HomeMy WebLinkAboutFAQ-EAB-FEB 9 2016Prepared by Mark Shour, Laura Jesse, and Donald Lewis, Iowa State University Extension and Outreach – Page 1
February 9, 2016
Frequently Asked Questions/Answers on Emerald Ash Borer (EAB)
1. What is the emerald ash borer? It is a very small, shiny green beetle (½ inch long x ⅛ inch
wide; about the size of Mr. Lincoln’s image on a penny).
2. What does EAB eat? Hosts are species (and cultivars) of ash in the genus Fraxinus. Hosts include
green ash (e.g., ‘Marshall Seedless’, ‘Patmore’, and ‘Summit’), white ash (e.g., Autumn Purple®)
black ash, blue ash, and pumpkin ash. Manchurian and Chinese ash trees are primary hosts in its
homeland [Eurasia]. A new host record of white fringetree (Chionanthus virginicus) was discovered
in Ohio; this is not a common plant in Iowa. Mountain ashes (Sorbus species) are NOT hosts.
3. Where is EAB from? This beetle is native to Asia and is found in China and Korea. It also has been
reported in Japan, Mongolia, the Russian Far East, and Taiwan. EAB arrived in the United States
sometime before 2002 in wood packing materials. It has been recorded feeding on F. chinensis and F.
mandshurica as a native borer.
4. How did it get to Iowa? Most EAB infestations in the United States have been started by people
unknowingly moving infested firewood, nursery plants, or sawmill logs. The adult beetle also can fly
short distances (2 to 5 miles).
5. Should I be concerned about EAB? Yes. It kills ash trees, usually in 2-4 years. In the Midwest,
millions of ash trees have been killed by EAB since 2002. There are about 3.1 million urban ash trees
and an estimated 52 million ash trees in forests in the state of Iowa. Statewide, Iowa averages 16-
17% ash on city property, though the ash component in tree inventories can reach 87%.
6. How do I know if I have an ash tree in my yard? Two sources to check on tree identification are:
https://store.extension.iastate.edu/ItemDetail.aspx?ProductID=1482 and
http://www.extension.iastate.edu/forestry/iowa_trees/tree_id.html
7. How do I know if my ash tree is infested? Look for the following symptoms:
https://store.extension.iastate.edu/Product/EAB-or-Native-Borer and
https://store.extension.iastate.edu/Product/Common-Problems-of-Ash-Trees
a. Canopy thinning or dying branches in the top of the tree
b. Water sprouts (suckers) halfway up the trunk
c. Feeding notches on edge of leaflets
d. Woodpecker feeding sites/many bark flakes on lawn
e. S-shaped feeding galleries under dead bark
f. D-shaped exit holes (1/8 inch diameter)
8. F o r c o u n t i e s n o t y e t k n o w n t o b e i n f e s t e d w i t h E A B , w ho can help me determine
if my tree is infested? Contact one of the following if you suspect EAB in your tree:
a. State Entomologist Office, IDALS: 515-725-1465
b. Iowa DNR Forestry: 515-725-8453
c. ISU Extension and Outreach: 515-294-1101
9. Who should be thinking about treating ash trees? If you are a homeowner within 15 miles of a
known infested area, you can consider treatment of a healthy ash tree during the growing season (see
#10 below). If you are not in a known infested area, treatment may be premature.
10. Ash Borer Management Options www.extension.iastate.edu/Publications/PM2084.pdf
a. Ash trees can be protected with insecticide applied by a commercial pesticide applicator or
the homeowner. Trees must be healthy, vigorously growing, and valuable to your landscape.
b. Most of the treatments (i.e., imidacloprid and dinotefuran) must be done each year for
the life of the tree. Two active ingredients will last for two years in a light EAB
Prepared by Mark Shour, Laura Jesse, and Donald Lewis, Iowa State University Extension and Outreach – Page 2
February 9, 2016
infestation: emamectin benzoate and azadirachtin. In heavy EAB infestations, only
emamectin benzoate is effective for two years; azadirachtin must be injected every
year.
c. Keep in mind that treatment may not be effective for a given tree due to past injuries, age of
the tree, soil moisture, soil compaction, and other site and environmental factors.
d. Preventive treatments are most effective. Infested trees with less than 30% dieback of the
crown might be saved for a few years, but the tree’s crown will be misshaped as a result
of removing the dead branches.
e. Ash trees within 15 miles of a confirmed EAB site are at risk of EAB attack. Preventive
treatments are suggested within this risk zone, but may be premature outside this area.
Continued monitoring of ash trees outside the risk zone for EAB symptoms is suggested.
f. Systemic insecticides require time, good soil moisture, and active tree growth for distribution in
the ash tree. Most soil-applied products (soil drench, granular, soil injection) must be
applied in early spring (mid-April to mid-May) to be effective. Basal trunk sprays using
dinotefuran can be applied until mid-June and are most effective for trees <18”dbh.
Trunk injections can generally be made during full canopy (April through August),
provided there is good soil moisture.
g. Soil drench homeowner treatments are effective for ash trees up to 60 inches in circumference
(20 inches diameter), while granular treatments are recommended for trees up to 36 inches
in circumference (12 inches diameter). Homeowners can make only one application per year.
Trees larger than 60 inches in circumference (20 inch diameter) will need to be treated by a
certified commercial pesticide applicator.
h. There are several treatment options available for ash trees when a commercial pesticide
applicator makes the application. Always use a certified applicator with experience in
treating trees. For assistance in making a list of prospective certified applicators in your
county/area, go to: http://store.extension.iastate.edu/Product/Finding-a-Certified-
Pesticide-Applicator-for-Emerald-Ash-Borer-
i. There is a per acre use limitation for soil treatments and basal bark treatments; consult the
product label when planning applications. There is no per acre use limitation for trunk
injections.
j. ISU Extension and Outreach does NOT recommend canopy sprays because of limited
effectiveness, the need for specialized equipment, spray drift, and possible adverse effects to
nontarget organisms.
11. If I am contacted by a pesticide applicator to treat ash trees for EAB in the fall or winter, what
course should I take? The best time for most preventive applications for EAB is spring; some
products can be used throughout the summer and early fall (before leaf color starts to change). IF you
live within 15 miles of a confirmed EAB infested site, get an estimate for the treatment. It is best to get
at least one additional estimate before any work is done. IF you live outside the risk zone, thank the
applicator for showing interest and keep the company information on file.
12. Where has EAB been found in Iowa? EAB infestations have been confirmed in thirty Iowa
counties. Counties considered infested:
a. Allamakee –New Albin, Lansing, Black Hawk Point, Plough Slough (2010)
b. Appanoose – Moravia (2014)
c. Black Hawk–Waterloo (2014)
d. Boone – Boone (2014)
e. Bremer–Waverly (2014)
f. Cedar – Mechanicsville (2013)
g. Clinton – Clinton (2015)
h. Dallas – Waukee (2015)
i. Davis – Rural area north of Bloomfield (2015)
j. Des Moines – Burlington (2013)
k. Dubuque – Dubuque (2015)
l. Henry – Mt. Pleasant (2014)
m. Jasper – Newton (2014)
Prepared by Mark Shour, Laura Jesse, and Donald Lewis, Iowa State University Extension and Outreach – Page 3
February 9, 2016
n. Jefferson – Fairfield (2013)
o. Johnson – Iowa City (2016)
p. Keokuk – Hedrick (2015)
q. Lee – Fort Madison (2015)
r. Linn – Cedar Rapids (2015)
s. Lucas – Private woodlot (2014)
t. Mahaska – Eddyville (2014); rural area NW of Oskaloosa (2015)
u. Marion – Maryville (2014)
v. Monroe – Private property (2014)
w. Montgomery – Rural area NW of Red Oak (2015)
x. Muscatine – Muscatine (2014)
y. Polk – Urbandale, West Des Moines (2015); Des Moines, Windsor Heights (2016)
z. Poweshiek – Grinnell (2015)
aa. Scott – Davenport (2015)
bb. Story – Story City (2014)
cc. Union – Creston (2013)
dd. Wapello – Eddyville (2014)
13. Now that EAB has come to Iowa, is there some plan to manage/contain this pest? A
detailed plan has been developed by Iowa’s collaborative agencies. The EAB Response Plan
and other current Iowa information about EAB are given at:
http://www.extension.iastate.edu/psep/EmeraldAshBorer.html
14. What does an EAB quarantine mean? A quarantine by state and U.S. agriculture departments
means that hardwood firewood, ash logs, and wood chips cannot be moved out of the area without a
permit. Homeowners must not remove their ash tree or firewood from their tree to an area outside the
quarantine. Tree removal companies must not haul logs or firewood outside the quarantine area
unless inspected and treated as required by the regulations.
15. How many counties in Iowa have been quarantined? The entire state (99 counties) of Iowa has
been quarantined for EAB.
16. What should a homeowner or tree care company do with ash trees cut down in or near the
infested area? We request that you dispose or use the wood within your county.
17. Can I use the mulch produced by chipping an EAB infested tree for landscaping? If the
chip size is 1 inch x 1 inch or smaller (in two dimensions), recent research has shown that EAB
does not survive and the chips can be used without concern. If the chip size is larger, however,
it is best to bury or burn these chips (according to local ordinance) as soon as practical to
prevent spreading EAB into new areas.
18. Can I use the wood from an EAB infested ash as firewood? Yes, with one qualification.
Once the ash tree is cut into pieces, the pieces can be used as firewood on your property. Please
do not take infested firewood with you on camping trips, tailgating, hunting, or other places
because you will spread EAB.
19. What can my ash tree be used for, besides firewood? Depending on the straightness of the
trunk and main branches, ash killed by EAB can be processed for lumber or can be debarked
and used for outdoor furniture or landscaping. Pieces of scrap wood with the bark still attached
should be burned, buried, or chipped.
20. What general recommendations are available to communities? The Iowa Department of Natural
Resources – Forestry Bureau has worked with several communities to deal with EAB infestations.
Contact Tivon Feeley (515-725-8453) or Emma Hanigan (515-725-8201) for more information.
Prepared by Mark Shour, Laura Jesse, and Donald Lewis, Iowa State University Extension and Outreach – Page 4
February 9, 2016
21. Where can I find current information about EAB on the Internet? Sites to gather current
information about this exotic pest include:
a. National: www.emeraldashborer.info
b. ISU Extension & Outreach: http://www.extension.iastate.edu/psep/EmeraldAshBorer.html
c. IDALS: www.IowaTreePests.com
d. IDNR: www.iowadnr.gov/Environment/Forestry/ForestHealth/EmeraldAshBorer.aspx
22. Who is a local contact? Call your county Iowa State University Extension & Outreach office for
more information: Johnson County – 319-3372145. If you live in another Iowa county and would
like to contact your Extension & Outreach office, visit the following site and click on your county;
the phone number is in the blue box in the upper right corner of each county’s web page:
http://www.extension.iastate.edu/content/county-offices