Presentation on theme: "Phytophthora ramorum: Educate to Detect (PRED) University of Illinois Extension in cooperation with USDA-Forest Service USDA-Cooperative State Research."— Presentation transcript:
1 Phytophthora ramorum: Educate to Detect (PRED) University of Illinois Extension in cooperation with USDA-Forest Service USDA-Cooperative State Research Education & Extension Service IPM Regional Centers National Plant Diagnostic Network USDA-Animal and Plant Health Inspection ServiceSlide 1. Monica David’s sectionWelcome to the Phytophthora ramorum (Fi-TOFF-thor-uh ruh-MOR-um): Educate to Detect, or PRED, program. The purpose of the program today is to (1) train first detectors to determine if P. ramorum samples should be taken; (2) to be able to knowledgeably ask a series of questions to rule out false negative cases; and (3) to handle suspect Phytophthora ramorum-infected plants so that they can be collected and sent to the appropriate plant diagnostic lab for testing, if necessary. This program is offered by the University of Illinois Extension in cooperation with the USDA Forest Service,the USDA CSREES Regional Integrated Pest Management Centers, the National Plant Diagnostic Network and the USDA-Animal and Plant Health Inspection Service (APHIS).
2 Overview Introduction History of P. ramorum Symptoms and look-alikes 2IntroductionHistory of P. ramorumSymptoms and look-alikesRegulations and managementSample collection and handlingQuestions and answersSlide 2. Introduction and OverviewMy name is Monica David, and I am the University of Illinois Extension Master Gardener Coordinator and co-chair of the Illinois Sudden Oak Death/P. ramorum blight Task Force. Presenting with me today are Bruce Paulsrud, Extension Specialist in Plant Pathology and Pesticide Safety Education and my co-chair of the task force as well as Nancy Pataky, University of Illinois Plant Clinic Director. For the next hour or so we will be talking with you about Phytophthora ramorum, a pathogen of many trees, shrubs and other plants, and introducing you to the PRED Program as well as the Illinois Detection and Response Plan . We’ll cover the background of Phytophthora ramorum, and the typical symptoms and other disorders that can be confused with Phytophthora ramorum. We’ll also briefly cover regulations and management of this pathogen and how to screen incoming inquiries to identify which samples should be collected and sent to the University of Illinois Plant Clinic. The presentation will also cover how to collect a specimen securely and what will happen to that sample once it gets to the lab. After a brief question and answer period we will conclude with an update on invasive insects by Phil Nixon, University of Illinois Extension Entomologist.There are 41 sites across Illinois participating this morning and we’ll be covering quite a bit of information. If you need something clarified, please tell us immediately. Otherwise, please hold your questions until the question and answer period.Today’s participants should have a copy of the Illinois Detection and Response plan as well as an evaluation for the session. The Illinois plan will be available at by the end of March.
3 Illinois Task Force Co-chairs: Monica David- U of I Extension 3Illinois Task ForceCo-chairs: Monica David- U of I ExtensionBruce Paulsrud- U of I ExtensionDave Bender- IL. Nurseryman’s AssociationMark Cinnamon-IL. Dept of AgricultureSteve Knight- IL. Plant Health DirectorDick Little- IL. Forestry Development CouncilKarel Jacobs- Morton ArboretumEdith Makra- Morton ArboretumNancy Pataky- U of I Plant ClinicDave Shiley- U of I ExtensionSlide 3: Illinois Task Force MembersIn the summer of 2004, the USDA, IPM Regional Directors and the National Plant Diagnostic Network Coordinators contacted each states’ IPM Coordinator and Master Gardener Coordinator regarding a nationwide effort to educate responders and prevent further spread of this pathogen. It was requested that each state create a task force to draft a statewide response plan. The Illinois Task Force was created with members from these Illinois agencies. Representatives of the task force as well as Extension educators participated in a national educational Telenet last fall-similar to the presentation being given today. Illinois Task Force members have also worked to put together the Detection and Response Plan that you have in hand. The committee has worked to publicize awareness of this training session and to begin to educate first responders in Illinois about this potential problem.
4 History outline Status in North American forests Status in Europe 4Status in North American forestsStatus in EuropeStatus in North American landscapes and nurseriesSlide 4. History OutlineI’ll begin with the history and background of Sudden Oak Death and Phytophthora ramorum, including the current status in forests and nurseries in North America and Europe.
5 Marin County, CA (north of San Francisco) 5Slide 5: [Tanoaks in Marin County, 2000]In the mid 1990s, hikers noticed tanoaks (Lithocarpus densiflorus) dying suddenly in three counties along the central coast of California - Marin, Santa Cruz and the Big Sur area of Monterey County. The canopies of these trees appeared to turn brown in a matter of weeks. A few years later a similar phenomenon was seen occurring in coast live oaks (Quercus agrifolia) and California black oaks (Quercus kellogii). As the infested area expanded and more trees died, scientists began to investigate the mysterious tree deaths.Marin County, CA (north of San Francisco)Photo: Marin County Fire Department
6 Marin County, CA (north of San Francisco), 2000 6Slide 6: Oaks in Marin neighborhood [2000 McNears neighborhood]The affected trees were primarily seen along the urban-wildland interface, where homes had been built in wooded areas. This brought many people in close contact with the disease. The dying trees reduced the aesthetic value of their homes and natural areas, and the dead trees also created hazards (falling and fire, for example). As the search for a cause continued, the name “Sudden Oak Death” was coined. The infested area continued to grow and there was concern of an epidemic in California’s oaks.Marin County, CA (north of San Francisco), 2000Photo: Marin County Fire Department
7 Phytophthora ramorum Sporangia releasing zoospores 7Phytophthora ramorumSporangia releasing zoosporesSlide 7. [Phytophthora ramorum in culture]In the summer of 2000, plant pathologists at the University of California isolated the organism causing the deaths of the tanoaks and oaks. It was an unrecognized Phytophthora species. They soon learned that this species had been previously observed when it was isolated from diseased rhododendrons and viburnums in European nurseries in The species eventually became known as ramorum – Latin for “branches.” Phytophthoras are water molds and are most active during humid or wet conditions. They produce spores that can swim through water. Some Phytophthoras also produce spores that can be spread by wind if conditions are not too hot and dry.Phytophthora ramorum in culturePhoto: UC Davis & UC BerkeleyChlamydospores
8 Photo: Joseph O’Brien, USDA-Forest Service 8Slide 8. Foliar symptomsKnowing that the pathogen was found on the leaves of nursery plants in Europe, researchers went back into the affected California forests. There, P. ramorum was soon isolated from more plant species, including California bay laurel (Umbellularia californica). The symptoms on CA bay laurel and other “foliar hosts” were limited to leaf spots and shoot dieback.Phytophthora ramorum infection on the leaves of California bay laurel (Umbellularia californica)Photo: Joseph O’Brien, USDA-Forest Service
9 Two sets of symptoms caused by Phytophthora ramorum 9Two sets of symptoms caused by Phytophthora ramorumSudden Oak DeathRed oak group hosts and tanoakStem lesions beneath the barkMay bleed or oozeCan kill adult plantsPhytophthora ramorum Foliar BlightNon-oak hostsSpots and blotches on leavesShoot diebackCan kill juvenile plants, occasionally mature plantsSlide 9. Two sets of symptomsThere are two distinct sets of symptoms caused by the Sudden Oak Death pathogen. The species of host plant determines which symptoms develop. The disease called “Sudden Oak Death” is the result of lethal stem cankers in the inner bark that expand and girdle the stem, killing the tree. Certain members of the oak family exhibit these symptoms. Foliar blight and shoot dieback are more typical symptoms on many of the other host species.
10 Photo: Mike McWilliams, ODF 10Slide 10. Oregon, Curry County 2001Now back to our chronology. P. ramorum was discovered in Oregon via aerial survey in the summer of P. ramorum was killing tanoaks in Curry County, in the southwest portion of the state, just across the border from CA. Oregon immediately quarantined the area and attempted to eradicate the pathogen by clear-cutting and burning infested areas.Photo: Mike McWilliams, ODF
11 P. ramorum confirmations in forests 11P. ramorum confirmations in forestsSlide 11. Map of infected forestsIn natural forest settings, the disease is currently found in 14 California counties, shown here in red, scattered along the coast from Monterey County north toward Oregon. The Oregon quarantine area is an 11.5 square mile area. In all, approximately 60 acres have been cleared and burned in Oregon over the past 3 years. As of October 2004, the infection in wildland forests is not known to occur anywhere else in United States.Map fromKelly, UC-Berkeley
12 Map: USDA- Forest Service 12Slide 12. [Risk map of entire US]This map shows the expected risk of Phytophthora ramorum becoming established in our forests. The degree of risk is based on climate, host range, and proximity to nursery operations. The pathogen is not considered native to North America. When it was introduced to California it was able to establish itself in native forests and kill trees. The concern is that large areas of the US could provide the necessary host plants and suitable climate for the pathogen to become established and kill trees. We’ve seen this happen with Dutch elm disease and chestnut blight.Map: USDA- Forest Service
13 European garden & nursery finds 13European garden & nursery findsSlide 13. [European nurseries I – infected rhododendrons]While we were learning more about how the pathogen operates in west coast forests, nurseries and gardens throughout Europe were reporting P. ramorum on rhododendron, camellia, and other nursery stock. Upon laboratory comparison, the pathogen in Europe was identified as the same species but a different population and mating type than the pathogen isolated in California and Oregon. The European population is generally considered to be more aggressive on nursery plants than the North American population. In December 2002, the European Union issued a quarantine which required member states to survey for P. ramorum. The pathogen was isolated from nurseries in the UK, Netherlands, Spain, and many other European countries. Despite quarantine efforts, nursery infestations in the UK became quite widespread. The affected nursery stock and garden plants included Rhododendron, Viburnum, Camellia, Pieris, Kalmia latifolia (mountain laurel), Arbutus (strawberry tree), Syringa (lilac), Taxus baccata (yew), and Hamamelis (witch hazel).Phytophthora ramorum infection on rhododendron in EuropePhoto: Hans DeGruyter, Netherlands Plant Protection Institute
14 Infected trees in Europe 14Infected trees in EuropeSlide 14. [European wildland finds]In December 2003, the UK and Netherlands reported that P. ramorum was infecting the trunks of beech (Fagus sylvatica) southern red oak (Quercus falcata) northern red oak (Quercus rubra) and horse chestnut (Aesculus hippocastanum). In all cases, the infected trees are located near P. ramorum-infected rhododendrons.Quercus rubraFagus sylvaticaPhoto: DEFRA
15 Photo: Jennifer Parke, Oregon State University 15Slide 15. [North American nurseries I]Until 2004, many considered P. ramorum in nurseries to be an European issue. There were a few detections in west coast nurseries. For example, in 2001, rhododendron in a California nursery was confirmed as infected with P. ramorum – but it was surrounded by a heavy forest infestation. Then, in 2003, 17 nurseries on the west coast of the US and Canada were found positive for P. ramorum (8 CA, 6 OR, 2 WA and 1 BC). Trace-forwards and trace-backs were conducted to determine the source and fate of the infected plants, and diseased plants were destroyed. Some of the affected nurseries in Oregon and Washington were found to have both the North American and European population genotypes. If the European and North American populations combine to form new strains, they could be more virulent, so this is of particular concern.Photo: Jennifer Parke, Oregon State University
16 Photo: Jonathan Jones, APHIS, PPQ 16Slide 16. [North American nurseries II]In February 2004, P. ramorum was detected on plants at this large nursery in southern California. The nursery is over 400 miles from the nearest known infested forest. The climate in the vicinity of the nursery is usually hot and dry, and disease symptoms became apparent only after a period of heavy rain. Disease was particularly severe in small liners (see inset, bottom right).Photo: Jonathan Jones, APHIS, PPQ
17 Trace-forward & trace-back investigations 17Trace-forward & trace-back investigationsTrace forwards = to the nurseries where stock was shipped TO Trace backs = to the nursery where stock was shipped FROMSlide 17. [Trace backs and trace forwards]When P. ramorum is detected in a nursery, the USDA-APHIS, in cooperation with state agriculture departments and others, places the host material on hold and investigates further to determine the extent of the infestation and eradicate it. Infected plants and neighboring plants are destroyed. At one nursery in Southern California over 1 million camellias were destroyed.The shipping records of the infested nursery are checked and officials from state agriculture and APHIS are notified of all host shipments from that nursery for 1 year prior to the detection. Investigations of where the potentially infected stock was shipped TO are called “trace forwards” and investigations of where the stock originated FROM are called “trace backs.” In 2004, over 1.6 million plants were investigated by states and APHIS to check for infections and destroy them. Unfortunately, many of the plants were sold prior to the investigation – that is why we are trying to track down those plants through this PRED program and are asking for your help.
18 Phytophthora ramorum national survey 18Phytophthora ramorum national surveyMost states have started or completed their surveysOver 3,000 nurseries / garden centers have been surveyedOver 50,000 samples have been takenOriginally 15 positives in 7 statesAll samples taken in Illinois were negativeSlide 18.[ National Survey]APHIS and the departments of agriculture in each state initiated a national survey of nurseries for Phytophthora ramorum. As of fall 2004, over 3000 nurseries were surveyed and over 50,000 samples taken, which originally resulted in 15 finds in 7 states. The USDA-Forest Service is cooperating with APHIS and the States on a national P. ramorum wildlands survey as well. Of the 1.6 million potentially infected plants that were shipped, it is estimated that about 11,000 plants infected with P. ramorum were sold.In Illinois, state inspectors checked all of the recipient nurseries and suspect plants were sampled and tested for Phytophthora ramorum at the University of Illinois Plant Clinic. All samples from trace-forward inspections were found to be negative.
19 19 Slide 19 [Survey Findings] As of January 10, 2005, the nationwide survey has now identified 176 confirmed positives in 22 states. Plants have been destroyed in an attempt to eradicate the pathogen in all cases. However, some plants were sold before inspection. There is a risk that the pathogen may move from infected nursery stock planted in the landscape to nearby native forest vegetation.
20 Symptoms & look-alikes 20Sudden Oak Death on oak hostsSymptoms on other hostsScreening questions at the NCIPM website (www.ncipm.org/sod) and in the Illinois plan:focus on recently purchased (or near recently purchased) camellia, kalmia, lilac, pieris, rhododendron, or viburnumSlide 20. Nancy Pataky’s sectionSymptoms of Phytophthora ramorum and look-alikesThe goal of the PRED program is to show you how you can help the regulatory agencies and diagnostic labs find any additional infected plants in our landscapes and wildlands. In this section we will go over P. ramorum symptoms and common look-alikes, both on oaks and foliar hosts. By reviewing both symptoms and look-alikes, we hope to provide you the background information necessary to determine whether a plant sample should be sent to a lab for diagnosis. A set of screening questions has also been developed to help with this process. We will return to the screening questionnaire later in the presentation, but be sure to also review the questionnaire directly at the NCIPM website or look at the modified questionnaire in the Illinois Sudden Oak Death / Phytophthora ramorum blight Detection and Response plan.
21 Symptoms caused by P. ramorum differ on different hosts 21Symptoms caused by P. ramorum differ on different hostsSudden Oak Death affects members of the oak family (Fagaceae)Slide 21.Disease symptoms caused by Phytophthora ramorum differ on different hosts. Sudden Oak Death describes the disease on certain members of the oak family (Fagaceae), including true oaks, tanoak, chestnut, and beech. In Illinois and other Midwestern states the concern is that Sudden Oak Death might infect our oaks, especially the red oak group. Members of the white oak subgenus so far have not become naturally infected. Tanoak is a species that does not grow in Illinois landscapes.True oaks (Quercus spp.)Tanoak (Lithocarpus densiflorus)Chestnut (Castanea) [Europe only]Beech (Fagus) [Europe only]
22 P. ramorum on coast live oak 22P. ramorum on coast live oakSlide 22.The term Sudden Oak Death describes the rapid onset of crown death that can occur on members of the oak family. This slide shows a coast live oak forest in California affected by P. ramorum.Photo: Pavel Svihra, UC Cooperative Extension
23 ‘Bleeding’ canker on tree trunk 23‘Bleeding’ canker on tree trunk‘Bleeding’ or oozing on the barkNot associated with cracks in bark or insect holesUsually on the lower 6 ft. of tree trunksSlide 23.Upon closer examination, P. ramorum-infected trees with widespread crown death show symptoms of bleeding bark on the trunk. Bleeding on the bark is an oozing or seeping of a reddish-brown to tar black sap that appears as small droplets on the bark. This is the tree’s response to infection or injury and is not unique to P. ramorum. Bleeding caused by P. ramorum is typically not associated with cracks in the bark or insect holes, although insect holes may be present in P. ramorum infected trees. Bleeding cankers usually occur first in the lower portion of tree trunks but have been found as high as 60 ft. above the ground. The combination of whole crown death accompanied by bleeding of the bark are good indicators of P. ramorum infection.Photo: Garbelotto lab, UC Berkeley
24 Phytophthora ramorum “bleeding” 24 Slide 24.On the top and bottom left are trees with active bleeding cankers. On the right is a tree in which the infection is older and the bleeding is less active. The bleeding has been washed away by rainfall leaving diffuse stains on the bark.Photos: Mike McWilliams, ODF & Bruce Moltzen, Missouri Dept. of Conservation
25 Phytophthora ramorum25Slide 25.This photo is from a coast live oak. If you shave off the outer layer of bark where the bleeding is present, you will see the cankers in the inner bark. The cankers are infected tissue which appear as dark blotches surrounded by black lines. In this species, healthy bark is bright red. Infected bark is brownish and surrounded by a dark line. This is not a species that grows in Illinois but similar symptoms may occur on infected Illinois oaks.Cankers (in inner bark) are surrounded by a black linePhoto: Dave Rizzo, UC Davis
26 Phytophthora ramorum 26 outer bark inner bark Slide 26.This slide shows symptoms caused by P. ramorum on tanoak. On the left is a photo of the outer bark, showing the bleeding canker caused by P. ramorum. On the right is the same tree with the outer bark removed to reveal the inner bark under the bleeding. In this species, the healthy bark is bright red. In the next few slides, we’ll be looking at similar symptoms on the outer and inner bark caused by fungi or insects.outer barkinner barkPhoto: Bruce Moltzen, Missouri Department of Conservation
27 Similar symptoms – not P. ramorum 27Similar symptoms – not P. ramorumSlide 27.This bleeding canker on the left is caused by a fungus, Armillaria, a root pathogen. On the right, note the white mycelial fans under the bark as shown by the white arrow. If you see only these symptoms, it is not P. ramorum. Also, cankers caused by P. ramorum, generally do not extend down below the soil line, but those caused by Armillaria begin beneath the soil line at the base of the tree and grow upward. Sometimes trees can be infected by both Armillaria and P. ramorum, however. Armillaria is a common tree disease in the Midwest.outer barkinner barkBleeding canker caused by ArmillariaPhoto: Steve Oak, USDA-Forest Service
28 Similar symptoms – not P. ramorum 28Similar symptoms – not P. ramorumSlide 28.This bleeding canker on the left is caused by an insect that has bored through the inner bark shown on the right. It is not Phytophthora ramorum.outer barkinner barkBleeding canker caused by inner-bark boring insectPhoto: Steve Oak, USDA-Forest Service
29 Similar symptoms – submit sample 29Similar symptoms – submit sampleSlide 29.This bleeding canker on the left is caused by a fungus, Inonotus hispidus (formerly Polyporus hispidus) . However, the inner bark symptoms are similar enough to those caused by P. ramorum that the tree should be tested. Inonatus is a wood-rotting fungus found on several tree species in the Midwest. outer barkinner barkBleeding canker caused by Inonotus hispidusPhoto: Steve Oak, USDA-Forest Service
30 Similar symptoms – not P. ramorum 30Similar symptoms – not P. ramorumSlide 30.Oak wilt can cause rapid death of oaks in the Midwest, especially trees in the red oak group. Oak wilt does not cause bleeding cankers although cankers may occur with oak wilt. Look for vascular streaking on branches infected with the oak wilt fungus.Scorching of foliage and vascular discoloration typical of Oak Wilt
31 Similar symptoms – not P. ramorum 31Slide 31.Bacterial leaf scorch (BLS) has been found on oak in Illinois in recent years. This disease causes progressive scorching that may be fatal. BLS does not cause bleeding cankers.Scorching of foliage caused by Bacterial Leaf Scorch
32 Other common diseases & injuries 32Other common diseases & injuriesBacterial wetwoodBoring insectsMechanical injuryFungiSlide 32.There are many other tree diseases, injuries and disorders that can cause similar symptoms, and this can be confusing when trying to diagnose Sudden Oak Death. A few of the more common causes are bacterial wetwood, insects, mechanical injury, fungi, and even other Phytophthora species, such as Phytophthora cinnamomi. If you are in doubt about what is causing a bleeding canker, seek the advice of an expert in your area, such as your county extension agent or the University of Illinois Plant Clinic.
33 On other plant hosts, P. ramorum causes symptoms of foliar blight 33On other plant hosts, P. ramorum causes symptoms of foliar blightPyracanthaHoneysuckleYewDouglas-firGrand firCoast redwoodCamelliaRhododendronViburnumPierisMountain laurelLilacSlide 33.On plant hosts not in the oak family, Phytophthora ramorum causes different symptoms – Foliar blight involving leaves and sometimes shoot dieback. We should call this ramorum blight or ramorum dieback, not Sudden Oak Death. Examples of plant hosts that exhibit foliar blight and/or shoot dieback include camellia, rhododendron, viburnum, pieris, mountain laurel (kalmia), and lilac. These are common ornamental species that are sold in nurseries and planted in residential yards all over the U.S. Some conifers can also show foliar blight on young growth. Grand fir and Coast redwood, listed here, do not normally grow in Illinois landscapes.
34 34Symptoms on camelliaSlide 34.Camellia plants infected with P. ramorum were shipped to almost every U.S. state during the last year or two. Symptoms on camellia vary depending on the cultivar of camellia, and the environmental conditions under which camellias are grown. The slides with the black background show different camellia cultivars in California infected with P. ramorum. The brown lesions can be irregular in shape or restricted to the leaf tip. Under humid conditions, the edges of the lesion are less distinct, as shown in the photo of a camellia leaf in Oregon in the bottom right.Top left: Camellia ‘Kramer’s Supreme’ – Blomquist photoTop right: Camellia “Mr. Charles Cobb’ – Blomquist photoBottom left: Camellia ‘Silverwaves’- Blomquist photoBottom right: Camellia from Oregon Dept. of AgriculturePhotos: Oregon Dept. of Agriculture & Cheryl Blomquist, CDFA
35 Symptoms on camellia 35 Photo: Cheryl Blomquist, CDFA Slide 35. On this camellia, note the irregular brown lesions on the larger leaf, and lesions on the leaf tips on the smaller two leaves. The lower leaves on the plant tend to show symptoms most readily. Sometimes the infected leaves fall off prematurely, leaving lower stems with few leaves as shown here.Photo: Cheryl Blomquist, CDFA
36 Symptoms on camellia Symptoms can be subtle 36Symptoms can be subtleLook for irregular-shaped brown lesions on the leavesSometimes only the tips of leaves are brownLook for lower leaves that have fallen offSlide 36.Symptoms on camellia can be subtle and difficult to see. Look for irregular-shaped brown lesions on the lower leaves or brown leaf tips, as well as infected fallen leaves.Photo: Cheryl Blomquist, CDFA
37 Similar symptoms – submit sample 37Similar symptoms – submit sampleSlide 37.Other pathogens or abiotic disorders can cause lesions on camellia leaves, and this can be confusing. Look at where the symptoms occur on the plant. If the symptoms are uniformly distributed all over the plant, or only where the leaves are exposed to full sun, it is probably not a disease. This camellia sample has symptoms of sun scorch, not P. ramorum. If in doubt, samples should be submitted for testing, especially if the camellia was purchased since 2002.Sun scorch on camelliaPhoto: Carrie Harmon, University of Florida
38 Similar symptoms – submit sample 38Similar symptoms – submit sampleSlide 38.These camellia plants show the results of cold injury. Again, if the camellia leaf symptoms are similar to those caused by P. ramorum and you cannot rule out other causes, you should submit a sample for laboratory tests. This is particularly true if the camellia was purchased since 2002.Cold injury on camelliaPhoto: Richard Regan, Oregon State University
39 P. ramorum symptoms on rhododendron 39Slide 39.Phytophthora ramorum can infect both native rhododendrons and horticultural varieties of rhododendron. This slide shows shoot dieback (left) and foliar blight symptoms (center and right) on native Pacific rhododendron in the field. Note the dark discoloration that often follows the leaf midrib or petiole as shown by the white arrows.Shoot diebackFoliar blightFoliar blightRhododendron macrophyllumPhoto: Everett Hansen, Oregon State University
40 P. ramorum symptoms on rhododendron 40Slide 40.In this case it appears that the infection has moved from the shoot tip into the leaves.Rhododendron macrophyllumPhoto: Everett Hansen, Oregon State University
41 P. ramorum symptoms on rhododendron 41P. ramorum symptoms on rhododendronSlide 41.In the nursery, horticultural varieties of rhododendron infected with P. ramorum can develop symptoms like these.Photo: Bruce Moltzen, Missouri Dept. of Conservation
42 P. ramorum symptoms on rhododendron 42Slide 42.P. ramorum symptoms may also occur where water (and spores) remain on the leaves for several hours. Note the brown lesions along the edges of the leaves where the water accumulated.Rhododendron ‘Unique’Photo: Jennifer Parke, Oregon State University
43 P. ramorum symptoms on eastern native rhododendrons (inoculation trials)43Slide 43.Infections on eastern native species of rhododendron have not been found in the wild, but artificial inoculation experiments in the greenhouse show us what symptoms may look like on these species.Photo: Paul Tooley, USDA-ARS
44 Similar symptoms – submit sample 44Similar symptoms – submit sampleSlide 44.There are several other species of Phytophthora that commonly infect rhododendron leaves and cause symptoms similar to those caused by P. ramorum. In this photo, disease is caused by Phytophthora syringae. Lab tests are necessary to identify the species of Phytophthora that cause foliar blight. If you see symptoms like these, submit a sample to determine if it is P. ramorum.Foliar blight caused by Phytophthora syringaePhoto: Jay Pscheidt, Oregon State University
45 Similar symptoms – submit sample 45Similar symptoms – submit sampleSlide 45.Here are photos of rhododendrons in a North Carolina nursery infected with other species of Phytophthora. If you see a plant with similar symptoms – especially if it has been purchased since 2002 – submit a sample for testing.Foliar blight caused by Phytophthora speciesPhoto: Mike Benson, NCSU
46 Similar symptoms – not P. ramorum 46Slide 46.Several Phytophthora species can also cause root disease on rhododendron. The wilted plants in the foreground show symptoms of root disease, not leaf blight. If the whole rhododendron plant rapidly wilts and dies, it is likely caused by a root-infecting species of Phytophthora. Phytophthora root rot is a common disease on rhododendron in Illinois, especially in wet or poorly drained sites. Phytophthora ramorum is not known to cause root disease in a natural setting or in nurseries.Phytophthora root rot - not caused by P. ramorumPhoto: Jay Pscheidt, Oregon State University
47 Similar symptoms – not P. ramorum 47Slide 47.Not all brown spots on rhododendrons are caused by Phytophthora. On the left is a leaf with symptoms of sun scorch. Note the brown spot in the center of the leaf which does not extend along the midrib or petiole. Sun scorched leaves are susceptible to gray blight (Pestalotiopsis sydowiana), which gives the leaves a silvery look (right). Rhododendron leaves that look like this do not need to be submitted for sampling for P. ramorum.Sun scorchGray blight can develop on sun scorched rhododendron leavesPhoto: Rich Regan, Oregon State University
48 Symptoms on pieris Pieris japonica 48 Slide 48.There are several species and hybrids of pieris, sometimes called andromeda. The young leaves and shoots of pieris are quite susceptible to infection by P. ramorum. Symptoms are brown discoloration of the young leaves and shoots.Pieris japonicaPhoto: Oregon Dept. of Agriculture
49 P. ramorum symptoms on pieris 49Slide 49.Note the symptoms of P. ramorum foliar blight and shoot dieback on the youngest tissue at the top of the plant. An older leaf on the bottom right has somewhat different symptoms.Pieris japonicaPhoto: Oregon Dept. of Agriculture
50 P. ramorum symptoms on viburnum 50Slide 50.Several species of viburnum are hosts for Phytophthora ramorum. Symptoms include shoot dieback, leaf blight, and stem canker.Viburnum x bodnantense ‘’Dawn’Photo: Oregon Dept. of Agriculture
51 P. ramorum symptoms on viburnum 51Slide 51.Severe disease results in wilting of the leaves and/or defoliation. This can be hard to see if plants are crowded together, like these plants in a nursery.Viburnum x bodnantense ‘Dawn’Photo: Oregon Dept. of Agriculture
52 P. ramorum symptoms on viburnum 52Slide 52.Brown, ‘watersoaked’ leaf spots indicate initial symptoms of ramorum foliar blight on this viburnum.Viburnum plicatum tomentosum ‘Mariesii’Photo: Jennifer Parke, Oregon State University
53 P. ramorum symptoms on viburnum 53stem cankerSlide 53.Stem canker has also been observed on viburnum.Photo: Sabine Werres, Institute für Pflanzenschutz im Gartenbau, Germany
54 P. ramorum symptoms on kalmia (mountain laurel) 54P. ramorum symptoms on kalmia (mountain laurel)Slide 54.Kalmia (mountain laurel) is native to eastern N. America and horticultural cultivars are also widely grown in nurseries. Kalmia is highly susceptible to P. ramorum and should be observed carefully for symptoms of infection. P. ramorum causes irregular-shaped lesions on Kalmia, often associated with the midrib.Photo: DEFRA
55 Similar symptoms – submit sample 55Similar symptoms – submit sampleSlide 55.These leaf spots on Kalmia were caused by another Phytophthora species (P. syringae) but the symptoms are similar to those caused by P. ramorum. Any Kalmia leaves with this symptom should be tested for P. ramorum.Kalmia latifolia (mountain laurel)Photo: Robert Linderman, USDA-ARS
56 Similar symptoms – submit sample 56Similar symptoms – submit sampleSlide 56.Leaf spots on kalmia can be caused by many fungi. These symptoms are not caused by P. ramorum, but they may look similar. Leaves that look like this should be submitted for sampling, especially if they are adjacent to a host plant that was purchased within the last 2 years.Kalmia latifolia (mountain laurel)Photo: Peter Angwin, USDA-Forest Service
57 P. ramorum symptoms on lilac 57P. ramorum symptoms on lilacSlide 57.P. ramorum also causes foliar blight and shoot dieback on lilac.Photo: Alexandra Schlenzig, Scottish Agricultural Science Agency
58 Similar symptoms – submit sample 58Similar symptoms – submit sampleSlide 58.A common disease on lilac is bacterial blight (Pseudomonas syringae pv. syringae). Symptoms of this disease could be confused with leaf blight caused by P. ramorum. If you see symptoms like this – blackened shoots and wilted black leaves – submit a sample for lab diagnosis, especially if the plant was purchased recently.Bacterial blight on lilacPhoto: Jay Pscheidt, Oregon State University
59 P. ramorum symptoms on conifers 59P. ramorum symptoms on conifersSlide 59.Some conifers such as Grand fir, yew, Douglas-fir and redwood are also susceptible to Phytophthora ramorum. Tip blight can develop on young, actively growing shoots, but so far this has been a problem only when young trees are directly beneath heavily-infected oaks or bay trees. Grand fir and bay trees do not grow in Illinois landscapes but other conifers may show these symptoms. Douglas-fir is a commonly grown Illinois evergreen.Grand firDouglas-firPhoto: Santa Clara Co. (CA) Agriculture Dept. & Dave Rizzo, UC Davis
60 Regulations & Management 60P. ramorum quarantinesFederal vs. State quarantinesQuarantine goalsWhat areas are under quarantine?What is the impact of a quarantine? (Why we don’t really want to find out!)P. ramorum management strategiesSlide 60. Bruce Paulsrud’s SectionThis is Bruce Paulsrud, and I will cover P. ramorum regulations, including federal and state quarantines, quarantine goals, the areas currently under Federal quarantine, and then we’ll take a look at what it means to be under a Federal quarantine. I’ll finish by discussing some cultural and chemical strategies that may be useful in the event that P. ramorum reaches Illinois.
61 Phytophthora ramorum regulations & quarantines 61Federal quarantinesAuthorization: Plant Protection ActPrevent movement between statesState quarantinesAuthorization in IL: IL Pest and Disease Act505 ILCS 90 (www.ilga.gov/legislation/ilcs/ilcs.asp)Prevent introductions and movement within a stateSlide 61.Both state and federal quarantines are in effect for P. ramorum. The federal quarantine covers shipments between states. The state quarantines cover shipments within a state and are also designed to prevent pest introduction to the state. California and Oregon currently have P. ramorum quarantines in place. Since P. ramorum has not been found in Illinois there are no quarantined areas within our state. Internationally, USDA-APHIS has also informed the European Commission of restrictions on their member country exports of P. ramorum host plants and propagative material. For information about these acts, contact USDA State Plant Health Director, Steve Knight, or the Illinois Department of Agriculture State Plant Regulatory Official, Mark Cinnamon. Contact information for both individuals is provided in the Response chapter of P. ramorum Detection & Response Plan.
62 Federal P. ramorum quarantine program goals 62Federal P. ramorum quarantine program goalsPrevent the artificial spread of P. ramorumTake the least restrictive action necessaryDetermine status of disease, nationwideKeep the regulations current with the science and riskIdentify where infected items came from and went toClean up infested nurseries and garden centersSlide 62.The goals of the federal quarantine are to: Prevent the artificial spread of P. ramorum; Take the least restrictive action necessary; Determine the status of the disease, nation-wide; Keep the regulations current with the science and risk; Identify where infected items came from and went to; and finally, to clean up infested nurseries and garden centers.
63 Phytophthora ramorum regulations & quarantines 63Federal quarantine areas14 California counties & part of an Oregon county“Pest is present and being officially controlled”P. ramorum is established in natural environment, but within the quarantined area.Federal regulated areasAll of California, Oregon, and Washington“…is subjected to phytosanitary measures”Think of this as a buffer between known infested and non-infested areasSlide 63.The Emergency Federal Order Restricting Movement of Nursery Stock from CA, OR, and WA was published on December, 21, 2004 and is available online. This document lists the quarantined areas and goes further by designating entire states as regulated areas. Fourteen CA counties and part of a county in Oregon are under quarantine. Within the quarantined areas P. ramorum is present, is known to be established in natural areas, and eradication measures are underway. Furthermore, ALL of CA, OR, and WA are treated as “Regulated areas”. This does not mean that these states are completely infested. However, they do serve as a buffer between known infested areas and non-infested areas. All nurseries in a regulated area are inspected annually for P. ramorum.
64 Phytophthora ramorum regulations & quarantines 64Impact on Federal quarantined areas:Each shipment of host or associated host plants or regulated articles must be inspected before shipping interstate – must be free of P. ramorum.Annual inspection - even in nurseries that don’t contain or ship P. ramorum hosts or associated hosts.Slide 64.In a nutshell, this is the immediate impact of a Federal quarantine: Each shipment of host plants, associated host plants, or regulated articles must be inspected before shipping interstate; they must be free of P. ramorum. In addition, an annual inspection of each nursery must take place; even in nurseries that don’t contain or ship P. ramorum hosts or associated hosts.
65 Phytophthora ramorum domestic regulated articles/materials 65Phytophthora ramorum domestic regulated articles/materialsNursery stock*Forest stockWoodBarkSoilWreaths & greenerySlide 65.These are the materials that are subject to quarantine: nursery and forest stock, wood, bark, soil, and wreaths and greenery. P. ramorum infects a wide range of host plants, including trees, shrubs, an herbaceous plant, and a fern. The list of regulated plants for the federal quarantine is updated frequently as new hosts are found. You can access a current host list from the above URL; I’ll show you this URL and website in just a minute.* Seefor a current list of hosts and associated hosts
66 Phytophthora ramorum regulations & quarantines 66Impact on Federal regulated areas:Nurseries may not ship hosts or associated hosts until inspection proves the nursery is not infested with P. ramorum.Annual inspection - even in nurseries that don’t contain or ship P. ramorum hosts or associated hosts.Slide 66.The immediate impact on Federal regulated areas are: 1) Nurseries may not ship hosts or associated hosts until the nursery has been inspected and documented to be free of P. ramorum. And, as with the quarantined areas, an annual inspection of each nursery must take place; even in nurseries that don’t contain or ship P. ramorum hosts or associated hosts.
67 USDA-APHIS website: www.aphis.usda.gov/ppq/ispm/sod 67Slide 67.The best place to get additional detailed information on the federal P. ramorum regulations is at the APHIS Plant Protection Quarantine website. There is much more to the APHIS website and to the P. ramorum page that you see on this slide; it’s a great resource for learning about a variety of new and invasive pests of plants and animals.
68 Prevention & Management 68Prevention & ManagementCultural tactics:Thoroughly inspect all new plants for unusual symptoms prior to introducing them into the nursery, garden center, forest, or landscape.Avoid planting P. ramorum-foliar hosts under or adjacent to oak trees.Avoid wetting the plant foliage, which will stimulate foliar diseases such as P. ramorum.Monitor host plants frequently and promptly submit a sample from any suspicious plant.Slide 68.Plants from P. ramorum -infested nurseries and counties are under are not allowed to enter the channels of trade. Nevertheless, it is always a good practice to thoroughly inspect all plants for unusual disease symptoms and insects prior to introducing them into the nursery, garden center, forest, or landscape. Avoid planting P. ramorum hosts under or adjacent to oak trees. For example, Rhododendron is a commonly planted ornamental that is a host for P. ramorum, and it is possible that an infested rhododendron could infect a nearby oak. Avoid wetting the plant foliage, which will stimulate foliar diseases such as P. ramorum. And finally, monitor host plants for P. ramorum blight symptoms and promptly submit a sample from any suspicious plant.
69 Prevention & Management 69Prevention & ManagementFungicides:Information now emerging: interpret with cautionTwo established active ingredients seem to have the most promise (and data)- mefenoxam (Subdue Maxx): Foliar infections- phosphorous acid (AGRI-FOS): Trunk cankersRegular or supplemental labels are expected soonRead the labels carefullySee the “IL P. ramorum Detection & Response Plan” for further details.Slide 69.Researchers are investigating the usefulness of a number of different fungicides to prevent infection by P. ramorum. The Response chapter of the Illinois P. ramorum Detection and Response Plan goes into more detail, but suffice it to say here that it is wise to use caution when interpreting the efficacy results you find. At this time, the two most well-documented fungicides for preventing P. ramorum are mefenoxam and phosphorous acid. In fact, California and Oregon sought and received Section 24c supplemental labels to allow the use of these fungicides within their states on a limited basis. In the meantime, pesticide registrants have been working to expand their fungicide labels so that all states can use them to prevent P. ramorum on oak and important foliar hosts. Nationwide regular or supplemental labels are expected soon for mefenoxam (which is sold by Syngenta as Subdue Maxx) and also for phosphorous acid (which is sold by AgriChem as AGRI-FOS). Most of the research with mefenoxam has targeted the prevention of foliar infections, while most research with phosphorous acid has focused on preventing trunk cankers.
70 P. ramorum procedures Review of material just presented Goal of PRED 70Review of material just presentedGoal of PREDOverview of the programWhat to do…Slide 70. Nancy Pataky’s sectionNow you have received training on the history of Phytophthora ramorum in the US and Europe. You have also learned that there are a lot of plants in residential landscapes that are potentially infected with P. ramorum. You have learned what the typical symptoms are and how they differ according to host plant. The goal of PRED is to show you how you can help the regulatory agencies and diagnostic labs find any additional infected plants in our landscapes and wildlands. Its focus is on camellia, rhododendron, kalmia, viburnum, Pieris, and lilac. These are the most commonly infected plants in West coast nurseries that have been shipped throughout the US. We are particularly interested in plants that have been purchased since 2002 or are adjacent to such plants and show symptoms of P. ramorum. We will discuss what to do if you encounter clientele with such plants.You should have a copy of the Illinois Sudden Oak Death / Phytophthora ramorum blight Detection and Response plan in front of you. We have covered major points in that plan today. Refer to your copy for details.
71 Sample referral criteria 71Sample referral criteriaPlants likely to be infected by Phytophthora ramorum (as indicated by the screening questionnaire):Affected plant is on host list and purchased since 2002Affected plant is near a recently purchased host plantSymptoms are consistent with Phytophthora ramorumScreening questions at the NCIPM website (www.ncipm.org/sod) or the same questions modified for Illinois and found in the Illinois planSlide 71.A set of screening questions has been developed to help determine which suspect samples should be submitted for laboratory diagnosis. Samples from host plants that were purchased since 2002, or nearby susceptible plants, should be submitted for diagnosis if they exhibit typical symptoms of P. ramorum. Other samples that are very unlikely to have P. ramorum do not need to be submitted for lab diagnosis. The questionnaire, available from the NCIPM website (www.ncipm.org/sod) will guide you through this decision-making process.
72 Communication Submit the suspect sample to: 72CommunicationSubmit the suspect sample to:University of Illinois extension office near youfor DDDI submissionIf still suspect, the sample will need to be sent to: University of Illinois Plant Clinic1401 W. St. Mary’s Rd.Urbana, IL 61802Avoid alarming behavior. Don’t jump to conclusions.Wait for lab resultMaintain confidentialitySlide 72.Take the sample to a nearby University of Illinois Extension office. The sample will be entered into the distance diagnostics through digital imaging system. Extension staff will help take and send images of your samle. Specialists in Illinois will view these images and advise you to send a plant sample to the University of Illinois Plant Clinic for testing or provide an alternate cause of symptoms seen on your sample. It is impossible to confirm P. ramorum at this point. Your sample will be sent for further testing and a diagnosis will be provided to you. You will be contacted as soon as the results are back from the lab.
73 If you’re asked to collect a sample 73If you’re asked to collect a sampleCollect leaves that show various stages of symptom development.Take pictures of symptoms and environment.Slide 73.If you’re asked to collect a sample: Collect leaves that show various stages of symptom development; and if possible take pictures of symptoms and the surrounding vegetation.
74 74Packaging a samplePlace sample on a paper towel. Do not wet the towel.Double bag and seal the sample in zippable bags.If shipping, use a crush proof box with seams sealed completely with tape.Be sure to include the sample submission form required by your state.Slide 74.When packaging a sample: Place sample on a paper towel. Do not wet the towel; Double bag and seal the sample in zippable bags; If shipping, use a crush proof box with seams sealed completely with tape; Be sure to include the sample submission form required by your state.
75 Delivering a sample Contact the Plant Clinic (217-333-0519). 75Delivering a sampleContact the Plant Clinic ( ).Samples must be fresh and in good condition. Enclose in plastic as if mailing. Label the bags.Rapid delivery is critical (no Friday shipments).Slide 72.If you have gone through the DDDI system and have been told to take a sample to the Plant Clinic, you may mail or hand deliver your sample. If you are delivering a sample, contact the Plant Clinic ahead of time. Rapid delivery and cool temperatures are critical so that the sample will arrive in good condition. Ship for a weekday arrival so that your sample does not sit in unfavorable conditions over the weekend. Whether you mail or hand deliver the sample, it is still required that the sample be placed in zippable bags to prevent spread of the fungus.
76 76Sampling remindersThe accuracy of a disease diagnosis can only be as good as the sample and information provided.Sample must be representative of symptoms and severity in the field and must contain the right material.Slide 76.Remember, the accuracy of a disease diagnosis can only be as good as the sample and information provided. Sample must be representative of symptoms in the field and must contain the right material.
77 Sampling reminders Sanitation Chain of custody disposal of material 77Sampling remindersSanitationdisposal of materialcontainment while shippingclean toolsChain of custodyrestrict access to samplemake sure sample collection location is retraceableSlide 77.Sanitation and chain of custody of a regulated pest are very serious matters. If you are collecting a sample remember: APHIS approved disposal methods of the material includes double-bagging and disposal at a municipal landfill. APHIS approved containment while shipping includes double zippable bags in a crush-proof box with sealed seams. Be sure tools are cleaned – free of visible soil and plant material - and disinfected as well. You can use a solution of 10% household bleach for disinfecting tools. To ensure proper chain of custody, restrict access to the sample, and make sure the sample collection location is retraceable.
78 Diagnostics: laboratory tests 78Diagnostics: laboratory testsThere are three detection methods:Antibody test (ELISA)Plating on selective mediaDNA (PCR)Relatively expensiveTime consumingELISAPlatingPCRSlide 78.Once a sample reaches the lab, up to three diagnostic procedures will be performed on it: an ELISA antibody test, plating, and a DNA test through PCR. Each procedure is relatively expensive and time consuming. It is important that you only send in samples that are likely to be infected with P. ramorum. If too many samples are sent in, it will swamp our lab and regulatory personnel and they may have difficulty in addressing high priority samples. This is the reason we need to screen samples carefully.Photo: Natalie Goldberg, New Mexico State University
79 Where to go for more information 79Where to go for more informationAPHIS:California Oak Mortality Task Force:NC IPM:IL Home, Yard, & Garden Pest Newsletter:Slide 79. Bruce Paulsrud’s sectionNo doubt we will all learn more about P. ramorum in the weeks, months and years to come. I encourage you to refer to these websites and newsletters to stay current. You’ve heard about the USDA-APHIS website several times already; it is an excellent resource with national perspective. The California Oak Mortality Task Force website gives you the perspective from within battle zone, but remember that they are dealing with different climatic conditions and often different plant species. The NC IPM website provides a wealth of information and links. In addition, you’ll find the final IL P. ramorum Detection & Response Plan at the NC IPM website. Watch the Illinois Home, Yard, & Garden Pest Newsletter for the latest P. ramorum news and advise as it pertains to Illinois.
80 Acknowledgments Revising authors Monica David Nancy Pataky 80AcknowledgmentsRevising authorsMonica DavidNancy PatakyBruce PaulsrudOriginal authorsJennifer ParkeSusan FrankelJanice AlexanderCarla ThomasSlide 80.This presentation was originally developed in October 2004 by Jennifer Parke, Susan Frankel, Janice Alexander, and Carla Thomas. It was updated and tailored for Illinois by Monica David, Nancy Pataky, and Bruce Paulsrud.A special thank you to the Illinois Sudden Oak Death Task Force Members for developing the IL P. ramorum Detection & Response Plan:Dave Bender - Illinois Nurserymen’s AssociationMark Cinnamon - Illinois Department of AgricultureMonica David, Nancy Pataky, Bruce Paulsrud, and Dave Shiley - University of Illinois ExtensionKarel Jacobs and Edith Makra - The Morton ArboretumSteve Knight – USDA Plant Protection QuarantineDick Little - Illinois Forestry Development CouncilTom Wilson - Illinois Dept. of Natural ResourcesThank you very much for your attention. We will now move to the question and answer portion of the presentation and then Phil Nixon will provide us with updates regarding several invasive insects. Monica David, Nancy Pataky, and Bruce Paulsrud will be happy to try to answer any questions you may have.Illinois Sudden Oak Death Task Force MembersDave Bender, Mark Cinnamon, Monica David, Nancy Pataky, Bruce Paulsrud, Dave Shiley, Karel Jacobs, Edith Makra, Steve Knight, Dick Little, and Tom Wilson