewhat fleshy, oblongto elliptic or ovate, 29 cm long, 1.54 cm wide. Flowerheads stout and stiff, 1550 cm long, up to 7 mm in diameter.Flowers pale blue, 811 mm long.


Not observed as a weed in upland crops.

reference: 1

Spi l an th es pan i cu l ata (du c e)


a

Synedrella nodiflora (s Kk)


26/90

distribUtion

Weed in upland fields and on roadsides and wastelands.


Annual herb. Stems erect, sub-angular, up to 90 cm tall. Leavesopposite, elliptic or ovate, acute apex, crenate-serrate. Flowerhead axillary and sessile, petals yellow. Propagates by seed.


This plant has the potential to compete with upland crops if itis not controlled.

reference: 1

Synedrella nodiflora (s Kk)

a


27/90

distribUtion

Prefers upland conditions. Distributed in upland crops and on

roadsides and wastelands.


Semi-prostrate annual or short-lived perennial with stems upto 50 cm long. A weed of pastures and a wide range of annualand perennial crops. Seeds are carried by wind over a widerange. Reproduces from seed, stem spread and persistent roots.


The Tridaxplants found in upland fields often survive the dr yseason. They are commonly seen in the early wet season but inannual cropping systems are usually controlled by ploughing.

reference: 2, 3

T ri dax procu mb en s


a s t

Vern on i a ci n erea (su ru)

\sIp


28/90

distribUtion

Found in upland crop areas and wastelands and on roadsides.


Annual herb, stems erect, branched, hairy, up to 80 cm tall.

Leaves ovate to obovate and hairy beneath, 1.02.5 cm wideand 2.04.0 cm long. Flower heads widely branched, flowersnumerous, purple. Reproduces by seed.


Not a significant weed in upland cropping systems.

reference: 2

Vern on i a ci n erea (su ru) \sp

a


29/90

distribUtion

Commonly found in wastelands and on roadsides. Does not

appear to be common in upland crop fields.


Annual herb. Stems branched and sparsely hairy, 15 to 50 cmtall. Leaves ovate, 5 to 7 cm long. Flower is a curved terminalspike 5 to 15 cm long. Reproduces by seed.


Does not appear to be a threat to upland cropping systems.

reference: 2, 7

Hel i otropi u m i n di cu m (p d)


e

b o r

Cl eome gyn an dra (m)


30/90

gy ( )

c a p

distribUtion

Occurs in dry areas, especially along roadsides and in pastures.Present in upland crop fields.


Annual herb 0.51.5 m tall, stems unbranched to sparselybranched, glandular-hairy. Leaflets 37, oblanceolateto rhombic, 27.5 cm long, 13.8 cm wide, marginsserrulate to denticulate, stems 39 cm long. Flowersin racemes, subtended by trifoliate, sessile bracts;petals white with a long claw, 12 cm long. Capsulesnarrowly cylindrical, 311 cm long, 45 mm indiameter. S eeds numerous.


Occurs in upland crop fields but is not a majorcompetitive weed.

reference: 1


31/90

distribUtion

Occurs in upland crop fields and on roadsides and wasteland.


Annual herb to 1 m high. Stems angular with scattered softbristles. Leaves with 3 ovate to spear-shaped leaflets (25 cmlong). Flowers are solitary in the leaf axils, with 4 petals 9 to12 mm long on the upper side. The flowers are red, turning pinkwith age. Spread by seed, water, farm machinery, ants.


This species is a weed of upland crops and also an environmentalweed. It is naturalised in South-East Asia. It grows rapidly andneeds to be removed from upland crops. A range of soil andfoliar applied herbicides are effective on Cleome spp.

reference: 6

Cl eome ru ti dosperma (m K, p K)


c a p p a

Cl eome vi scosa (m K, p lug)


32/90

distribUtion

Found in paddies as well as upland crop fields and wasteland.


Erect annual herb 20140 cm tall, with 3 or 5 leaflets. Flowers

are yellow with 4 petals. The fruit is pod-like, slender and34 cm long. Propagation is by sticky seeds.


Occurs in cultivated fields and along roadsides. In Cambodia itis known as ghost vegetable because it grows on graves.

reference: 11

g

c a p p


33/90

distribUtion

Prefers wet conditions. Found in paddies and along waterways.


Perennial herb. Stems succulent, creeping, ascending androoting at the lower nodes. Leaves linear-lanceolate, withtubular sheath with hairs. Flowers solitary and axillary, with 3petals, purple to violet. Reproduces vegetatively and by seed.


This is a small weed with a sprawling, creeping habit. It occurs in

low-lying upland crop fields.

reference: 2

Cyan oti s axi l l ari s (cu t)


c o m m

Commel i n a b en gh al en si s (s t)


34/90

distribUtion

Prefers moist conditions and occurs in upland crops in Cambodia.


Fleshy, herbaceous, creeping annual or perennial plant. The

stems, which grow along the ground, are fleshy, hairy andbranched and 3050 cm long, with roots at the nodes. Theflowers are violet to blue.


This plant has a sprawling, creeping habit and has the ability toroot readily at the nodes, thus making it an important weed ofcultivated crops. It has a high moisture content, and although ithas little value as a livestock feed it is fed to pigs in Cambodia.

reference: 2, 3, 7

c o m m


35/90

distribUtion

Found in thickets, roadsides, waste places, and cultivated areas.


Herbs perennial, twining, with a tuberous root. Stems to 5 m.Leaf blade palmately 5-parted to base. Inflorescences with 1 orseveral flowers. Corolla pink, purple, or reddish purple, with adarker center, rarely white. Reproduces by seed.


Not commonly found in upland fields.

reference: 8

Ipomoea cai ri ca (p Kuug K)


edI

c o n V o

Ipomoea ob scu ra (V mu l)


36/90

distribUtion

Found in upland cultivated crops, grasslands, roadsides andwaste places.


An annual or perennial herb with twining stems 13 m long.Stems around 3 mm thick, leaves heart-shaped and 48 cmlong. Most species ofIpomoea produce seeds within globularcapsules. Seed dispersal is by wind ac tion and gravity.


This species is common on roadsides and along the edges ofupland crop fields. However, it does not appear to be as serious aweed in upland crops as I. triloba.

reference: 8

c o n V o


37/90

distribUtion

Found in upland cultivated crops and grasslands and on

roadsides and wasteland.


Annual herb with twining stems 13 m long. Stems around3 mm thick, leaves 3-lobed a nd 411 cm long. The flower isfive-lobed, funnel-shaped and pink or pale red. Flowers closeafter noon. Little is known about the biology of this plant. Itreproduces by seed.

aGricUltUral importanceIt can grow over other vegetation in farmers fields and has thecapacity to smother crops. It has been recorded as a weed inmaize, peanuts, upland rice and sugarcane.

reference: 3, 8

Ipomoea tri l ob a (s cu)


c o n V o

Trichosanthes cucumerina (suk b)


38/90

c U c

distribUtion

Occurs along roadsides, in wastelands, and on the margins ofupland crop fields.


Climbing, herbaceous vine 56 m. Stems green, 4-angled, hairy.Leaves hairy on both surfaces, rounded, 714 cmlong and broad, and 35-lobed; base is broadlyheart-shaped. Male flower heads have 6 to 15 flowers.Petals white, about 1.3 cm long. Female flowers occursingly in the axils of the leaves. The fruit is ellipsoid,34.5 cm long, 2.53 cm in diameter, green andmottled, with longitudinal gray stripes when young,and orange-red when mature.


Not a major weed of upland cropping systems.

reference: 12


39/90

Cyperu s rotu n du s (Kv cuk)


e

c

distribUtion

Prefers dry conditions; grows in wastelands and upland crop

fields. Also tolerates moist soil conditions.


Herbaceous, perennial sedge with rhizomes and stolons. Grows to3070 cm tall. Leaves 520 cm long. Flower head has38 unequal rays. Spikelets flattened without a stalkand 13 cm long. Rhizomes form chains of tuberousbulbs up to 25 mm that produce shoots and roots.

aGricUltUral importanceAlthough a relatively small plant, C. rotunduscompetes strongly with crop plants. However, it doesnot tolerate shading and its growth can be slowedby application of 2,4-D in a grass pasture or mulchcrop (Stephanie Boulakia, Centre de Co-operationInternationale en Recherch pour de Developmentpers. comm.).

reference: 2, 7

Acalypha indica (pk c)


40/90

distribUtion

Found along roadsides and in upland crop fields.


Annual weedy herb up to 50 cm. Contact with the sap or latex of

this member of the spurge family can cause an acute dermatitis.


Not seen as an important weed of upland cropping systems.

reference: 13

e U p h

es


41/90

distribUtion

Occurs along roadsides, on wasteland, and in upland crop fields.


Sometimes used in herbal medicine. Distinguishing features arethe milky sap of the stem and the sometimes purple blotchedleaves with toothed margins. Leaves are opposite, toothed, and15 cm long and 0.52.5 cm wide. Seeds can be produced in amonth or less, and dense stands can develop in a short time. Theplant flowers year round.

aGricUltUral importanceAn early coloniser of bare ground, especially under damp orirrigated conditions. The plant has slightly poisonous propertiesand is regarded as useless as livestock feed.

reference: 2, 3, 7

Ch amaesyce h i rta (tuk d K tu)


es

e U p h

Eu ph orb i a h eteroph yl l a (tuk d K t)


42/90

distribUtion

Found in upland crop fields and wastelands.


Annual weed with latex throughout. The stem is round and

hollow and repeatedly forked towards the apex. Leaves are510 cm long and whitish beneath. The fruit is a 3-lobedcapsule 3.55.0 mm in diameter. This weed has a short lifecycle and can complete up to 4 generations a year.


Grows on a wide range of soils, mainly during the rainy season.It frequently infests plantation crops, cotton, soybean andmaize.

reference: 2, 3

e U p h

es


43/90

distribUtion

Found on roadsides and wasteland and in upland crop fields.


Annual herb. Stems are branched, spreading, hairy and reddish.Leaves in 2 opposite rows. Flowers axillary, pink to purplish.Fruit is a capsule that is hair y, triangular and green. Has a milkysap. Reproduces by seed.


Occurs in upland crop fields but is unlikely to be a

competitive weed.

reference: 2

Eu ph orb i a th ymi fol i a


e U p h

es

Jatropha curcas (lg Kvg)


44/90

e U p h

distribUtion

Common along roadsides, fencelines and the edges ofupland fields.


Small tree, to 5 m; deciduous leaves are wide-ovate to heart-like, to 25 15 cm, 35-angled or lobed; stalk to 15 cm. Flowersin terminal clusters; male calyx with 5 lobes to 4 mm, 5 petals,6 mm, pale greenish to yellowish-white, 810 stamens; femalecalyx 5 lobes 69 mm, petals similar to male, stigma with twotips. Fruit ovoid, 4 3 cm, ripens yellowish then dries brown andsplits. Three seeds, black, ovoid, 20 12 9 mm, surface hardand rough.

aGricUltUral importancePlanted as a living fence to keep out animals and provideshade. Seeds have a pleasant taste but contain an oil that causesvomiting and purging. This species has potential for biofuelproduction in Cambodia.

reference: 10


45/90

Ph yl l an th u s n i ru ri (bk p)


46/90

distribUtion

Upland crop areas, wasteland and roadsides.


Small, erect, annual herb that grows to 3040 cm high. Leaves

are pinnate with leaflets oblong, entire and sessile. Flowersare on short stalks at the bases of leaves and are white or palegreen. Fruit is a capsule, rounded and smooth. Reproduces byseed.


Although this species occurs in upland fields, it is not consideredto be a major competitive weed of upland crops.

reference: 2, 3

e U p h


47/90

distribUtion

Prefers dry conditions; found in upland crop fields, wastelandsand pastures.


Perennial shrub. Stems erect, branched, hair y. Leaves pinnatelycompound, with oblong leaflets 710 mm long. Pinkflowers with red centres on racemes. Pods oblong,curved, and 23 cm long. Reproduces by seed.


Not a significant weed of cultivated fields.

reference: 2

A esch yn omen e ameri can a (s ah)


A l ysi carpu s mon i l i fer (du s o)

edI


48/90

distribUtion

Along roadsides, on grazing land and in upland fields.


Low-growing, branched, annual or perennial herb, 515 cm tall.

Leaves simple, ovate, elliptical or lanceolate, cordate at the base,2.57.5 cm long, hairy beneath. Flower heads 115 cm long,flowers red. Pods 35-jointed, 12 cm long. Reproduces by seed.


Introduced forage plant. Could be a useful component oflong-term and short-term pastures in low- to medium-rainfallareas, especially under heavy grazing.

reference: 4


49/90

distribUtion

Occurs along roadsides, on wasteland and grave sites, and inupland crop fields.


An erect annual herb with leathery compounded ovate-acuminate leaves growing up to 2 m tall. Flowers are yellow. Theseed pods are dark brown and curve slightly upward. The seedsare olive-brown and flattened on both ends.


Occurs in upland areas but is not a serious weed of cultivatedannual crops.

reference: 1

Cassi a occi den tal i s (sk Ku)



50/90


51/90

distribUtion

Occurs along roadsides and in wasteland and upland crop fields.


Perennial climbing herb that roots at nodes. Leaves trifoliolate,leaflets ovate to orbicular, about 3 cm long and 1.32 cm broad,shortly acuminate and finely pubescent. Three to five lilac tobluish-violet flowers on axillary racemes. Pod 13 cm long and56 mm broad, slightly bent and beaked, containing up to 15seeds. Reproduces by seed.

aGricUltUral importanceIntroduced pasture plant normally grown in a mixture witha grass for cut-and-carry. Potential also as soil cover. Minorpotential as a weed in upland crops.

reference: 4

Cen trosema pu b escen s (Ku yu)



52/90


53/90

Mimosa invisa (p K d, b s)


54/90

distribUtion

Prefers moist conditions. Distributed on wasteland and inplantation crop lands. Occurs along roadsides and on themargins of upland crop fields.


Perennial shrub. Stems erect and climbing, 1.02.0 m tall,characterized by sharp recurved spines, hai ry. Leaves bipinnate,moderately sensitive to touch, 1530 pairs. Flower head pink.Pods spiny. Reproduces by seed.


Occurs around the edges of upland fields and in live fences butdoes not usually occur in cultivated fields.

reference: 2, 7

Mi i (p K y k)

RB


55/90

distribUtion

Prefers wet and swampy conditions. Widely distributed alongthe Mekong and Tonle Sap.


Perennial woody shrub, rapid growing. Stems strong, withspines, and 24 m tall. Leaves bipinnate, more than 20 cmlong. Flowers pink. Pods hairy, slightly curved, 510 cm long.Reproduces by seed.


This is a major weed of lowland areas and is a significantconstraint to agricultural development in these areas.

reference: 2

Mimosa pigra (p K yk)


RB

Mimosa pudica (p K)

distribUtion


56/90

distribUtion

Distributed mainly along roadsides and on wasteland. Alsooccurs in upland crop fields.


Much-branched perennial herb. Sometimes behaves as anannual. Upright to trailing growth, 20100 cm high. Stemsstiff with scattered prickles. Leaves are bipinnate with one ortwo compound leaflets. Herbaceous and woody. Reproduces byseeds, which can be transported on a nimals, clothing etc. Canstand considerable shading.


Common weed in upland crops, including some vegetable

crops and plantation crops, and pastures. The thorny stemsmake grazing difficult. The thorns also present difficultieswhere hand-weeding of crops is practised.

reference: 2, 7

M ti l i t (V K t ) v


57/90

Macropti l i u m atropu rpu reu m (V Kuu tu)


vdistribUtion

Roadsides, wasteland, grazing lands and upland crop fields.


Perennial herb with trailing and twining stems. Leavestrifoliate, flower head a raceme with 612 flowers on a shortrachis, stem 1030 cm long. Flower deep purple with reddishtinge near base. Pods straight, beaked, hairy, 510 cm long,35 mm in diameter. Pods shatter violently when ripe.


Legume introduced for grazing. Can also be used forcut-and-carry, although the twining habit can make har vestingdifficult. Can be used as a forage crop sown with upland rice.Could also be used as a nitrogen-fixing mulch crop beforemaize. Because of the hard seeds, plants could emerge insubsequent upland crops.

reference: 4

distribUtion

Hypti s su avi ol en s (mk tu)

edI


58/90

distribUtion

Plantation crop areas, roadsides, wasteland and pastures.


Annual herb. Stems hairy, erect, branched and 50150 cm tall.

Leaves ovate, 49 cm long. Purplish-blue flowers in clusters of3 or 4 at the bases of leaves. Reproduces by seed.


This plant has been observed along roadsides but not as aweed in upland crops.

reference: 1

A b el mosch u s mosch atu s (mu puk p)


59/90

distribUtion

Occurs in open and disturbed areas and marshes. Naturalisedin plantations, rice fields, and clearings, and also occurs along

trails and on the edges of forests.


Herb or under-shrub to 1.5 m tall. Leaves variable inshape and size. Flowers axillary, solitary, mostly yellowand dark purple at base. Propagates by seed.


Not a major weed of cultivated annual upland crops.reference: 1

A b el mosch u s mosch atu s (mu puk p)


distribUtion

Abutilon indicum (t K)


60/90

distribUtion

Found on wasteland, along roadsides, and in upland crop fields.


Perennial herb with branched hairy stems. Leaves are heart-

shaped, with toothed margins. Flowers are yellow with stemjointed above the middle. The fruit is a capsule anddensely hairy with distinct ribs. Reproduces by seed.


Not a major weed of upland crop fields.

reference: 2


61/90

Sida acuta (Kg b s)

distribUtion


62/90

distribUtion

Prefers dry and sandy soil conditions. Distributed in upland cropareas, on roadsides, and in wasteland and pastures.


Small, erect, much-branched perennial shrub or herb 30100 cmhigh. Strong taproot. Capsules split into 1-seeded segments;the awns on these can stick to animals and clothing and aiddispersal. Reproduces by seed.


Very competitive. Grows well in many soils, including heav yclays. Can tolerate wet as well as dry zones. Without cultivationor herbicides it is very difficult to control because of the tough

fibrous stems and taproot. Continued ploughing can kill theweed, but the deep taproot makes cultivation difficult. Notpalatable to livestock.

reference: 2, 7

Sida rhombifolia (Kg b s n) k


63/90

Sida rhombifolia (Kg b s n)


k

distribUtion

Prefers dry and sandy soil conditions. Distributed in upland cropareas, on roadsides, and in wasteland and pastures.


Small, erect, branched perennial herb 30100 cm high. Leavesare brighter green, longer and narrower than in S. acuta. Capsulessplit into one-seeded segments. The awns on these can stick toanimals and clothing and aid dispersal. Reproduces by seed.


Very competitive. Grows well in many soils, including heav yclays. Can tolerate wet as well as dry zones. Without cultivationor herbicides it is very difficult to control because of the toughfibrous stems and taproot. Continued ploughing can kill theweed, but the deep taproot makes cultivation difficult. Notpalatable to livestock.

reference: 2, 7

distribUtion

Uren a l ob ata (a cuk)


64/90

Invades disturbed areas: a weed of wasteland, roadsides andpastures.


Erect shrub to 1 m tall. Leaves palmately lobed, 48 cm long,usually 5-lobed, or angled. Flowers pinkish-violet,about 1 cm broad. Fruit hairy and with hooked bristles.


A weed mainly in canefields, pastures, clearings andgrassland.

reference: 1

Boerh avi a di ffu sa (p t)


65/90

Boerh avi a di ffu sa (p t)

WEEDS OF UPLAND CROPS IN CAMBODIA n y c

distribUtion

Commonly found on wasteland and roadsides, and in pasturesand upland crop fields.


Spreading, loosely branched annual or perennial herb. Prostrateinitially, then upright from 40150 cm. Stems red topurple, with few hairs. Leaves dark green to purple,15 cm long, with wavy or lobed margins. Flowerswhite to pink, 1.52.5 mm long. Reproduces by seed.


A common weed in cultivated fields, perennial cropsand pastures, and on roadsides and wastelands. Theplant has a thickened taproot and can persist throughthe dry season. If left uncontrolled in maize or soybeanfields, it can reduce yields by 70% to 80%.

reference: 3, 2

distribUtion

Passi f l ora foeti da (sv m p)


66/90

Found in upland cultivated areas, on roadsides and wasteland,and along fences.


Perennial herb. Stems hairy, climbing, trailing up to 6.0 m long.Leaves alternate, three-lobed. Solitary flowers, whitewith purple base, found at the bases of leaves. Fruit isenclosed in a netted green calyx. Reproduces by seed.


This plant is common in upland areas along roadsides,but because of its perennial nature it is not likely to bea serious weed in annual cropping systems.

reference: 2, 3

p a s s

Brach i ari a mu ti ca (s bg)


67/90

( g)


distribUtion

Prefers poorly drained soils. Found in paddies and alongwatercourses and does not tolerate extended dry conditions.


Creeping perennial grass with long, coarse stolons up to 5.0m long, very hairy. Stems lie on the ground and have soft,moderately hairy leaves up to 20 mm wide and 30 cm long.Stolons and branches root readily at nodes.


Adapted to a wide range of soil types. Suited to poorly drainedland, but will also grow on free-draining soils. Can become aproblem in wetland areas that are not grazed: sugarcane fields,irrigation ditches and drains. Cut and fed to cattle in Cambodia.

reference: 2, 3, 7


68/90

Cyn odon dactyl on (s c c)


69/90

distribUtion

Perennial grass common along roadsides and in pastures,wastelands and upland crops in Cambodia.


Fine-leaved, prostrate perennial grass. It roots at the nodes andalso has underground stolons that enable it to spread rapidly byvegetative means. Propagates mainly by vegetative means andis a sparse seed producer; therefore, control measures need tofocus on preventing spread by animals, machinery etc.


A weed in many upland crops. However, it is also a useful pastureand can be used to prevent soil erosion. Adapted to a wide rangeof soil pH and moisture conditions but prefers medium to heavysoil types.

reference: 7

y y ( )


Dactyl octen i u m aegypti u m (s cug K)

distribUtion


70/90

Prefers dry conditions and can survive the dry season inCambodia. Found in upland crops and wasteland and is widelydistributed in Cambodia.


Herbaceous annual grass 50 to 150 cm tall, with soft, slightlysucculent leaves. May contain cyanide compounds and istherefore a danger to stock at certain times. One of the bestgrazing grasses in semi-arid areas, but it dries out with the onsetof the dry season. Stems are round, erect or trailing, solid andhairless.


This plant is a troublesome weed of upland crops such as maize,cotton, sugarcane and peanuts. A range of herbicides areavailable for its control.

reference: 2, 7

Di gi tari a adscen den s (s sk m)


71/90

distribUtion

Prefers upland conditions. Found in wasteland and crop landsand occurs throughout Cambodia.


Annual grass 30 to 50 cm high. Leaves linear-lanceolate, withhairs at the sheath and blade mouth. Seed head is a spike with5 to 8 fingers, each about 10 cm long. Palatable when young.Flowers all year round. Often grows rapidly when other plantsare under temperature or water stress. Tillers root at nodes.


Difficult to control by ploughing when established. Deceptivelycompetitive for moisture and nutrients. The grass is collected tomake nests for chickens.

reference: 2, 3


Ech i n och l oa col on a (s bk K, K Ku) esAEbkkdistribUtion


72/90

Prefers both moist and dry lands. Found in direct-seeded riceand in upland crop fields. Widely distributed in Cambodia.


Annual grass. Tufted, erect and jointed, often flat on the ground,

and 3060 cm high. Reddish-purple or green. Leaves linear and1015 cm long. Seed head is a panicle with 310 branches 515cm long. Propagates by seed. A single plant may produce asmany as 40 000 seeds.


Grows in wet conditions. The source of infestation can be impurecrop seed. Land preparation, planting date, planting method,

crop grown, plant spacing, and fertiliser management can all beused for integrated management to control this weed.

reference: 2

El eu si n e i n di ca (s sg)


73/90


distribUtion

Prefers soils of low moisture. Found on wasteland and roadsidesand in upland crop fields. Tolerates traffic and compaction.


An annual tufted grass, stem erect or lying flat at the base, upto 80 cm tall. Leaf blade 1030 cm long, sheath 69 cm long,flattened laterally, with a few long hairs at the junction withthe blade. Grows well in hot areas as well as in dry conditions.Reproduces by seed.


Grows in a wide range of crops. Found in waste areas becauseof its tolerance to drought. Normally controlled by ploughingand land preparation. Is also well controlled by several selectiveherbicides, as well as by knockdown herbicides.

reference: 2, 7

Imperata cyl i n dri ca (suv Kg)

distribUtion

G b th d d t il Di t ib t d i t l d d


74/90

Grows on both dry and wet soils. Distributed in wasteland andopen forests and sometimes in upland crop fields.


An erect perennial grass. Robust, hairy at the nodes, and

0.51.0 m high. Reproduces by seed and rhizomes. Flowering isusually initiated by stress, such as burning, cutting or drought.Numerous seeds are produced and can be dispersed by wind overlong distances. Tolerant of burning; rapid regrowth occurs fromthe rhizomes, which are protected by the soil.


Common weed of rubber and tree crops. Occurs in upland cropfields, especially during the dry season, but does not appear totolerate ploughing.

reference: 2, 7

Sorghum halepense (tg)


75/90


distribUtion

Occurs on roadsides and occasionally in crops in Battambang.Appears to be spreading into Cambodia along roads in the

north-west.


Erect perennial to 1.5 m tall, with strong rhizomes.Nodes have short hairs. Leaves usually 11.5 cmwide, the midrib prominent. Seed heads 1525cm long; spikelets 5 mm long. Plants develop longrhizomes bearing buds, which germinate readily. Seedproduction is variable and depends on environmental

factors.


This species could be a serious weed of cultivation if itwere to become established in upland crop fields.

reference: 1, 7

Portu l aca ol eracea (K cu)

distribUtion

Occurs in upland crop fields and vegetable crops and on


76/90

p o r t

Occurs in upland crop fields and vegetable crops and onwasteland.


Prostrate, fleshy, succulent annual plant that is able to tolerate

poor, compacted soils and drought. Stems are usually purple-redand may root at the lower nodes. These many branched stemsreach up to 60 cm long and grow in a prostrate fashion to formmats. Reproduces by seed.


Once established, it is drought tolerant. To control withoutherbicides, maintain a dense and healthy cover by using propercultural practices. If mechanically removed, destroy the stems,as they may root in open soil. Several post-emergent herbicidesgive satisfactory control.

reference: 2


77/90

distribUtion

Occurs on open land and roadsides and in upland crop fields

Hedyoti s di ffu sa (K c)


78/90

Occurs on open land and roadsides and in upland crop fields.


Slender, spreading or ascending, more or less branched annualherb, reaching a length or 50 cm or less. Leaves linear and

13 cm long. Flowers white, 3 mm long and occurring singly inthe axil of the leaf. Fruit is a capsule about 4 mm long.


Not a major weed of upland crop fields.

reference: 2

Ri ch ardi a b rasi l i en si s


79/90

distribUtion

Widespread in upland crops and pastures in north-westCambodia.


Annual herb. Stems spreading on the ground, branched andhairy. Leaves opposite, ovate, thickened. Flowers terminal,white, funnel form. Reproduces by seed.


Prefers dry soil conditions.

reference: 2


distribUtion

Occurs along roadsides and in upland fields, especially in

Cardi ospermu m h al i cacab u m (ag bk)


80/90

Occurs along roadsides and in upland fields, especially inBattambang.


Perennial, herbaceous climber, up to 8 m high. Leaves alternate,

spiral, compound, bipinnate. Leaflet 2862 mm long,1043mm wide, margins serrate, dentate or deeplyincised. Flowers white, 1.55 mm long, in racemes.Fruit, a capsule, n on-fleshy, 1241 mm long, inflated,1544 mm wide.


Forms dense but localised infestations. Can becontrolled by both herbicides and mechanical means.

reference: 5

s a

Ph ysal i s an gu l ata (pg p s) eb :g


81/90


s

distribUtion

Prefers well drained soils. Occurs on roadsides and wastelandand in upland crop fields.


Annual herb with hairy stems, erect, branched and 30 to40 cm tall. Leaves are alternate and have slightly lobedmargin. Flowers are bell-shaped, pale yellow andpurple at the base. Fruit, which is edible, is a roundberry enclosed in the papery sepals. Spread by seeds.


Occurs in upland fields and pastures, on roadsidesand in open woodlands. It prefers disturbed sites. It issusceptible to several herbicides, and deep burial ofthe seeds prevents germination. As well as loweringcrop yields, mature seeds can contaminate grainsamples.

reference: 2, 3

Corch oru s ol i tori u s (K cuv p)

distribUtion

Commonly found in cultivated areas, on wasteland and along


82/90

y , groadsides.


Herbaceous annual growing from 30100 cm, with hairless

leaves. Leaves are 512 cm long and serrated, with the twolower teeth extended into auricles. Flowers, with 5 yellow petals45 mm long, are opposite the leaves. The taproot is highlydeveloped; this helps to provide drought resistance in the earlystages of growth.


This plant has a long history as a food plant and is likely to havebeen used as a vegetable in South East Asia. The genus has alsobeen used for production of jute. As a weed this species is verycompetitive with crops.

reference: 2, 3

Stach ytarph eta i n di ca (s K s-)


83/90

distribUtion

Occurs along roadsides and on wasteland in upland areas.

description and bioloGyLow, spreading annual or perennial herb, 0.61.2 m tall,sometimes woody toward base, often purplish throughout;stems branched, sparsely hairy. Leaves often bluish or grayishwhen fresh, alternate or opposite, somewhat fleshy, oblong toelliptic or ovate, 29 cm long, 1.5 to 4 cm wide. Flower headsstout and stiff, 1550 cm long, up to 7 mm in diameter. Flowerspale blue, 811 mm long.

aGricUltUral importanceNot observed as a weed in upland crops.

reference: 1


V e

distribUtion

Occurs along roadsides, on wasteland, and in upland crop fields.

Cayrati a tri fol i a (V t)


84/90


Vine with smooth, trifoliate leaves generally 3-8 cm long and2-5 cm broad. The leaflets are ovate to deltoid and deeply

toothed. Tendrils arise opposite from each leaf alongthe stem. The flower heads are 610 cm long corymbsor umbels, and the flowers are small and white tocream. The fruits are rounded berries, green turningblack.


This plant occurs around and in upland crop fields butis unlikely to tolerate continuous cultivation.

reference: 14

G l o s s a r y


85/90


Definitions of botanical terms were obtained from the

Shorter Oxford Dictionary.

au

Pointed, tapering to a point.au

Sharp at the end, coming to a point.

agu

With sharp edges or corners.

au

Plant that grows for 1 year or less and reproduces by seed.

ax

The tip, top or pointed end.

aw

Spiny point or process that terminates the grain sheath of

a grass.

ax

The upper angle between a leaf or petiole and the stem from

which it springs.

axSituated in, or growing from, the axil.

b

Any small globular or ovate juicy fruit.

b

Doubly or subordinately pinnate.

b

The leaf of a herb, grass or plant.

bA small modified leaf or scale growing below the calyx of a

plant, or upon the peduncle of a flower.

b

Any short, stiff, pointed or prickly hair.

bu

The underground spheroidal por

lily or similar plant.

buA fruit covered in spines.

cx

The whorl of leaves (sepals), usu

outer covering of a flower while

cu

A dry dehiscent seed vessel cont

cu

Leaf divided into several leafletsc

Heart-shaped.

c

Having an edge that is notched

teeth, or finely scalloped.

G l o s s a r y

c

Shaped like a cylinder or tube.

f

One of the little flowers that make up the composite flower

or spikelet of a grass

lx

A milky liquid that is found in m

Euphorbiaceae and is exuded w


86/90

d

Seed vessels that burst open when ripe.

d

In the shape of a triangle.

d

Leaves with sharp teeth projecting outwards.

du

Having small tooth-like projections.

e

Oval-shaped.

e

Oval.

e

Upright.

or spikelet of a grass.

Gu

In the shape of a sphere or ball.

h

A plant that does not have a woody stem and dies down tothe ground after flowering.

i

Having notches or grooves at the edge.

i

The collective arrangement of flowers on the plant; flower

head.

l

Like a spear-head, narrow and tapering to a point.

Euphorbiaceae, and is exuded w

l

A roundish projecting part.

n

A knob on a root or branch; the the leaves spring.

o

Opposite to lanceolate; tapering

rather than the tip.

og

Elongated in one direction.

ov

Opposite to ovate; tapering to ththe tip.

G l o s s a r y


87/90


ou

Having a rounded or convex surface.

ov

Egg-shaped.p

Pleasant to the palate or taste.

p

In the shape of a palm or hand.

pu

The stalk of a flower or fruit.

p

Remaining alive through a number of years.p

Leaf stalk.

p

Like a feather. A compound leaf with a series of leaflets on

each side of a common petiole.

pg

To reproduce or multiply.

p

Lying flat on the ground.pu

Covered with short, soft hair.

r

A simple inflorescence in which the flowers are arranged

on short, nearly equal pedicels, at equal distances on an

elongated axis.

ruv

Bent backwards.r

An underground root-like stem that produces roots and

usually leaves at its apex.

r

Diamond-shaped.

ru

Strong and stoutly built.

s

The vital juice that circulates in s

Each of the divisions or leaves of

s

Saw-toothed.

su

Finely or minutely serrated or sa

s

Having no stalk, attached by thes

A tubular or enrolled part of the

the leaf of a grass.

G l o s s a r y

s

Growing singly or separately, not forming clusters or masses.

s

t

Three-leaved.

t


88/90

s

Approaching the shape of a sphere or ball.

sk

A small group of florets in grasses, forming part of the spike.

s

The male part of the flower.

s

Sucker of a plant. Stem running along the ground.

suu

Fleshy, full of juice.

t

A slender thread-like part of the plant, often spiral in form,

that stretches out and attaches to, or twines around, another

body to support the plant.

tuu

Tube-shaped or hollow.

twg

To grow in a twisted or spiral manner.

U

Umbrella-shaped inflorescence that springs from a common

centre.

r e f e r e n c e s


89/90


1. Space J (2005). Pacific Island Ecosystems at Risk (PIER)

Institute of Pacific Islands Forestry. PIER website version

5.0.20051212 (http://www.hear.org/Pier/index.html).

2. Noda K, Teerawatsakul M, Prakongvongs C andChaiwiratnukul L (1984). Major weeds of Thailand. ISBN

974-7619-78-4. Mass & Medias Co. Bangkok, Thailand.

142 pp.

3. Holm L, Doll J, Holm E, Pancho J and Herberger J (1996).

World Weeds. John Wiley & Sons Inc, New York, 1129 pp.

4. Cook BG, Pengelly BC, Brown SD, Donnelly JL, Eagles

DA, Franco MA, Hanson J, Mullen BF, Partridge IJ, Peters

M and Schultze-Kraft R (2005). Tropical Forages: an

Interactive Selection Tool. [CD-ROM], CSIRO, DPI&F(Qld),

CIAT and ILRI, Brisbane, Australia. (http://www.

tropicalforages.info).

5. Western Australian Herbarium (1998 ). FloraBase

The Western Australian Flora. Department of

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