Pest identification: Weeds

California PCA Exam Helper: Category E

Broadleaves | Grasses and sedges | Weed control

The list below includes all the weeds contained in the knowledge expectations for the Category E California PCA exams.

Remember, in addition to knowing these organisms, there are many other knowledge expectations for this exam. Get the complete list of knowledge expectations from DPR.

To pass the exam, you will be required to

  • identify the following plants and understand their basic biology and other information related to them that the knowledge expectations require
  • identify mature plants of all of the following species and seedling stages of those indicated with an asterisk (*).

The names below will link you directly to pages in the UC IPM weed photo gallery. Additional information is available for some species in the Pest Notes link.

Family Common name
(link to photo and description)
Scientific name Pest
Note link
Amaranthaceae Redroot pigweed*+ Amaranthus retroflexus
Asteraceae Yellow starthistle*# Centaurea solstitialis
link to yellow starthistle pest note

Hairy fleabane*+

Conyza bonariensis


Conyza canadensis
  Prickly lettuce* Lactuca serriola
  Common groundsel*#+ Senecio vulgaris
link to common groundsel pest note
  Annual sowthistle Sonchus oleraceus
Boraginaceae Coast fiddleneck*# Amsinckia menziesii var. intermedia
Brassicaceae Black mustard* Brassica nigra
  Shepherd's-purse* Capsella bursa-pastoris
  London rocket Sisymbrium irio
Caryophyllaceae Common chickweed* Stellaria media
link to chickweed pest note
Chenopodiaceae Common lambsquarters* Chenopodium album
  Russian thistle*+ Salsola tragus
link to Russian thistle pest note
Convolvulaceae Field bindweed*+ Convolvulus arvensis
link to field bindweed pest note
  Morningglories Ipomoea spp.
Euphorbiaceae Spotted spurge* Euphorbia maculata
link to spurge pest note
Fabaceae Black medic* Medicago lupulina
Geraniaceae Filaree*+ Erodium spp.
Lamiaceae Henbit* Lamium amplexicaule
Malvaceae Velvetleaf* Abutilon theophrasti
  Mallow* Malva spp.
link to mallow pest note
Oxalidaceae Bermuda buttercup Oxalis pes-caprae
link to oxalis pest note
Polygonaceae Common knotweed* Polygonum arenastrum
link to common knotweed pest note
  Smartweeds Polygonum spp.
Portulacaceae Purslane*+ Portulaca olearcea
link to purslane pest note
Solanaceae Jimsonweed# Datura stramonium
  Groundcherries Physalis spp.
  Nightshades*# Solanum spp.
Typhaceae Cattails+ Typha spp.
Urticaceae Nettles* Urtica spp.
link to nettles pest note
Zygophyllaceae Puncturevine*+ Tribulus terrestris
link to puncturevine pest note
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Grasses and Sedges
Poaceae Wild oat+ Avena fatua
  Large crabgrass* Digitaria sanguinalis
link to crabgrass pest note
  Junglerice Echinochloa colona
  Barnyardgrass* Echinochloa crus-galli
  Fescues Festuca spp.
  Foxtail barley+ Hordeum jubatum
  Hare barley+ Hordeum murinum spp. leporinum
  Sprangletops Leptochloa spp.
  Italian ryegrass Lolium multiflorum
  Witchgrass Panicum capillare
  Dallisgrass Paspalum dilatatum
link to dallisgrass pest note 
  Canarygrass Phalaris canariensis  
  Annual bluegrass* Poa annua
link to annual bluegrass pest note 
  Yellow foxtail Setaria pumila  
  Johnsongrass+ Sorghum halepense
Cyperaceae Smallflower umbrella sedge+ Cyperus difformis
  Yellow nutsedge+ Cyperus esculentus
link to nutsedge pest note
  Purple nutsedge Cyperus rotundus
link to nutsedge pest note

* You will be required to identify seedling stages, as well as the mature stage of these plants.

# Indicates weeds that are poisonous to animals.

+ Indicates weeds that have unique seed or vegetative growth structures.


Describe the use of the following methods for weed control

in alfalfa
in avocado
in peppers

Steaming in olives
in floriculture & nurseries
in peppers
Solarization in floriculture & nurseries
in strawberry
in walnut

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Statewide IPM Program, Agriculture and Natural Resources, University of California
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