Prepared by Forest, Mineral & Fire Management Division

Forests comprise 53% of the land area of the state, or about 19.3 million acres. These

forests are a critical component of Michigan’s environment and economy for the

recreational opportunities and the products they provide. Forestry related industries and 

manufacturing employ 150,000 people statewide and annually contribute $9 billion to

the state’s economy. Additionally, forest-based tourism and recreation support 50,000

jobs and add $3 billion to Michigan’s economy. Michigan’s forests contribute to clean 

air, water, and reduce soil erosion. 

The Emerald Ash Borer quarantine has been extended to 20 quarantined counties in the 

southeast corner of Michigan’s Lower Peninsula (LP). Nineteen other counties have

quarantined townships buffering EAB eradication sites. Five other LP counties where EAB 

life stages were detected in firewood only are being monitored. In summary, EAB has

been detected in 44 of 68 LP counties including the three northern most counties. The 

Northern Lower Peninsula (NLP) detections are the result of a two trap tree per township 

trap tree survey by the Michigan Department of Agriculture. This equates to one trap

tree for every 18 square miles or 11,520 acres, or a survey of 5% of the forest resource

assuming each tree draws beetles within 1⁄2 mile. Plans for a higher density NLP survey in 

2005 will provide a better picture of EAB distribution.

 

State and federal agencies continue to battle this exotic threat to our ash resources. 

Plans for 2005 include a repeat of a cooperative US Forest Service, Michigan

Technological University, and Michigan DNR statewide detection survey. In 2004 Trap

trees were deployed in 116 high risk state and federal parks and campgrounds

throughout the state to detect new EAB populations introduced through the movement 

0

5

10

15

20

25

30

% of Total

Maple-Birch

Aspen-Birch

Elm-Ash-Soft-Maple

Oak-Hickory

Red and White Pine

Northern W hite-Cedar

Jack Pine

Black Spruce

Balsam Fir-White Spruce

Tamarack

Eastern Redcedar

Major Forest Types

Of Michigan
Prepared by Forest, Mineral & Fire Management Division 

2 

of firewood. Risk was defined using maps of the state’s ash resources and State Park 

databases showing park visits from residents of EAB infested counties. The survey effort 

included visual inspections of firewood and ash trees in these and adjacent areas. EAB 

was detected in firewood in three new counties. 

The Michigan Department of Agriculture covered the state with a net of 10,000 trap trees 

in 2004. With most trap trees peeled to check for larvae, 137 trees were positive for EAB. 

Fifty-eight of these trees had only larvae, with no adults in the sticky bands. Without trap 

trees to attract adult EAB and peeling of trees to detect larvae, these sites would not 

have been detected. 

The regulatory removal of ash on state and 

national forest lands to eradicate or contain EAB 

outlier populations (e.g. populations detected 

outside of quarantined areas) is currently being 

discussed. Topics of discussion include: harvest 

strategies; utilization opportunities versus disposal 

costs of wood products; meeting best 

management practice standards; working in 

natural areas, wilderness areas, old growth areas, 

and /natural scenic river corridors; protecting the 

residual forest resource. 

The Forest, Mineral & Fire Management Division of 

the Michigan DNR conducted a firewood sweep 

in December, 2004 to remove all hardwood 

firewood left at State Forest Campgrounds. 

Collected wood was burned to prevent the 

possible emergence of EAB adults in the spring. 

Beginning In 2005 ash firewood is banned from 

state lands, parks and campgrounds. 

The Division is also developing ash management guidelines for use on state lands. 

Challenges include determining the long-term management goals in areas where ash 

regeneration is poor or non-existent. 

The U.S. Forest Service Forest Health Technology Enterprise Team, Fort Collins, CO in 

cooperation with the Michigan DNR, MDA & APHIS PPQ is evaluating the placement of a 

Reduce Ash Zone (RAZ) to stop the natural spread of EAB. The placement of this zone 

requires good information on current areas of infestation and the number and size of ash 

trees to be removed over time. Removals would primarily be non-regulatory. Incentives 

calling for the conversion of ash resources to other tree species would be offered to 

manage urban trees, woodlots and forest lands. 

Regulating the movement of firewood by the general public from infested areas remains 

the most difficult of tasks. Much is being done to get the message out: 

DON’T MOVE FIREWOOD!

Visit the following websites for updates on EAB management, surveys and research: 

US Forest Service: http://www.na.fs.fed.us/spfo/eab/mgmt/mgmt.htm 
3 

MI http://www.michigan.gov/mda 

Michigan State University EAB Site (Homeowner info): http://www.emeraldashborer.info 

Michigan Technological University EAB Site (Survey): http://www.emeraldashborer.org 

was common in many parts of the state. 

to past drought conditions. Trees growing in wet soils, such as black ash, often suffer 

with a prolonged drop in soil moisture. Rising water tables after a prolonged drought 

may also drown deeper roots developed as the tree sought moisture during the drought 

years. 

is causing extensive wind throw of mature ash in high 

quality northern hardwood stands in Northern Lower Michigan. Affected stands appear 

140 ft2). Stresses from overstocking may be involved. 

condition has since been reported in Ontario and Wisconsin. 

A Hemlock Woolly Adelgid

from infested counties of other states. All eastern 

hemlock shipments require a 

certificate. This follows the interception of the insect 

at two Michigan nurseries in 2000. 

Hemlock woolly adelgid, which is dispersed by wind 

and by movement of infested firewood, feeds on tree 

sap, killing needles, twigs and branches. 

eventually die: 

http://www.fs.fed.us/na/morgantown/fhp/palerts/hemlock/hemlock.htm 

This is part of a Forest 

No hemlock woolly 

type. This represents 138 million beech in all size classes. Of these, 15 million larger beech 

Several 

thousand acres of beech forests have been salvaged in forests and recreation areas in 

the eastern Upper Peninsula. 

Beech Bark 

Disease Resistance. 

individuals. 

Prepared by Forest, Mineral & Fire Management Division 

 Department of Agriculture EAB Site (Quarantine): 

Black Ash Decline and Mortality This is related 

during droughts. Wetland trees tend to develop shallow root systems that cannot cope 

An unidentified White Ash Root Rot 

to carry high basal areas (> This 

 quarantine continues to 

restrict movement of eastern hemlock into Michigan 

phytosanitary 

Infested tree 

Rapid early detection surveys for the adelgid were conducted statewide for the third 

straight year in hemlock stands and in areas adjacent to nurseries. 

Health Monitoring Evaluation Monitoring project funded in 2002. 

adelgids were found in 2004. 

Beech Bark Disease (BBD) threatens Michigan’s 7.2 million acres of Maple-Beech-Birch 

(greater than 9-inch diameter) are highly vulnerable to damage. BBD is presently killing 

beech trees in areas infested with beech scale for 10 years or more (Figure 1). 

The USDA Forest Service Research Facility in Delaware, Ohio is using trees from Ludington 

State Park, Ludington, Michigan and Michigan’s Upper Peninsula to study 

Crosses between the resistant and susceptible tree produced 23% 

resistant individuals while crosses between two resistant parents produced 44% resistant 

Preliminary data provide the first genetic evidence that resistance is a 
2001 advancing front

2001 killing front

2003 advancing front

2003 killing front

FIA beech distribution

Prepared by Forest, Mineral & Fire Management Division 

4 

Map courtesy of Frank Krist, MDNR 

2001 advancing front 

2001 killing front 

2003 advancing front 

2003 killing front 

FIA beech distribution 

2001 advancing front

2001 killing front

2003 advancing front

2003 killing front

FIA beech distribution

Map courtesy of Frank Krist, MDNR

heritable trait. The ratios of resistant to susceptible individuals do not fit the ratio 

expected for a single gene trait, indicating that two or more genes may be involved. 

In the western Lower Peninsula, 

where beech bark disease was first 

discovered in 2000 in Ludington 

State Park, the spread of the 

disease is slower than in the Upper 

Peninsula, due to the fragmented 

nature of the forests in the region, 

which has reduced the number of 

beech trees on the landscape. 

In addition, spot infestations of 

beech scale have been detected 

in Emmet County at the tip of the 

Lower Peninsula, and on the west 

end of Bois Blanc Island near the 

Mackinaw Bridge. 

Michigan State University began a study in 2004 called Current and Projected Spread of 

Beech Bark Disease in Michigan. Their goal is to develop a model based on empirical 

data to predict how rapidly beech scale and beech bark disease will spread through 

Michigan and to determine if spread rates in Michigan are consistent with estimates from 

other regions of North America. 
5 

Beech Bark Disease Monitoring & 

Impact Analysis System . 

• Beech scale abundance is affected by tree age, diameter, bark texture, bark 

chemicals, temperature fluctuations and genetics. 

• Spatial pattern of beech within and between stands, wind and animals affect rate 

• In addition to affecting tree crown condition, infected trees have reduced radial 

wood growth. 

More information about beech bark disease in Michigan can be found under the Forest 

Health section at: 

Incidence of the vascular disease oak wilt

To slow the overland spread of oak wilt, harvesting 

restrictions are being observed on state land. 

Harvesting activities in forests where red oak trees are 

responsible for spreading oak wilt 

and transmit them to oak trees that have been 

A total 78 epicenters were 

detected and treated. 

Menominee and Dickinson counties. 

remove threat of overland disease spread and to 

http://www.extension.bpp.msu.edu/oakwilt2.pdf 

Michigan State University and the Michigan Department of Natural Resources 

Sudden Oak 

Death (Phytophthora 

and State Departments of Agriculture to 

APHIS and the Michigan Department of Agriculture conducted the 

nursery surveys. 

Prepared by Forest, Mineral & Fire Management Division 

The University of Michigan continues to expand the

plot network Findings to date include: 

of development of beech scale populations and the rate of mortality 

http://www.forestry.msu.edu/msaf/ForestInfo/1-MainInfo.htm 

 continues to increase from 2003 levels in 

several areas around the Upper Peninsula and the northern Lower Peninsula of Michigan. 

being left cannot be cut between April 15 and July 15. 

Sap-feeding beetles

are most active during this time. These small (1/4-inch 

long) beetles can pick up spores from diseased trees 

damaged during logging operations. 

US Forest Service Oak Wilt Suppression funds were used 

to detect and treat oak wilt epicenters in Michigan’s 

Upper Peninsula in 2004.

Fifty-six thousand feet of rootgraft barrier were placed using a vibratory plow in 

Oak removals will 

occur within epicenters prior to the end of April, 2005 to 

protect in integrity of the root-graft barriers. 

For information about identifying and preventing oak wilt, visit: 

cooperated with the USDA Forest service to survey thirty nine oak sites for 

ramorum [SOD]). After SOD was confirmed in Monrovia Nursery (LA 

County, CA) in 2004, plants from the infected nurseries were traced to sites in Michigan. 

Michigan cooperated with a national initiative by the USDA Forest Service, APHIS-PPQ 

survey nurseries and the surrounding oak 

resources for SOD. 

No SOD was detected in Michigan nurseries or oak resources. 
6 

APHIS: 

Workshop for Midwest States 

St. Louis, MO 

Background 

Survey of Phytophthora Species

 Samples were sent to the USDA Forest Service Research Laboratory in St. Paul, 

Minnesota for processing. 

Eastern Larch Beetle, Dendroctonus simplex, 

Peninsula declined in 2003. This bark beetle 

became epidemic in tamarack (Larix laricina) 

repeated defoliation by the larch 

(Coleophora laricella). 

Areas of 

light budworm defoliation have been visible for the 

last few years. 

The Michigan Invasive Plant Council formally 

adopted an assessment system to categorize and 

The 

objectives of this assessment are: 1) To identify 

relevant biological, ecological, management and 

economic for evaluating potential 

the foundation 

recommended plans of action. 

Garlic Mustard (Alliaria petiolata) monitoring, 

management and eradication projects are gaining 

momentum in Northern Michigan. Public and 

keep garlic mustard from establishing in new areas of 

Upper Michigan. 

Prepared by Forest, Mineral & Fire Management Division 

2004 Exotic Forest Pest 

The Department of Natural Resources cooperated in a USDA Forest Service

 in Oak Forests of Michigan. Four declining and four nondeclining oak stands were selected in representative oak forest types in different areas of 

the state.

populations in Eastern and the South Central Upper 

stressed trees from the drought of 2000-2001 and 

casebearer 

Spruce Budworm was active in several counties in 

Michigan’s Upper and Lower Peninsulas. 

evaluate the invasive potential of plants. 

information 

impacts on Michigan ecosystems; and, 2) To provide 

of Michigan Invasive Plant Council 

private organizations are cooperating in efforts to 
7 

Ironwood, Michigan in the western portion of Michigan’s Upper Peninsula is the center of 

a Giant hogweed (Heracleum mantegazzianum) infestation. First discovered in 2001, 

To date 37 sites 

have been reported in Michigan. 

Forest Tent Caterpillar (FTC) (Malacosoma 

disstria Only scattered 

rainfall and cool weather. 

widespread Anthracnose of hardwoods and basswood thrips (Thrips calcaratus

damage due to prolonged feeding on immature leaf tissue. Although a wet 2004, oak 

and hardwood declines

Stresses from severely reduced starch reserves and resulting attacks by 

Agrilus bilineatus) contributed to declines 

on sites which were either too dry or too wet. 

The (Neodiprion lecontei

Dimlin 4L was 

This pesticide is an 

insect growth regulator, which prevents sawfly larvae from completing their 

development. 

For information about identifying and controlling redheaded pine sawfly, visit: 

http://www.na.fs.fed.us/spfo/pubs/fidls/pine_sawfly/pinesawfly.htm 

1990’s and culminated in 2001 when, for the first time 

in over a decade aerial surveys detected no 

defoliation in the state. Since then, egg mass 

numbers have been increasing steadily and 

A total of 

Peninsula. This is the first year that defoliation was 

extensive enough to be included on aerial sketch 

map surveys. Abundance of egg masses in this area 

growing population. 

Prepared by Forest, Mineral & Fire Management Division 

there are now approximately 20 known sites in the Upper Peninsula. 

Michigan is experiencing the end of a 4-5 year 

) epidemic. FTC defoliated 11.5 million acres in its peak year, 2001.

pockets of defoliation were detected in 2004. 

After two years of drought in 2002-2003, the spring and early summer of 2004 saw record 

This delayed tree growth and leaf development resulting in 

) leaf 

 from the previous year’s droughts were still evident where trees 

were off-site. 

secondary pests (e.g. two-lined chestnut borer, 

Red-Headed Pine Sawfly ) periodically defoliates young red and 

jack pines. Building sawfly populations were detected in many areas of the eastern 

Upper Peninsula in 2002 and in the northern Lower Peninsula in 2003. 

aerially applied to 333 acres of infested plantation red pine in 2004.

Gypsy moth (Lymantria dispar) populations continue 

on an upward trend statewide. This follows a long 

period of population decline that began in the early 

defoliation was locally heavy in some northern Lower 

Peninsula and Upper Peninsula counties.

45,244 acres were defoliated statewide in 2004, up 

from 38,119 acres in 2003. 

Gypsy moth defoliated 3098 acres of oak forests in 

southern Iron and Dickinson Counties in the Upper 

and in nearby Menominee County forecast a rapidly 
8 

The Jack pine budworm (

pest of jack pine. Stands older than 45 years that are growing on very sandy sites and 

Tree mortality 

Harvesting and other management activities can 

jack pine regeneration. 

most jack pine areas of the Upper Peninsula (UP) in 

2004. 

to heavily defoliated. Heavily defoliated areas in 

Most of these 

younger trees have viable buds on terminal 

branches, giving hope for survival in 2005. 

In the Lower Peninsula, jack pine budworm numbers 

declined slightly in 2004 following an upswing that 

began in 2001. 

have been recently defoliated – are being 

evaluated to determine harvest priorities. Chemical 

The North Central Region Risk Mapping Project expanded in 2004 to include states in the 

Northeastern and Southern Regions. 

resources to design and produce forest insect and disease risk models. 

MCM 

conducting forest health management activities. 

For additional information about his project, see: 

The 

www.mcgi.state.mi.us/forestHealth 

Prepared by Forest, Mineral & Fire Management Division 

Choristoneura pinus pinus) is considered the most significant 

suffering from drought or other stresses are very vulnerable to damage. 

and top-kill resulting from budworm defoliation creates fuel for intense wildfires. 

minimize budworm-caused tree 

mortality and reduce the threat of damaging wildfires, and create suitable conditions for 

The jack pine budworm epidemic has spread to 

141,646 acres of jack pine were moderately 

the Central U.P. included young plantations with 50­

80% reduction in total foliage. 

Approximately 171,798 acres were 

defoliated, down from 196,000 acres in 2003. Highrisk jack pine stands – those over 60 years of age that 

treatment of jack pine budworm infestations is rarely 

cost-effective. 

This effort, begun in 2000 in cooperation with USFS 

State & Private Forestry and, beginning this year, the USFS Forest Health Technology 

Enterprise Team, brings together forest health and Geographic Information System (GIS) 

Multi-criterion 

modeling (MCM) is used to predict the risk of major forest types becoming infested by 

(susceptibility) and dying from (vulnerability) various native and exotic forest pests. 

combines a variety of GIS data (criteria), including soil, tree, climate and forest health 

information, into detailed maps that will assist resource professionals in planning and 

http://www.fs.fed.us/foresthealth/mcm/ 

MDNR On-Line Pest Mapping Website is a convenient source of information about 

pest infestations in Michigan. In addition to the defoliation maps from the annual MDNR 

forest health aerial surveys, the site depicts the history of gypsy moth defoliation in 

Michigan since the 1980’s. Check it out at: