psyllids mgmt

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Integrated Pest Management for Home Gardeners and Landscape Professionals

P SYLLIDS

Statewide Integrated Pest Management Program April 2014

PEST NOTES Publication 7423

Psyllids (Hemiptera: Psylloidea) are

small insects that suck plant juices. Theadults resemble miniature cicadas andare sometimes called jumping plantlice.Over 160 psyllid species occur on na-tive or introduced landscape plants inCalifornia. Several psyllid species arepests of crops such as citrus, olive, pear,potato, and tomato. Each kind of psyl-lid feeds on only one plant species orclosely related group of plants. Mostpsyllids native to California are rela-tively uncommon and rarely becomepests. Generally psyllids that have become pests are exotic species inad-

vertently introduced from other coun-tries. Exotic species make up about 11%of the psyllid species in California.

IDENTIFICATIONAND LIFE CYCLE

Adult females lay eggs that hatch anddevelop through about ve instars(nymphal growth stages) before matur-ing into winged adults. Psyllids becomeabundant in spring when temperatureswarm and host plants produce newgrowth ushes. Most psyllid speciesrequire only a few weeks during warm

weather to complete development fromegg to adult. Development and repro-duction stop or greatly slow duringcool weather, and in some species hotweather can suppress their populations.Most species have about 3 to 5 genera-tions a year, but some species may onlyhave one generation a year.

Adults hold their wings rooike overtheir bodies and are 1/12 to 1/5 inchlong, similar in size to large wingedaphids. They have strong jumping legsand short antennae. Nymphs are at-

tened and less active than adults. Don’tconfuse psyllid adults with similarlooking but harmless psocids (Figure1). Psocids feed on fungi, includingsooty mold growing on psyllid honey-

dew. Mature psyllids commonly jump

when disturbed, while psocids runor y away. Psocids have a more nar-row “neck” or separation between thehead and the thorax and have chewingmouthparts, whereas psyllids havetubular, sucking mouthparts.

Nymphs of many psyllid species se-crete wax laments or form covers,often called ``lerps,” composed of waxand solidied honeydew. These cov-ers can aid in identication of psyllidspecies in the eld. Because several

hundred species of psyllids occur juston acacia and eucalyptus trees in Aus-tralia, exotic, new psyllid species arelikely to be introduced into Californiawhere these Australian plants have been introduced for landscaping. Takeunfamiliar psyllids to your countyagricultural commissioner or local Uni-versity of California (UC) CooperativeExtension oce for identication.

Native Psyllids

Over 140 species of psyllids are con-

sidered native to California. They donot appear to harm their hosts anddo not warrant control in gardens orlandscapes. Certain species can betemporarily abundant; but their popu-lations soon decline naturally, as manyare heavily attacked by their naturalenemies, including parasitic wasps.Common native psyllids include: • manzanita psyllid, Neophyllura

(=Euphyllura) arctostaphyli onArctostaphylos species

• sumac psyllids, Calophya species on

Rhus species, such as lemonade berry and sugarbush • willow psyllids, including Psylla

alba and P. americana , on variousSalix species

Introduced Psyllids

About 18 psyllid species introducedaccidentally from other countries can

be pests in gardens and landscapes,including psyllids recently introducedon citrus, olive, pittosporum, androsewood tree or tipu (see Table 1and Figure 13). Earlier invasive spe-cies include psyllids infesting acacia,eugenia, eucalyptus, Grecian laurel

or sweet bay, pear, pepper tree, andpotato. Certain species are now undergood biological control, and biologicalcontrol programs are being developedfor new pests like the Asian citruspsyllid. Psyllids are benecial in somesituations. The melaleuca psyllid,Boreioglycaspis melaleucae , for example,has been deliberately introduced fromAustralia into Florida to help controlpaperbark tree, Melaleuca quiquenervia ,which is a serious invasive weed tree.

DAMAGE

Psyllids suck plant juices and excretesticky honeydew on which blackishsooty mold grows. Some species se-crete pale or white wax masses, pelletsor strands, or coverings called lerps

Figure 1. Adult psocid (top) and anadult psyllid.



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(Figures 2 and 3). High psyllid popu-lations reduce plant growth or causeterminals to distort, discolor, becomegalled, or die back. Certain species,such as the olive and tipu psyllids, cancause premature leaf drop. The eugenia

and peppertree psyllids cause leavesto develop a pit around the spot whereeach nymph settles and feeds (Figures4 and 5). Excessive honeydew excretionand wax secretions can also damageplants or property below the infestedfoliage.

Pear psyllid, Psylla pyricola , injects aplant toxin that blackens and “burns”pear foliage and fruit skins. The potato,or tomato psyllid, Bactericera cockerelli ,occasionally causes infested potatoto develop yellow, severely distorted,

dwarfed leaves and shoots. The adultvectors (introduces during its feeding)the bacterial pathogen causing “zebrachip” disease, which causes fried pota-toes to develop prominent black stripes.The Asian citrus psyllid, Diaphorinacitri , damages citrus directly by feed-ing on new leaf growth (ush) and isa vector of the bacterium CandidatusLiberibacter asiaticus that can result inthe lethal and incurable citrus diseasehuanglongbing.

MANAGEMENT

Most psyllids on landscape trees andshrubs do not need to be managedto protect plant health. Species war-ranting control action include Asiancitrus psyllid (Figure 6) and, in certainsituations, other invasive psyllid spe-cies that cause intolerable damage (seeTable 1). When taking control actionsuse an integrated program incorporat-ing appropriate plant care and certaininsecticides, preferably less-persistentproducts that provide adequate controland help conserve natural enemies.

Exclude Foreign Pests. Many of ourworst pests were introduced from otherstates or countries. To prevent newpest introductions during planting andtravel: • Do not bring fruit, plants, seeds,wood products, or soil into Californiaunless you know they were certied as

being pest-free or inspected by agricul-tural ocials. This includes some on-

line purchases that may not go throughthe required inspection process. • Clean up, dispose of, or removediseased or infested plant material inways that assure pests are not movedto new locations. Many introduced

pests that are in California have notyet spread throughout the entire state.These can be kept localized unlesspeople inadvertently spread them. • Buy only pest-free plants from repu-table, local nurseries.

Take any unfamiliar pests to the localcounty agricultural commissioner orUC Cooperative Extension oce foridentication or telephone the Cali-fornia Department of Food and Agri-culture (CDFA) Exotic Pest Hotline at1-800-491-1899. Be sure you put pests in

a sealed bag or bottle before transport-ing them.

Monitoring

Most psyllid damage is aesthetic. Toler-ance for aesthetic damage varies withpeople’s attitude and knowledge andthe situation, such as the location andspecies of plants and psyllids. Exceptfor adults, such as the Asian citruspsyllid, that vector plant pathogensmost psyllid damage is caused byfeeding nymphs. Determine the levelof damage you are willing to tolerateand monitor psyllid abundance onsusceptible plants on a regular basis.Initiate control actions before psyllidabundance or damage approach thelevel that you previously found to beintolerable.

To help you decide whether and whento take control action, monitor psyl-lids by using sticky traps to captureadults, beat or shake foliage to dislodgeadults so they can be counted, andinspect susceptible plant parts for eggs,nymphs, and adults. Regular moni-toring helps you determine whethernatural enemies are becoming moreabundant and may provide the neededlevels of biological control or the mosteective time to take action, if manage-ment with pesticides is warranted.

In addition to monitoring psyllids, ob-serve the seasonal growth of plants. Pe-riodically examine plants for the pres-

ence and relative abundance of newgrowing tips, which typically are softer,somewhat dierently colored, andundersized in comparison with oldertissue. You may discover an annualcycle to psyllid abundance; populationincreases typically coincide with newplant growth. Conversely, the presence

Figure 2. Olive psyllids feed beneathwhite wax they secrete.

Figure 3. Waxy covers of the

spottedgum lerp psyllid.

Figure 4. Pits form where eugeniapsyllid nymphs feed on the underside

of leaves.



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of large numbers of psyllid adults maynot be a cause for concern when thereis no longer any new ush of growthfor egg laying, as the season is ending.The same number of adults observedwhen a plant is weak or growing poor-

ly might warrant closer attention.

Traps. Hang yellow, sticky-coatedtraps in host plants as an ecient wayto monitor the presence and relativeabundance of adult psyllids and cer-tain psyllid parasites and predators.Adults of many types of insects are at-tracted to the yellow color and becomestuck to the trap. A signicant increasein the number of psyllids in traps canindicate it is time to make a foliar sprayof contact insecticide or to shear pruneplant terminals (such as with eugenia)

to remove psyllid-infested tips whilestill conserving parasites as discussed

below.

Inspect traps once each week and count(or estimate) and record the numberof adult psyllids and their naturalenemies. If insects are abundant, youcan estimate their numbers by usingve range categories: no psyllids, 1 to10, 11 to 25, 26 to 100, or more than 100psyllids per trap. Count and record thepsyllids separately from the naturalenemies. Following each count, scrape

o all the insects and debris or replacetraps if they are too fouled. Periodiccleaning or replacing of traps is essen-tial to keep the surface sticky and makeit easier to identify and count newlytrapped insects.

Beat or shake sampling. Adult psyllids,certain natural enemies, and other eas-ily dislodged insects can be detectedand counted by shaking or tappinginfested terminals to knock insectsonto a collecting surface underneathfoliage (Figure 7).

Hold a light-colored plastic tray,framed cloth, or clipboard with a whitesheet of paper beneath foliage or placea small cloth on the ground beneathlow-hanging branches. To dislodge in-sects onto the collecting surface, shakeor beat the branch a xed number oftimes, such as once or twice. A typicalprogram may sample from four loca-

tions per plant, one branch from eachcardinal direction. Do this once eachweek during the time of year whenpsyllids can be a problem, generallyspring to midsummer for most spe-cies. Monitor about the same time ofday, preferably early morning whentemperatures are cooler, which makesadults less active and easier to count.In most situations you can ignore anydislodged immature psyllids. Adultsare the egg-laying stage and the sea-sonal cycle of the adult populations,highs and lows, indicates when thedamaging nymphal stages are likely to

become more or less abundant.

Cultural Control

To suppress populations of phloem-

sucking insects, such as psyllids, pro-vide appropriate irrigation and do notapply nitrogen fertilizer to establishedwoody plants, unless foliage appear-ance or plant growth is unsatisfactory

because of a conrmed nutrient de-ciency. Be aware that foliar symptomsof nutrient deciency are often caused

by poor root health and impropersoil conditions, such as waterloggedsoil from inadequate drainage andfrequent irrigation, alkaline (highpH) soil, and root infection by fungal

pathogens. Adding fertilizer will notremedy these problems.

For plants adapted to summer rainfall,consider irrigating them during sum-mer and fall. For eucalyptus, droughtstress increases damage from both lerppsyllids and longhorned borers. For es-tablished plants, apply water beneaththe outer canopy, not near trunks.Avoid frequent, shallow watering thatis often used for lawns. A generalrecommendation is to irrigate estab-lished trees infrequently (possibly

once a month during drought periods) but with sucient amounts so that thewater penetrates deeply into soil (per-haps about 1 foot or more below thesurface). Waterlogging (soggy soil), es-pecially near the trunk, favors root andcrown diseases. The specic amountand frequency of water needed variesgreatly depending on the site condi-tions and plant species.

Minimize shearing or clipping ofterminals. Shearing stimulates new

growth, which is preferred by psyl-lids for feeding and egg laying. Prune by cutting plants just above branchcrotches and nodes instead of shear-ing o terminals. An exception iseugenia and other shrubs that aresheared several times each year toprovide a smooth, dense canopy sur-face for ornamental purposes, such asformal hedging or topiary pruning.

Figure 5. Peppertree psyllid adult (left)

and a nymph secreting wax.

Figure 6. Adult Asian citrus psyllid

(left) and wax secreted by nymphs.

Figure 7. Shaking low branches over acloth to observe dislodged insects.



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and Albizia species that are not pre-ferred by acacia psyllid.

Asian Citrus Psyllid. Buy citrus andother Rutaceae family plants onlyfrom reputable local nurseries to avoid

introducing into new areas this psyl-lid or the citrus-killing pathogen thatcauses huanglongbing (HLB) disease,also called citrus greening disease. Inlocations not known to be infested withAsian citrus psyllid, inspect your citrustrees once a month whenever tiny newleaves (feather ush growth) are pres-ent during warm weather, especiallyin the spring and fall. Slowly walkaround each tree and examine newush growth. Look for twisted leaves,waxy deposits, honeydew, sooty mold,and adult psyllids. Distinguish psyl-lids from aphids, scales, whiteies, andcertain other insects that can also causehoneydew and sooty mold.

If you think citrus psyllids are present,use a hand lens to examine succulentleaf tips for tiny yellow eggs, psyllidnymphs with waxy tubules, and psyllidadults. If you think you have found thispsyllid in uninfested locations, imme-diately contact the CDFA Exotic PestHotline at 1-800-491-1899.

In certain areas the CDFA may applyinsecticides to residential host plants tocontrol this psyllid. In known infesta-tion areas, consider applying insecti-cide yourself or hiring a pest controlcompany to control this psyllid andhelp protect citrus from the psyllid-vectored huanglongbing disease. Incitrus, if applying systemic insecticideto soil as discussed below, make theapplication during summer or earlyfall when roots are active and plantsare not blooming or about to bloom. Aparasitic wasp, Tamarixia radiata , from

Pakistan has been released and estab-lished in California and is spreading.This natural enemy can help to controlAsian citrus psyllid, if Argentine antsand other invasive ants are selectivelycontrolled as discussed in Pest Notes:Ants. These pest ants harvest honeydewfrom Asian citrus psyllid nymphs andprotect them from natural enemies. SeePest Notes: Asian Citrus Psyllid f or moreinformation.

Well-timed shearing can suppresseugenia psyllid populations.

Avoid planting problem-prone plantsand consider replacing them with pest-resistant species and cultivars that arewell adapted to local conditions. Seethe examples below for the acacia, eu-calyptus, and peppertree psyllids.

Biological Control

Parasites and predators biologicallycontrol many native and certain intro-duced psyllid species. Important natu-ral enemies of psyllids include lady

beetles, lacewing larvae, predaceous bugs, and tiny parasitic wasps (Figures8, 9, and 10). Psyllids under moderateto good biological control include the

bluegum psyllid and, especially incoastal regions, the redgum lerp psyl-lid. The acacia, eugenia, and peppertreepsyllids are under good biocontrol inwarmer locations but are sporadicallyabundant in coastal regions (Table 1).Introduced parasites have also reducedthe abundance of lemongum psyllidand spottedgum lerp psyllid and insome coastal locations this biologi-cal control may keep these pests from

becoming an intolerable problem. Inmost situations these species warrantno management except to conserve

natural enemies.

Species-Specifc Management Methods

Acacia Psyllid. A purplish predatory bug and a small black lady beetle (Fig-ure 11) generally provide good biologi-cal control of acacia psyllid (Figures9 and 11, Table 1). However in SanFrancisco Bay coastal locations, thesepredators may not become eectiveuntil June or July. Tolerate psyllids forseveral weeks when they are temporar-

ily abundant, typically during Apriland May, and conserve natural en-emies until predators provide control.Alternatively, temporarily reduce highpopulations by thoroughly coveringnew outer and upper canopy acaciagrowth with a nonresidual or short-residual insecticide as discussed be-low. To entirely eliminate the problem,replace susceptible plants. See Pests ofLandscape Trees and Shrubs for Acacia

Figure 8. Adult multicolored Asianlady beetle eating a redgum lerppsyllid nymph.

Figure 9. Adult minute pirate bug, Anthocor is nemoralis, feeding on apsyllid nymph.

Figure 10. Bluegum psyllids with theemergence hole of a parasitic wasp,Psyllaephagus pilosus.

Figure 11. Adult lady beetle, Diomus pumilio, eating acacia psyllid eggs.

http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7411.html











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Eucalyptus (Gum Tree) Psyllids. Inregions with summer drought con-sider providing eucalyptus trees withsupplemental water during summerand fall as described above in CulturalControl. Drought-stressed eucalyptus

are more susceptible to psyllids andPhoracantha species longhorned bor-ers. Apply water beneath the outercanopy infrequently but with sucientamounts so that the water penetratesdeeply into the soil. For example, aboutonce per month water trees slowlythrough drip emitters that run continu-ously for several days.

Avoid fertilizing eucalyptus becausethis increases tree susceptibility topsyllids. Use slow-release nutrientformulations if other plants near euca-

lyptus trees require fertilization. Whenplanting trees choose species that arewell adapted to local conditions, in-cluding tolerance for the prevailingmoisture conditions. Consult Pest Notes:Eucalyptus Redgum Lerp Psyllid for moreinformation on Eucalyptus species’relative susceptibility to leaf-chewing

beetles, longhorned borers, and psyl-lids; and consider planting species thatare not susceptible to these pests.

Eugenia Psyllid. In cooler areas nearthe California coast, eugenia psyllid

parasite populations may not increasequickly enough to provide satisfac-tory control during the spring. Wherepruning or other control methods areplanned, inspect plants regularly fornew growth beginning in late winter.Also consider regular monitoring foradult psyllids, especially when manag-ing many eugenia plants.

Regular shearing of terminals reduceseugenia psyllid abundance and is theonly way to eliminate damaged foli-age, aside from waiting for old leaves to

drop (Figure 12). No pesticide or othertreatment will restore pitted foliage toa healthy appearance. Prune terminalsafter maximum spring growth ap-pears or about 3 weeks after the rstpeak in adult psyllid density, as deter-mined using methods described abovein Monitoring. Consider shearingeugenia tips at about 3-week intervalsthroughout the period of new plantgrowth or as long as adult psyllids are

abundant. Leave eugenia clippings asmulch near the shrubs for at least 3weeks to allow parasites within psyllidnymphs to complete their developmentand emerge. Eugenia psyllid eggs andnymphs on the cut foliage will die.

Olive Psyllid. Avoid frequent irriga-tion near olive tree trunks and providegood soil drainage to improve treehealth and resistance to pests. Pruneo or thin interior limbs in hot loca-tions to increase psyllid exposure toheat and increase air circulation, whichsuppresses its populations. Naturalenemies are being investigated forpotential introduction. Where psyllidpopulations were intolerable the previ-ous year and insecticide use is planned,target the rst generation, typically

present March to April. Olive psyllidsare more dicult to control duringtheir second generation (May to June),when most of their waxy excrementand damage occurs.

Peppertree Psyllid. Peppertree psyl-lids are often satisfactorily controlled by an introduced parasitic wasp,Tamarixia schina. No additional controlis required in many situations. Pep-pertree psyllid produces relatively littlehoneydew and its distortion of foliagecan be easily overlooked on the nely

divided leaves of pepper trees, espe-cially on branches above eye level.

To improve pepper tree health andits ability to tolerate psyllids, provideadequate soil drainage and removeirrigated landscape near trunks. Thesepractices are more important methodsof improving pepper tree health thanapplying pesticides. Pepper trees areadapted to well drained, sandy soiland summer drought. Planting trees inheavy clay soils and in lawns and othersummer-watered landscapes promotes

root diseases and causes trees to de-cline and die.

In cooler locations, where biologi-cal control is less eective, considergrowing alternative species if psyllidscannot be tolerated. Australian wil-low myrtle or peppermint tree, Agonis fexuosa; desert willow, Pittosporum phillyraeoides; and Australian willow,Geijera parvifora , are relatively drought-

tolerant and have a weeping appear-ance that resembles the pepper tree; butthey are not aected by the peppertreepsyllid. Avoid planting Peruvian pep-per, Schinus terebinthifolius; it is invasivein natural areas of California whereit forms dense thickets and displacesnative plants.

Chemical Control

Where psyllids or their damage areintolerable and insecticides will beapplied, the most appropriate prod-uct will depend on the situation. The

recommended products may includenonresidual, contact insecticides; short-residual, translaminar insecticides;and long-lasting, systemic insecticides.Apply insecticide only to psyllid hostplants and in situations where psyllidsand their damage cannot be tolerated.Completely read and follow the prod-uct label instructions for the safe andeective use of the insecticide.

Insecticides Most Compatible withIntegrated Pest Management (IPM).Nonresidual contact insecticides and

certain short-residual products havethe least adverse eect on bee andnatural enemy populations. If psyllidswere intolerable the previous year, the best time to spray these products iswhen young psyllid nymphs are pres-ent and before psyllids have becometoo abundant or produced excessivewaxiness or other damage. Thoroughlyspray infested parts, such as succulentterminals and the underside of leaves.

Figure 12. Leave clippings fromeugenia bushes as mulch on the groundfor at least 3 weeks to allow parasites tocomplete their development and returnto the shrubs where they lay eggs thatparasitize other psyllid nymphs.








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More than one application per seasonis generally needed during the timeswhen psyllids are most active.

Nonresidual, Contact Insecticides. Theseproducts can control psyllids whereinfested plant parts can be thoroughly

sprayed. Nonresidual, contact insec-ticides have low toxicity to people,pets, and pollinators. They have littleadverse impact on biological pest con-trol, because they do not leave toxicresidues that would kill natural en-emies migrating in after their applica-tion. Nonresidual contact insecticidesinclude azadirachtin (AzaMax, SaferBrand BioNeem), neem oil (Green LightNeem, Schultz Garden Safe Brand

Neem), insecticidal soap (Safer), andnarrow-range oil (Bonide HorticulturalOil, Monterey Horticultural Oil).

Unless plants are too tall to achieveadequate coverage and avoid excessivedrift of spray, these products are an

especially good choice on acacia, euge-nia, pepper tree, and other hosts withnatural enemies that may not provide

biological control until later in theseason or are only partially eective atthat location. Spraying nonpersistentinsecticides early in the season beforenatural enemies build up and migratefrom nearby unsprayed plants is com-patible with late-season biologicalcontrol. Monitor after the application.

If natural enemies become abundant,avoid spraying again.

Spinosad. Spinosad is a fermentationproduct of a naturally occurring bacte-rium. This insecticide (Captain Jack’sDeadbug Brew, Conserve, Monterey

Garden Insect Spray) persists about 1week. It has translaminar activity (isabsorbed short distances into planttissue) so it can better reach psyllidnymphs in leaf and shoot crevices andpits in comparison with the productsabove. Spinosad can be toxic to certainnatural enemies (e.g., predatory mites,syrphid y larvae) and bees whensprayed and for about 1 day afterward;

Table 1. Introduced Psyllid Pests in California Landscapes.

Common Name,

Scientifc Name

Host Plants,

Scientifc Name

Damage1 Biological Control Status:

Principal Natural Enemies2

acacia psyllid, Acizzia uncatoides

Acacia spp. distorted terminals, abundantinsects in spring

predators effective by June or July, but psyllid sporadically abun-dant during spring: purplish minute pirate bug, Anthocor is nemora-lis; small blackish lady beetle, Diomus pumilio

Asian citrus psyllid,Diaphorina citri

citrus and other closely-related Rutaceae familyplants, e.g., orange jas-mine, Murraya paniculata

distorted terminals, abundantwax, vectors plant-killingCandidatus Liberibacter sp.bacterium that causes Huan-glongbing, citrus greeningdisease

biological control not currently relied on in California and notexpected to prevent pathogen vectoring problem

bluegum psyllid,Ctenarytaina eucalypti

baby blue gum,Eucalyptus pulverulent a; juvenile foliage of bluegum, E. globulus

occulent wax on leaves andterminals, adults mating tail-to-tail appear mothlike

biologically controlled, except sporadically in commercial foliageproduction when natural enemies are disrupted: Psyllaephagus

pilosus

eugenia psyllid,Trioza eugeniae

eugenia, Syzygium paniculatum

distorted terminals, pittedfoliage, adults are mostlydark brown with a white bandaround the abdomen

partially controlled, can be a problem during spring in cooler areasnear the coast unless terminals are repeatedly sheared and leftas mulch beneath eugenia for parasite emergence: Tamarixiadahlsteni

laurel psyllid,Trioza alacris

Grecian laurel, Laurusnobilis

distorted terminals, galledleaves, stunted plant growth

not documented

lemongum psyllid,Cryptoneossa triangula

lemon gum, Eucalyptuscitriodora; spotted gum,E. maculata

free-living and under lerps ofspottedgum lerp psyllid

partially controlled, especially in coastal locations: Psyllaephagus perplexans

olive psyllid,Euphyllura olivina

mock privet, Phillyrealatifolia; olive, Oleaeuropaea; Russian olive,Elaeagnus angustifolia

occulent white wax on leavesand twigs, reduced oliveproduction, slow tree growth,premature leaf drop

psyllid recently introduced, not currently controlled biologically

peppertree psyllid,Calophya schini

pepper tree, Schinusmolle

distorted terminals, pittedleaves

biologically controlled in warmer parts of the state, parasite lesseffective in cooler areas: Tamarixia schina

pittosporum psyllid,Cacopsylla tobirae

mock orange,Pittosporum spp.

swollen twigs, pitted leaves,shoot dieback, wax strands


redgum lerp psyllid,Glycaspis brimblecombei

river red gum, Euca-lyptus camaldulensis;ooded gum, E. rudis;and forest red gum,E. tereticornis

pale, hemispherical caps onleaves, premature defoliation

biologically controlled in at least coastal regions, but may still be aproblem in some interior regions: Psyllaephagus bliteus

spottedgum lerp psyllid,Eucalyptolyma maideni

lemon gum, Eucalyptuscitriodora and spot-ted gum, Eucalyptus

maculata

funnel-shaped coveringswith openings that resembleskeletal ribs

partially controlled, especially in coastal locations: Psyllaephagus parvus

tipu psyllid,Platycorypha nigrivirga

rosewood tree, Tipuanatipu

distorted shoots, prematureleaf drop, waxy pellets


1 All psyllids produce sticky honeydew on which dark sooty mold grows.2.The natural enemies named are tiny species of parasitic wasps (Hymenoptera), except for those of acacia psyllid.



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do not apply spinosad to plants that areowering.

Insecticides More Toxic to Psyllidsand Benefcial Insects. Systemicneonicotinoids are the most practi-

cal insecticides for psyllids infestinglarge plants and where the more IPM-compatible products are inadequate.Neonicotinoids such as dinotefuran(Safari) and imidacloprid (Bayer Ad-vanced Tree & Shrub Insect Control,Merit) are absorbed by one plant part(e.g., roots or trunks) and moved (trans-located) to other plant parts. Someproducts can be sprayed onto plantfoliage, but drenching or injecting soil,or for woody species injecting or spray-ing trunks (if the product is labeled forthese application methods), minimizes

environmental contamination andmay be more eective than sprayingfoliage. Trunk application of systemicinsecticide can provide relatively rapidcontrol. With soil application, there is alonger time delay between applicationand insecticide action.

Neonicotinoids have low, moderate, orsevere adverse impact on natural en-emies and pollinators, varying with theproduct, situation, and the species andlife stage of invertebrate. Neonicotinoidinsecticides can translocate to owers

and poison natural enemies and pol-linators that feed on nectar and pollen.Delay systemic insecticide applicationuntil after plants have completed theirseasonal owering, unless the productlabel directs otherwise. Where otherplants grow near treated plants, thoseother plants may also take up some ofthe soil-applied insecticide or becomecontaminated with insecticide spraydrift. Delay soil application or foliarspraying of systemics when possibleuntil the nearby plants are also doneowering.

To avoid tree injury and potentialspread of pathogens on contaminatedtools, use a soil application or trunkspray whenever possible instead of in-

jecting or implanting trees with insec-ticide. Injecting or implanting trunksor roots injures trees, and it is dicultto repeatedly place insecticide at theproper depth. If injecting or implantingmultiple trees, prevent the potential Figure 13. Common introduced (or exotic) psyllids in California.

Acacia psyllid nymph Asian citrus psyllid nymphs Acacia psyllid adult

Asian citrus psyllid infestation Bluegum psyllid adult Bluegum psyllid nymphs and eggs

Bluegum psyllid eggs Eugenia psyllid adult Eugenia psyllid nymphs

Eugenia psyllid eggs Laurel psyllid nymphs Olive psyllid adult

Peppert ree psy lli d adu lt Peppert ree psy lli d nymphs Peppertree psyllid egg

Pittosporum psyllid nymphs Redgum lerp psyllid adult and eggs Redgum lerp psyllid nymphs

Redgum lerp psyllid covers andlady beetle larva

Spottedgum lerp psyllid adultRedgum lerp psyllid life stages



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AUTHORS: J. N. Kabashima, UCCooperative Extension, Orange and Los

Angeles Counties; T. D. Paine, Entomology,

UC Riverside; K. M. Daane, UC Berkeley, and

S. H. Dreistadt, UC Statewide IPM Program,

Davis.

TECHNICAL EDITOR: M. L. Flint

EDITOR: K. Beverlin

ILLUSTRATIONS: Figs. 1, 3–5, 7–11. J. K.

Clark; Fig 2: D. Rosen; Fig. 6: M. E. Rogers,

University of Florida; Fig. 12: C. M. Dewees;

Fig. 13: G. Arakelian, J.K. Clark, D.-H. Choe,

M. Johnson, L. Strand.

This and other Pest Notes are available at

www.ipm.ucanr.edu.

For more information, contact the University of

California Cooperative Extension ofce in your

county. See your telephone directory for addresses

and phone numbers, or visit http://ucanr.org/ce.cfm.

WARNING ON THE USE OF CHEMICALS Pesticides are poisonous. Always read and carefully follow all precautions and safety recommendationsgiven on the container label. Store all chemicals in the original, labeled containers in a locked cabinet or shed,away from food or feeds, and out of the reach of children, unauthorized persons, pets, and livestock. Pesticides applied in your home and landscape can move and contaminate creeks, rivers, and oceans.Conne chemicals to the property being treated. Avoid drift onto neighboring properties, especially gardenscontaining fruits or vegetables ready to be picked. Do not place containers containing pesticide in the trash or pour pesticides down the sink or toilet. Either usethe pesticide according to the label, or take unwanted pesticides to a Household Hazardous Waste Collection

site. Contact your county agricultural commissioner for additional information on safe container disposal andfor the location of the Household Hazardous Waste Collection site nearest you. Dispose of empty containersby following label directions. Never reuse or burn the containers or dispose of them in such a manner thatthey may contaminate water supplies or natural waterways.

ANR NONDISCRIMINATION AND AFFIRMATIVE ACTION POLICY STATEMENT

It is the policy of the University of California (UC) and the UC Division of Agriculture & NaturalResources not to engage in discrimination against or harassment of any person in any of its programsor activities (Complete nondiscrimination policy statement can be found at http://ucanr.edu/sites/anrstaff/les/183099.pdf).

Inquiries regarding ANR’s nondiscrimination policies may be directed to Linda Marie Manton, Afrmative Action Contact, University of California, Agriculture and Natural Resources,2801 Second Street, Davis, CA 95618, (530) 750-1318.

Produced by UC Statewide

Integrated Pest Management Program

University of California, Davis, CA 95618-7774

University of California scientists and otherqualied professionals have anonymously peerreviewed this publication for technical accuracy.The ANR Associate Editor for Pest Managementmanaged this process. To simplify information, trade names of productshave been used. No endorsement of named productsis intended, nor is criticism implied of similar productsthat are not mentioned. This material is partially based upon worksupported by the Extension Service, U.S. Departmentof Agriculture, under special project Section 3(d),Integrated Pest Management.

spread of pathogens on contaminatedtools. Before moving to work on eachnew tree, scrub any plant sap from toolsor equipment that penetrate trees anddisinfect them with a registered disin-fectant (e.g., bleach). Avoid methods thatcause large wounds, such as implantsplaced in holes drilled in trunks. Do notimplant or inject roots or trunks morethan once a year.

Insecticides to Avoid. Carbamates(such as carbaryl), the systemic organo-phosphate acephate (Lilly Miller Ready-to-Use Systemic, Orthene), nonsystemicorganophosphates (malathion), and py-rethroids (uvalinate, permethrin) alsocan be applied. Except for infestationsof the Asian citrus psyllid, these insecti-

cides are not recommended. These mate-rials are highly toxic to natural enemiesand pollinators and can cause outbreaksof spider mites or other pests. Becausetheir use in landscapes and gardenscan run or wash o into storm drainsand contaminate municipal wastewater,these insecticides are being found insurface water and are adversely aect-ing nontarget, aquatic organisms.

REFERENCES

Dahlsten, D. L., D. L. Rowney, W. A.Copper, R. L. Tassan, W. E. Chaney, K.L. Robb, S. Tjosvold, M. Bianchi, andP. Lane. 1998. Parasitoid wasp controls blue gum psyllid. Calif. Agric. 52(1):31–34. Available online at http://califor-niaagriculture.ucanr.edu.

Dahlsten, D. L., K. M. Daane, T. D. Paineet al. 2005. Imported parasitic wasphelps control redgum lerp psyllid. Calif.Agric. 59(4): 229–234. Available online athttp://californiaagriculture.ucanr.edu.

Dreistadt, S. H., J. K. Clark, and M. L.

Flint. Pests of Landscape Trees and Shrubs:An Integrated Pest Management Guide. 2004. Oakland: Univ. Calif. Agric. Nat.Res. Publ. 3359.

Grafton-Cardwell, E. E., and M. P.Daugherty. 2013. Asian Citrus Psyllid andHuanglongbing Disease. Univ. Calif. Agric.Nat. Res. Publ. 8205. Oakland. Availableonline at www.ipm.ucanr.edu/PMG/PESTNOTES/pn74155.html.

Halbert, S. E., R. J. Gill, and J. N. Nisson.2006. Eucalyptus Psyllid, Blastopsyllaoccidentalis Taylor and Red Gum LerpPsyllid, Glycaspis brimblecombei Moore (Insecta: Hemiptera: Psyllidae). Universi-ty of Florida Publ. EENY-306. Available

online at http://edis.ifas.u.edu/in583.

Hoddle, M. S. 2013. Invasive Species.Riverside: UC Center for Invasive Spe-cies Research. Available online at http://cisr.ucr.edu/invasive_species.html.

Paine, T. D., S. H. Dreistadt, and J. G.Millar. 2009. Pest Notes: EucalyptusLonghorned Borers. Oakland: Univ. Calif.Agric. Nat. Res. Publ. 7425. Availableonline at www.ipm.ucanr.edu/PMG/PESTNOTES/pn7425.html.

Paine, T. D., S. H. Dreistadt, R. W. Gar-rison, and R. Gill. 2006. Pest Notes: Eu-

calyptus Redgum Lerp Psyllid. Oakland:Univ. Calif. Agric. Nat. Res. Publ. 7460.Available online at www.ipm.ucanr.edu/PMG/PESTNOTES/pn7460.html.

Percy, D. M., A. Rung, and M. S. Hoddle.2012. An annotated checklist of the psyl-lids of California (Hemiptera: Psylloidea).Zootaxa 3193: 1–27. Available online atwww.mapress.com/zootaxa.

Rust, M. K., and D. -H. Choe. 2012. Pest

Notes: Ants. Oakland: Univ. Calif. Div.Agric. Nat. Res. Publ. 7411. Availableonline at www.ipm.ucanr.edu/PMG/PESTNOTES/pn7411.html.

http://www.ipm.ucanr.edu/


http://ucanr.org/ce.cfm


http://ucanr.edu/sites/anrstaff/files/183099.pdf


http://californiaagriculture.ucanr.edu/



http://www.ipm.ucanr.edu/PMG/PESTNOTES/pn74155.html


http://edis.ifas.ufl.edu/in583


http://cisr.ucr.edu/invasive_species.html






http://www.mapress.com/zootaxa

















psyllids mgmt

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