Top 10 Problematic Trees of Illinois in 2013

Based on Plant Clinic sample submissions and questions, the following trees were considered to be the most problematic in 2013:

*The chart above does not include nematode sample data

(Links below provide further information on disease, insect, as well as abiotic threats discovered on each tree in 2013.)


#10. Crabapple
 Cedar apple rust:  http://hyg.ipm.illinois.edu/article.php?id=482
 Apple scab:  http://urbanext.illinois.edu/focus/applescab.cfm

#9.  Juniper
 Phytophthora Alert:  http://universityofillinoisplantclinic.blogspot.com/2013/06/phytophthora-root-and-crown-rot-alert.html

#8.   Arborvitae (Cedar)
Phytophthora Alert:  http://universityofillinoisplantclinic.blogspot.com/2013/06/phytophthora-root-and-crown-rot-alert.html

Browning of Evergreens:  http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4144
Conifer Dieback:  http://www.ppdl.purdue.edu/ppdl/pubs/briefs/conifer-dieback.pdf

#7.  Ash (excluding Emerald Ash Borer issues)
EAB:   http://hyg.ipm.illinois.edu/article.php?id=464
Ash Anthracnose:   http://hyg.ipm.illinois.edu/article.php?id=470

#6.  Ornamental Pear
Pear blights:  http://hyg.ipm.illinois.edu/article.php?id=490

#5.  Elm 
Verticillium wilt:  http://hyg.ipm.illinois.edu/article.php?id=518

#4. Pine
Eastern White pine + Drought = Problems
http://universityofillinoisplantclinic.blogspot.com/2013/03/eastern-white-pinte-drought-problems.html

#3.  Maple
Maple leaf blights:  http://hyg.ipm.illinois.edu/article.php?id=473
Taphrina diseases:  http://hyg.ipm.illinois.edu/article.php?id=478
Maple early fall color:  http://www.dnr.state.mn.us/fid/august97/08259704.html

#2.  Spruce
U of I Plant Clinic Report on Spruce Problems:  http://web.extension.illinois.edu/plantclinic/downloads/Plant%20Clinic%20Report%20Spruce.pdf

and the number one problematic tree of 2013:

#1.  Oak
Taphrina diseases:  http://hyg.ipm.illinois.edu/article.php?id=478
Oak wilt:  http://hyg.ipm.illinois.edu/article.php?id=506
Bacterial leaf scorch (BLS):  http://hyg.ipm.illinois.edu/article.php?id=513
Bur Oak Blight (BOB):  http://hyg.ipm.illinois.edu/article.php?id=537
NEW U of I Plant Clinic Report on Oak Problems:  http://web.extension.illinois.edu/plantclinic/downloads/Plant%20Clinic%20Report%20Oak%20LO.pdf