Emerald Ash Borer - Illinois First Detector Tree Pest Program

 

 The Emerald Ash Borer (Agrilus planipennis), or EAB, has been gradually making its way across the continental US since 2002. This beetle has killed millions of ash trees to date and poses a threat to all communities where ash grows. Originating from Asia, these small, green jewel beetles pose a serious threat to ash trees across the states. EAB has been reported in Canada as well as Michigan, Illinois, Indiana, Iowa, Kentucky, Maryland, Minnesota, Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin. The EAB has a 1-2 year lifecycle. Adult females lay eggs on the tree and within 1-2 weeks the larvae emerge and bore through the bark and into the cambium. This is the nutrient-rich area just under the bark. Larvae feed laterally around the tree, girdling it and preventing nutrients from travelling up through the tree. Signs of infestation start with thinning of the upper canopy. Up to half of the canopy may be destroyed after a few years of infestation and the tree may be killed after about six years. Epicormic shoots will appear in the branch collars of the tree and around the base. EAB prefer to attack stressed or damaged trees, but will also infest healthy trees. Due to the severity of the problem, much is being done to prevent the spread of EAB. There are many public ad campaigns discouraging people from moving wood out of the county of its origin to reduce the spread of this and other borers. Federal and State agencies as well as Universities are working with the public to prevent the spread of the Emerald Ash Borer.
 (Rachel Kirchoefer and Phil Nixon)

Early detection and response is key to managing invasive pests. The Illinois First Detector Workshops are aimed at improving first-detector training and invasive species awareness. Plan to attend these workshops focusing on current and emerging invasive forest pests in Illinois. Each location will have sessions devoted to the emerald ash borer, thousand cankers disease, and invasive plants. In-depth training sessions will highlight identification, symptoms, management, and much more!

Registration for this program will be handled by various University of Illinois Extension host sites.  You can easily register via the Extension links and contacts listed below. 

February 12 – Springfield, IL –Springfield Extension Office

Hosted by University of Illinois Extension Logan-Menard-Sangamon Unit

Register at: https://webs.extension.uiuc.edu/registration/?RegistrationID=7542

(Registration will be open until February 5^th.)

Contact:  Jennifer Fishburn- fishburn@illinois.edu

February 26 – Moline, IL -Deere-Wiman Carriage House

Hosted by University of Illinois Extension Henry-Mercer-Rock Island-Stark Unit

Register at: https://webs.extension.uiuc.edu/registration/?RegistrationID=7407

(Registration will be open until February 26^th.)

Contact:  Martha Smith -smithma@illinois.edu or Tracy Mulliken- tmully@illinois.edu

March 7 – Mt. Vernon, IL –Jefferson County Extension Office

Hosted by University of Illinois Extension Bond-Clinton-Jefferson-Marion-Washington Unit

Register at: www.extension.uiuc.edu/bcjmw

(Registration will be open January 22nd until February 28^th.)

Contact:  Chelsie Keene- ckeene@illinois.edu

March 14 – Collinsville, IL – Collinsville Extension office

Hosted by University of Illinois Extension Madison-Monroe-St. Clair Unit

Register at: http://web.extension.illinois.edu/mms/

(Registration will be open January 7th until March 8th and cash, check, and charge accepted.)

Contact:  Sarah Ruth- ruth1@illinois.edu

March 21 – Champaign, IL – Champaign Extension Office

Hosted by University of Illinois Extension Champaign-Ford-Iroquois-Vermilion Unit

Register at: http://web.extension.illinois.edu/cfiv/

(Registration due by March 18th. No refunds after March 20^th.)

Contact:  Sandy Mason- slmason@illinois.edu

March 26 – Lemont, IL- Midwest Golf House (*FULL)

Hosted by University of Illinois Extension Cook County

Register at: http://extension.illinois.edu/go/treepest

(Registration will be open December 1st until March 17th.)

Contact:  Greg Stack -gstack@illinois.edu

April 4 – Lemont, IL- Midwest Golf House

Hosted by University of Illinois Extension Cook County

Register at: http://extension.illinois.edu/go/treepest

(Registration will be open until March 26th.)

Contact:  Greg Stack -gstack@illinois.edu

A $25 registration fee covers on-site lunch and training materials. No registration at the door. If you do not cancel prior to the workshop, and do not attend, there is no refund.

All workshops 9:00 AM - 3:00 PM

*Each Workshop is worth

4.0 Continuing Forestry Education Credits

4.25 Continuing Education Credits (CEU’s) for IAA Certified Arborists

Questions:  Contact Stephanie Porter at satterle@illinois.edu

Honeylocust knot or galls - Call for more research

Question: "I was wondering if you know of any treatment for Honey Locust Knot? Or what is your suggestion to deal with that problem. I have a client that has 7 Honey Locust tree's that are clearly infected with this Knot" -Arborist from Maryland

Picture of a honeylocust sample received at the U of I Plant Clinic with galls on branches.

Picture of a honeylocust sample received at the U of I Plant Clinic with galls on branches.

You recently emailed Nancy Pataky with a question about honeylocust knot.  She is now retired and she has forwarded your email to me.  Honeylocust knot can be tricky, as to my knowledge, the cause has not been proven by research.  In my recent investigation on this topic, I have found that there could be many different causes for “knots or galls” in honeylocust.  You first need to rule out chemical/herbicide use near these trees.  For example, the herbicide, Imprelis (no longer sold), has been found by Midwest plant diagnosticians to cause knots in honeylocust.  Insects and bacteria are also some other causes for honeylocust galls.

We rarely see these honeylocust galls in Illinois, but when we did, we did not find any evidence of chemical or insects in the galls; therefore, Nancy Pataky suspected a bacterial cause.  She wrote about this topic in the U of I Home, Yard, and Garden newsletter:  http://hyg.ipm.illinois.edu/pastpest/200805a.html . Nancy Pataky’s theory of bacterial (Pseudomonas savastanoi) formed galls was based on research from the Ohio State:  http://ohioline.osu.edu/sc189/sc189_55.html . If you read this bulletin from the Ohio State, they had reports of this disease mainly in the Midwest, but also in Maryland.  The spread of the bacterium was thought to be caused by the lack of sanitation during hand pruning and the trees eventually died.  In this newsletter article, Nancy Pataky mentions that a plant pathology student at the Ohio State was beginning a new project on this problem; however, we have since learned that the funding was lost. 

We have an Agdia plant diagnostic listserve, a great resource for plant diagnosticians across the US to discuss problem plant samples. Here are some recent posts about honeylocust galls:

“Several years ago (2003ish) while working in Maryland, we found galls on honeylocust.  I'm surprised that this link is still active, but you can look at some images:  http://www.mda.state.md.us/sc/plants-pests/plant_protection_weed_mgmt/new_pest_detections_md_nurseries_-s2.php .  We called it honeylocust gall or knot.  The problem was on Shademaster and Skyline honeylocust and we found it both in the landscape and at a nursery.  It was present on the landscape trees for multiple years and eventually killed many of the trees.  At that time, I did some research and there was an article on the internet that suggested that Pseudomonas savastanoi was the cause.  I sent samples to Ohio State.  I do not know if they ever confirmed if this was the cause or what the status of the research is at this time.”

Another plant diagnostician that had a honeylocust sample with galls reported the following on the diagnostic listserve: “We had a similar case and could not rule out gall midge.  An entomologist thought it might be Neolasioptera brevis, but we had no direct evidence.” 

Since the release of Nancy Pataky’s article, I have received inquiries and reports about galls on honeylocust.  For example, a Canadian plant diagnostician has reported, “We had one honey locust sample came in the middle of July showing exactly the same gall symptoms. After one month's moist chamber incubation, some Lepidopteran larvae (Family Pyralidae,snout moths) came out from the galls. I have seen reports on locust twig borer (Ecdytolopha insiticiana) but our entomologist insisted that what we got were not the same.”

Therefore, if we are not sure of the cause, we can’t be sure of a treatment.  I would suggest that you send a sample to your local Plant Clinic.

I would also suggest that you rule out chemical/herbicide issues.  Next, I would try to cut into a gall and check for signs of insects.  If you suspect that this is a bacterial induced gall problem, please be sure to sanitize your pruners after each cut.   I am sorry, but, unfortunately, I have no other management suggestions besides keeping the tree in good health by fertilization and watering during times of drought.   

Please let me know if you know of any recent research done on honeylocust knot or gall. 

Stephanie Porter

Illinois Can Learn More about Thousand Cankers Disease of Walnut at First Detector Trainings

Thousand Cankers Disease, or TCD is a new, serious disease complex in the U.S. that affects certain walnut species (Juglans spp.).  This disease was identified and named in 2008 in the Western U.S., but recently has been found in the Eastern U.S.  TCD has most recently been discovered in areas of Tennessee (August 2010), Pennsylvania (June 2011), and Virginia (August 2011).   Thousand Cankers Disease, caused by the fungal pathogen, Geosmithia morbida, has been found to be associated with the only known insect vector, the walnut twig beetle (WTB, Pityophthorus juglandis Blackman).  The infection and colonization of the fungus Geosmithia morbida around walnut twig beetle galleries just beneath the bark causes many dead pockets or cankers in the phloem, just as the name “Thousand Cankers” states.  The cankers begin decaying the wood at multiple walnut twig beetle entry and exit points on branches larger than ¼ inch, and along trunks.  These cankers can kill the cambium and discolor the sapwood; thus causing twig or branch girdling, and eventually tree death. Because Thousand Cankers Disease has been associated with sudden walnut mortality in the United States, this disease is considered an economic and environmental threat.  Therefore, public awareness, education, and effective regulations for this disease are very important to prevent the spread of Thousand Cankers Disease to other native walnut areas in the U.S.

University of Illinois Extension announced that a first-detector training program focusing on tree pests will be offered at six locations in Illinois in February and March 2013. These courses will provide in-depth training on current and emerging pathogens and insects affecting Illinois trees.

The target audience includes certified arborists, tree care professionals, master gardeners, master naturalists, forestry and natural resource professionals, conservationists, and others with an interest in trees. Continuing Education Units (CEUs) will be available.
The objectives of the training include the following:

• Improve first-detector training and invasive species awareness,
• Reduce potential risks from pathogens and pests,
• Increase rapid and affordable plant diagnostic support to local, state, and national agriculture and green industry programs and to end-users.

The 2013 program will focus on Emerald Ash Borer (EAB), thousand cankers disease (TCD), and invasive plant species. Subjects to be covered in the course include:

• Identification/detection,
• Life cycle/biology,
• Hosts,
• Sampling,
• Management,
• Commonly confused look-alikes,
• Regulation

This Illinois First-Detector Tree-Pest Training Program will be held at the following locations:

• Springfield, U of I Extension conference room, Feb. 12, 9 a.m. to 3 p.m.
• Quad Cities, Deere-Wiman Carriage House, Feb. 26, 9 a.m. to 3 p.m.
• Mt. Vernon, U of I Extension conference room, March 7, 9 a.m. to 3 p.m.
• Collinsville, U of I Extension conference room, March 14, 9 a.m. to 3 p.m.
• Champaign, U of I Extension conference room, March 21, 9 a.m. to 3 p.m.
• Lemont, University of Illinois Extension, Midwest Golf House Complex, March 26, 9 a.m. to 3 p.m.

Registration is $25; lunch will be provided. This fee will help cover the program costs as well as provide funding to continue this program on an annual basis. Registration is not open at this time but will be held at the host U of I Extension office.

Each participant will receive a binder of EAB, TCD, and invasive plant information. A special feature will be key tree drawings (provided by Jean Burridge) to aid in identifying ash, walnut, or “look-alike” trees. Additional online training modules covering topics that will not be discussed during the one day program will be available to program participants prior to training.

All participants will receive a certificate stating that they are Illinois First Detectors.
This program is made possible by an Illinois IPM Grant and was developed by a special committee: Stephanie Porter, U of I plant clinic diagnostician and outreach coordinator, Kelly Estes, U of I agricultural pest survey coordinator, Travis Cleveland, U of I extension specialist in the Pesticide Safety Education Program (PSEP), Jay Hayek, U of I extension specialist in forestry, David Shiley, U of I extension educator, Andi Dierich, Morton Arboretum Forest Pest Outreach and Survey Project, Emily Hanson, Sothern Illinois University urban and community forester, and Jean Burridge, U of I Plant Clinic staff and certified arborist.