CDFA Nematode Ratings

The California Food and Agricultural Code mandates that, the California Department of Food and Agriculture (CDFA) shall prevent the introduction and spread of injurious insect or animal pests, plant diseases, and noxious weeds. This statutory duty requires a pest policy which recognizes that organisms vary in their potential and actual harm to the agriculture and environment of California. Overall pest significance is based on the probability of spread of the pest, the potential economic damage, the presence of host species, the favorability of the climate and other factors. Pest ratings are based on that evaluation and provide the basis for determining what pest prevention activities are appropriate, at what level, and when and where those activities should be conducted.

(i) Pest ratings are intended as aids to inform County Agricultural Commissioners and other interested persons as to a particular pestâ€™s environmental, agricultural and biological significance, as well as its importance to the general public, and the action recommended by the California Department of Food and Agriculture (CDFA) to deal with the pest.

(ii) Each pest rating represents the view of CDFA of the statewide importance of the pest to the agricultural, horticultural, forestry, and public health interests of California. Local conditions may dictate more stringent action against the same pest in individual counties at the discretion of the County Agricultural Commissioner.

(iii) It is the policy of CDFA to use an Action-Oriented Rating System.� Pest ratings represent the policy of CDFA in relation to actions to be taken, consistent with existing statutes, which include authority for: the promulgation of quarantine, eradication, control, standards of cleanliness, and other regulations; holding and inspection; establishing host-free, weed-free, and special pest control districts; and for other regulatory activities.

A An organism of known economic importance subject to action enforced by the state (or County Agricultural Commissioner acting as a state agent) involving: eradication, quarantine regulation, containment, rejection, or other holding action.

Q An organism or disorder requiring a temporary A� action pending determination of a permanent rating. The organism is suspected to be of economic importance but its status is uncertain because of incomplete identification or inadequate information. In the case of an established infestation, at the discretion of the Director, CDFA may conduct surveys and may convene the Division Pest Study Team to determine a permanent rating.

B An organism of known economic importance that is of limited distribution in the State of California and is subject to: eradication, containment, control or other holding action at the discretion of the individual County Agricultural Commissioner. Or, an organism of known economic importance subject to state endorsed holding action and eradication only when found in a nursery.

C An organism already of common occurrence in the state that is subject to no state-enforced action outside of nurseries except to retard spread. At the discretion of the County Agricultural Commissioner. Or, an organism subject to no state enforced action except to provide for pest cleanliness in nurseries.

D No Action - plant parasites or other organisms of little or no economic importance, or organisms considered beneficial..

Newly detected pest species are subjected to a formal rating process that allows input from stakeholders and requires regular review of their status in the State. Greater detail on the pest rating system and the mitigating actions triggered by detection of a pest in each of the ratings is available at:

Pest Ratings are under frequent review and subjact to change as new information becomes available and new pests are detected. The most current list for nematodes is available at:

As of August 2026, nematode pest ratings for the State of California are listed below with links to greater information on the biology and management of the pest.

Genus/species	Common Name	Rating
Anguina funesta	Seed Gall Nematode	A
Anguina tritici	Wheat Seed-gall Nematode	A
Aphelenchoides besseyi	Strawberry Summer Dwarf Nematode Rice White-tip Nematode	A
*Asian Citrus Root-knot Nematodes* *Meloidogyne citri* *M. donghaiensis* *M. fujianensis* *M. indica* *M. jianyangensis* *M. kongi* *M. mingnanica*	Asian Citrus Root-knot Nematodes Complex	A
Belonolaimus longicaudatus	Sting Nematode	A
Bursaphelenchus cocophilus	Red Ring Nematode	A
Bursaphelenchus mucronatus	Pine Wood Nematode	A
Cactodera cacti	Cactus Cyst Nematode	A
Ditylenchus destructor	Potato Rot Nematode	A
Dolichodorus heterocephalus	Cobb's Awl Nematode; Awl Nematode	A
Globodera pallida	Pale or White Cyst Nematode	A
Globodera rostochiensis	Golden Nematode	A
Heterodera australis	Australian Cereal Cyst Nematode	A
Heterodera avenae	European Cereal Cyst Nematode	A
Heterodera ciceri	Chickpea Cyst Nematode	A
Heterodera filipjevi	Filipjev's Cereal Cyst Nematode	A
Heterodera glycines	Soybean Cyst Nematode	A
Heterodera latipons	Mediterranean Cereal Cyst Nematode	A
Heterodera sturhani	Sturhan Cereal Cyst Nematode	A
Heterodera ustinovi	Ustinov Grass Cyst Nematode	A
Hoplolaimus galeatus	Lance Nematode	A
Meloidogyne artiella	British Root-knot Nematode	A
Meloidogyne citri	Asian Citrus Root-knot Nematode	A
Meloidogyne donghaiensis	Asian Citrus Root-knot Nematode	A
Meloidogyne enterolobii	Root-knot Nematode	A
Meloidogyne fallax	False Columbia Root-knot Nematode	A
Meloidogyne floridensis	Peach Root-knot Nematode	A
Meloidogyne fujianensis	Asian Citrus Root-knot Nematode	A
Meloidogyne graminicola	Rice Root-knot Nematode	A
Meloidogyne hispanica	Sevillle Root-knot Nematode	A
Meloidogyne indica	Asian Citrus Root-knot Nematode	A
Meloidogyne jianyangensis	Asian Citrus Root-knot Nematode	A
Meloidogyne kongi	Asian Citrus Root-knot Nematode	A
Meloidogyne mali	Apple Root-knot Nematode	A
Meloidogyne mingnanica	Asian Citrus Root-knot Nematode	A
Meloidogyne minor	Yellow patch Root-knot Nematode	A
Meloidogyne partityla	Pecan Coffee Root-knot Nematode	A
Meloidoyne paranaensis	Parana Coffee Root-knot Nematode	A
Nacobbus aberrans	False Root-knot Nematode	A
Pratylenchus alleni	Allens Root Lesion Nematode	A
Pratylenchus loosi	Tea Root Lesion Nematode	A
Pratylenchus pratensis	Meadow Lesion Nematode	A
Radopholus similis	Burrowing Nematode	A
Rotylenchulus parvus	Reniform Nematode	A
Rotylenchulus reniformis	Reniform Nematode	A
Xiphinema basiri	Dagger Nematode	A
Xiphinema brasiliense	Dagger Nematode	A
Xiphinema bricolense	Dagger Nematode	A
Xiphinema diversicaudatum	European Dagger Nematode	A
Xiphinema setariae	Dagger Nematode	A
Anguina agrostis	Bent grass Seed-gall Nematode	B
Aphelenchoides oryzae	Rice White-tip Nematode	B
Helicotylenchus multicinctus	Spiral Nematode	B
Hemicycliophora arenaria	Sheath Nematode	B
Heterodera carotae	Carrot Cyst Nematode	B
Heterodera mani	Rye grass Cyst Nematode	B
Longidorus elongatus	Needle Nematode	B
Meloidogyne chitwoodi	Columbia Root-knot Nematode	B
Meloidogyne naasi	Barley Root-knot Nematode	B
Pratylenchus coffeae	Coffee Root Lesion Nematode	B
Pratylenchus hippeastri	Amaryllis Lesion Nematode	B
Xiphinema chambersi	Chamber's Dagger Nematode	B
Xiphinema index	California Dagger Nematode	B
Anguina pacificae	Pacific Shoot-gall Nematode	C
Aphelenchoides fragariae	Strawberry Foliar Nematode	C
Aphelenchoides ritzemabosi	Crysanthemum Foliar Nematode	C
Bitylenchus maximus	Stunt Nematode	C
Bursaphelenchus xylophilus	Pine Wood Nematode	C
Criconemoides spp. Mesocriconema spp.	Ring Nematodes	C
Ditylenchus dipsaci	Stem and Bulb Nematode	C
Helicotylenchus spp.	Spiral Nematodes	C
Hemicriconemoides chitwoodi	Sheathoid Nematode	C
Hemicriconemoides spp.	Sheathoid Nematode	C
Heterodera cruciferae	Cabbage Cyste Nematode	C
Heterodera fici	Fig Cyst Nematode	C
Heterodera schachtii	Sugarbeet Cyst Nematode	C
Heterodera trifolii	Clover Cyst Nematode	C
Hirschmanniella belli		C
Hirschmanniella diversa		C
Longidorus africanus	Needle Nematode	C
Longidorus orientalis	Needle Nematode	C
Melodogyne hapla	Northern Root-knot Nematode	C
Melodogyne haplanaria	Northern Root-knot Nematode	C
Meloidogyne graminis	Grass Root-knot Nematode	C
Meloidogyne incognita	Southern Root-knot Nematode	C
Meloidogyne incognita	Southern Root-knot Nematode	C
Meloidogyne javanica	Javanese Root-knot Nematode	C
Meloidogyne marylandi	Maryland Root-knot Nematode	C
Meloiodogyne arenaria	Peanut Root-knot Nematode	C
Merlinius spp.	Stunt Nematodes	C
Mesocriconema xenoplax	Ring Nematode	C
Paratrichodorus and Trichodorus spp.	Stubby Root Nematode	C
Paratrichodorus minor	Stubby Root Nematode	C
Paratrichodorus porosus	Stubby Root Nematode	C
Paratylenchus spp.	Pin Nematode	C
Pratylenchus brachyurus	Smooth-headed Lesion Nematode	C
Pratylenchus crenatus	Root Lesion Nematode	C
Pratylenchus neglectus	Root Lesion Nematode	C
Pratylenchus neglectus	Root Lesion Nematode	C
Pratylenchus penetrans	Root Lesion Nematode; Cobb's Lesion Nematode	C
Pratylenchus scribneri	Root Lesion Nematode; Scribner's Lesion Nematode	C
Pratylenchus thornei	Root Lesion Nematode	C
Pratylenchus vulnus	Walnut Root Lesion Nematode	C
Pratylenchus zeae	Root Lesion Nematode; Corn Lesion Nematode	C
Punctodera punctata	Grass Cyst Nematode	C
Quinisulcius spp.	Stunt Nematodes	C
Rotylenchus robustus	Spiral Nematode	C
Scutellonema spp.	Spiral Nematodes	C
Tylenchorhynchus spp.	Stunt Nematodes	C
Tylenchulus semipenetrans	Citrus Nematodes	C
Xiphinema americanum	American Dagger Nematode	C
Xiphinema bakeri	Baker's Dagger Nematode	C
Xiphinema californicum	Dagger Nematode	C
Xiphinema pachtaicum	Dagger Nematode	C
Xiphinema rivesi	Dagger Nematode	C

Genus/species	Common Name	Rating
Anguina funesta	Seed Gall Nematode	A
Anguina tritici	Wheat Seed-gall Nematode	A
Aphelenchoides besseyi	Strawberry Summer Dwarf Nematode Rice White-tip Nematode	A
*Asian Citrus Root-knot Nematodes* *Meloidogyne citri* *M. donghaiensis* *M. fujianensis* *M. indica* *M. jianyangensis* *M. kongi* *M. mingnanica*	Asian Citrus Root-knot Nematodes Complex	A
Belonolaimus longicaudatus	Sting Nematode	A
Bursaphelenchus cocophilus	Red Ring Nematode	A
Cactodera cacti	Cactus Cyst Nematode	A
Ditylenchus destructor	Potato Rot Nematode	A
Dolichodorus heterocephalus	Cobb's Awl Nematode; Awl Nematode	A
Globodera pallida	Pale or White Cyst Nematode	A
Globodera rostochiensis	Golden Nematode	A
Heterodera australis	Australian Cereal Cyst Nematode	A
Heterodera avenae	European Cereal Cyst Nematode	A
Heterodera ciceri	Chickpea Cyst Nematode	A
Heterodera filipjevi	Filipjev's Cereal Cyst Nematode	A
Heterodera glycines	Soybean Cyst Nematode	A
Heterodera sturhani	Sturhan Cereal Cyst Nematode	A
Heterodera ustinovi	Ustinov Grass Cyst Nematode	A
Hoplolaimus galeatus	Lance Nematode	A
Meloidogyne artiella	British Root-knot Nematode	A
Meloidogyne enterolobii	Root-knot Nematode	A
Meloidogyne floridensis	Root-knot Nematode	A
Meloidogyne hispanica	Sevillle Root-knot Nematode	A
Meloidogyne minor	Root-knot Nematode	A
Meloidoyne paranaensis	Parana Coffee Root-knot Nematode	A
Pratylenchus alleni	Allens Root Lesion Nematode	A
Radopholus similis	Burrowing Nematode	A
Rotylenchulus reniformis	Reniform Nematode	A
Xiphinema basiri	Dagger Nematode	A
Xiphinema diversicaudatum	European Dagger Nematode	A
Xiphinema setariae	Dagger Nematode	A
Anguina agrostis	Bent grass Seed-gall Nematode	B
Helicotylenchus multicinctus	Spiral Nematode	B
Hemicycliophora arenaria	Sheath Nematode	B
Heterodera carotae	Carrot Cyst Nematode	B
Heterodera mani	Rye grass Cyst Nematode	B
Longidorus elongatus	Needle Nematode	B
Meloidogyne chitwoodi	Columbia Root-knot Nematode	B
Meloidogyne naasi	Barley Root-knot Nematode	B
Pratylenchus coffeae	Root Lesion Nematode	B
Pratylenchus crenatus	Root Lesion Nematode	B
Pratylenchus hippeastri	Amaryllis Lesion Nematode	B
Xiphinema chambersi	Chamber's Dagger Nematode	B
Xiphinema index	California Dagger Nematode	B
Anguina pacificae	Pacific Shoot-gall Nematode	C
Aphelenchoides fragariae	Strawberry Foliar Nematode	C
Aphelenchoides ritzemabosi	Crysanthemum Foliar Nematode	C
Bursaphelenchus xylophilus	Pine Wood Nematode	C
Criconemoides spp. Mesocriconema spp.	Ring Nematodes	C
Ditylenchus dipsaci	Stem and Bulb Nematode	C
Helicotylenchus spp.	Spiral Nematodes	C
Hemicriconemoides chitwoodi	Sheathoid Nematode	C
Hemicriconemoides spp.	Sheathoid Nematode	C
Heterodera cruciferae	Cabbage Cyste Nematode	C
Heterodera fici	Fig Cyst Nematode	C
Heterodera schachtii	Sugarbeet Cyst Nematode	C
Hirschmanniella belli		C
Hirschmanniella diversa		C
Longidorus africanus	Needle Nematode	C
Longidorus orientalis	Needle Nematode	C
Melodogyne hapla	Northern Root-knot Nematode	C
Meloidogyne incognita	Southern Root-knot Nematode	C
Meloidogyne marylandi	Root-knot Nematode	C
Meloiodogyne arenaria	Peanut Root-knot Nematode	C
Merlinius spp.	Stunt Nematodes	C
Mesocriconema xenoplax	Ring Nematode	C
Paratrichodorus minor	Stubby Root Nematode	C
Paratrichodorus porosus	Stubby Root Nematode	C
Paratrichodorus spp.	Stubby Root Nematode	C
Paratylenchus spp.	Pin Nematode	C
Pratylenchus brachyurus	Smooth-headed Lesion Nematode	C
Pratylenchus neglectus	Root Lesion Nematode	C
Pratylenchus penetrans	Root Lesion Nematode; Cobb's Lesion Nematode	C
Pratylenchus scribneri	Root Lesion Nematode; Scribner's Lesion Nematode	C
Pratylenchus thornei	Root Lesion Nematode	C
Pratylenchus zeae	Root Lesion Nematode; Corn Lesion Nematode	C
Punctodera punctata	Grass Cyst Nematode	C
Quinisulcius spp.	Stunt Nematodes	C
Scutellonema spp.	Spiral Nematode	C
Tylenchorhynchus spp.	Stunt Nematodes	C
Tylenchulus semipenetrans	Citrus Nematodes	C
Xiphinema americanum	American Dagger Nematode	C
Xiphinema bakeri	Baker's Dagger Nematode	C

Pest Rating System: General Principles
Action Oriented Pest Rating System
Pest Ratings for Nematodes in California (with links to Nemaplex pest information pages
Nematodes in alphabetical order of Genus and species
Nematodes in order of pest ratings	Return to Management Menu
Previoous version of the pest rating list (prior to 2024)	Go to Nemaplex Main Menu
Previoous version of the pest rating list (prior to 2021)

Genus/species	Common Name	Rating
Aphelenchoides besseyi	strawberry summer dwarf nematode	A
Belonolaimus spp.	sting nematode	A
Belonolaimus longicaudatus	sting nematode	A
Dolichodorus heterocephalus	Cobb's awl nematode	A
Globodera pallida	white cyst potato nematode	A
Globodera rostochiensis	golden nematode	A
Hemicycliophora arenaria	sheath nematode	A
Heterodera avenae	oat cyst nematode	A
Heterodera glycines	soybean cyst nematode	A
Hirschmanniella oryzae	rice root nematode	A
Nacobbus aberrans	sugarbeet false root-knot nematode	A
Radopholus similis	burrowing nematode	A
Rotylenchulus reniformis	reniform nematode	A
Xiphinema diversicaudatum	European dagger nematode	A

Ditylenchus destructor	potato rot nematode	B
Meloidogyne chitwoodi	Columbia root-knot nematode	B
Meloidogyne naasi	barley root-knot nematode	B
Xiphinema index	California dagger nematode	B

Anguina agrostis	bent grass nematode	C
Anguina tritici	wheat nematode	C
Aphelenchoides fragariae	strawberry spring dwarf nematode	C
Aphelenchoides ritzemabosi	chrysanthemum foliar nematode	C
Bursaphelenchus xylophilus	pine wood nematode	C
Ditylenchus dipsaci	stem and bulb nematode	C
Heterodera cruciferae	cabbage cyst nematode	C
Heterodera schachtii	sugarbeet cyst nematode	C
Longidorus africanus	no common name known	C
Meloidogyne graminis	root-knot nematode	C
Meloidogyne spp.	root-knot nematode	C
Paralongidorus microlaimus	needle nematode	C
Pratylenchus brachyurus	smooth-headed lesion nematode	C
Pratylenchus coffeae	coffee lesion nematode	C
Pratylenchus penetrans	Cobb's lesion nematode	C
Pratylenchus vulnus	walnut lesion nematode	C
Pratylenchus zeae	corn lesion nematode	C
Rotylenchulus parvus	no common name known	C
Tylenchulus semipenetrans	citrus nematode	C
Xiphinema americanum	American dagger nematode	C
Xiphinema bakeri	dagger nematode	C
Xiphinema brevicolle	dagger nematode	C
Xiphinema coxi	dagger nematode	C
Xiphinema insigne	dagger nematode	C
Xiphinema vuittenezi	dagger nematode	C

Anguina amsinckiae	seed gall nematode	D
Anguina balsamophila	seed gall nematode	D
Aphelenchoides composticola	a fungus-feeding nematode	D
Atalodera lonicerae	no common name known	D
Atalodera ucri	no common name known	D
Bakernema variabile	spine nematode	D
Cacopaurus spp.	sessile nematode	D
Cactodera cacti	cactus cyst nematode	D
Criconema sp.	spine nematode	D
Criconemella axeste	ring nematode	D
Criconemella curvata	ring nematode	D
Criconemella macrodora	ring nematode	D
Criconemella parva	ring nematode	D
Mesocriconema xenoplax	ring nematode	D
Criconemoides spp.	ring nematode	D
Crossonema fimbriatum	spine nematode	D
Ditylenchus intermedius	a bulb and stem nematode	D
Dolichodorus spp.	awl nematode	D
Gracilacus spp.	pin nematode	D
Helicotylenchus spp.	spiral nematode	D
Helicotylenchus spicaudatus	spiral nematode	D
Hemicriconemoides spp.	sheathoid nematode	D
Hemicycliophora megalodiscus	sheath nematode	D
Hemicycliophora spp.	sheath nematode	D
Heterodera fici	fig cyst nematode	D
Heterodera trifolii	clover cyst nematode	D
Hirschmanniella belli	rice root nematode	D
Hirschmanniella caudacrena	rice root nematode	D
Hirschmanniella gracilis	rice root nematode	D
Hoplolaimus spp.	lance nematode	D
Longidorus spp.	needle nematode	D
Merlinius brevidens	stunt nematode	D
Merlinius conicus	stunt nematode	D
Merlinius grandis	stunt nematode	D
Merlinius superbus	stunt nematode	D
Nacobbus dorsalis	false root-knot nematode	D
Pararotylenchus sp.	spiral nematode	D
Paratrichodorus allius	stubby- root nematode	D
Paratrichodorus minor	Christie's stubby- root nematode	D
Paratrichodorus porosus	stubby- root nematode	D
Paratrichodorus renifer	stubby- root nematode	D
Paratylenchus spp.	pin nematode	D
Pratylenchus convallariae	lesion nematode	D
Pratylenchus crenatus	lesion nematode	D
Pratylenchus goodeyi	lesion nematode	D
Pratylenchus hexincisus	lesion nematode	D
Pratylenchus minyus	lesion nematode	D
Pratylenchus neglectus	lesion nematode	D
Pratylenchus pratensis	lesion nematode	D
Pratylenchus scribneri	lesion nematode	D
Pratylenchus thornei	lesion nematode	D
Quinisulcius acutus	stunt nematode	D
Quinisulcius capitatus	stunt nematode	D
Rotylenchus spp.	spiral nematode	D
Sarisodera hydrophylla	no common name known	D
Scutellonema spp.	spiral nematode	D
Trichodorus spp.	stubby-root nematode	D
Tylenchorhynchus spp.	stunt nematode	D

Bursaphelenchus mucronatus	pine wood nematode	Q
Pratylenchus flakkensis	lesion nematode	Q
Xiphinema brasiliense	dagger nematode	Q
Xiphinema setariae	dagger nematode	Q
Xiphinema vulgare	dagger nematode	Q

California Department of Food and Agriculture - Pest Rating System

Rev 08/31/26

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