In the late 1960\u27s an outbreak of yellow-green tortricid larvae occurred over hundreds of thousands of acres of red oaks in northeastern Lower Michigan. At first the insect was thought to be the fruit tree leafroller, Archips argyrospilus (Walker); adult specimens, however, were identified by Freeman as A. serniferanus Walker. On forest lands oak or pine was the preferred cover type. In urban areas, the problem was acute where red oaks were the predominant shade tree.
In 1969 and 1970 I observed this insect to learn about its life history, habits, and distribution. Besides regular field collections, some cage studies and laboratory rearings were done

Wilson, Louis F.

English

ValpoScholar

The Great Lakes Entomologist 
Volume 5 
Number 3 -- Fall 1972 Number 3 -- Fall 1972 Article 1 
August 1972 
Life History and Outbreaks of an Oak Leafroller, Archips 
Semiferanus (Lepidoptera: Tortricidae), in Michigan 
Louis F. Wilson 
USDA Forest Service, East Lansing, MI 
Follow this and additional works at: https://scholar.valpo.edu/tgle 
 Part of the Entomology Commons 
Recommended Citation 
Wilson, Louis F. 1972. "Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: 
Tortricidae), in Michigan," The Great Lakes Entomologist, vol 5 (3) 
Available at: https://scholar.valpo.edu/tgle/vol5/iss3/1 
This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. 
It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. 
For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. 
THE GREAT LAKES ENTOMOLOGIST 
LIFE HISTORY AND OUTBREAKS OF AN 
OAK LEAFROLLE R, ARCHIPS SEMIFERANUS 
(LEPIDOPTERA: TORTRICIDAE), IN MICHIGAN 
Louis F. Wilson 
North Central Forest Experiment Station 
USDA Forest Service 
East Lansing, ~ i c h i g a n l  
In the late 1960's an outbreak of yellow-green tortricid larvae occurred over 
hundreds of thousands of acres of red oaks in northeastern Lower Michigan. At first the 
insect was thought to be the fruittree leafroller, Archips argyrospilus (Walker); adult 
specimens, however, were identified by f re em an^ as A .  serniferanus Walker. On forest 
lands oak or pine was the preferred cover type. In urban areas, the problem was acute 
where red oaks were the predominant shade tree. 
In 1969 and 1970 I observed this insect to learn about its life history, habits, and 
distribution. Besides regular field collections, some cage studies and laboratory rearings 
were done. 
RECENT OUTBREAKS 
Freeman (1958) reports A. serniferanus feeding on Quercus spp. and Pyrus m i u s ,  
and says it is widely distributed but restricted to the southern half of the North 
American continent. The principal host species in Michigan are northern pin oak, Quercus 
ellipsoidalis E. J. Hill, and northern red oak, Q. rubra L., and the major outbreaks have 
been in the northeastern part of Lower Michigan where these oaks are abundant. Oaks of 
all ages are attacked (Fig. 1). 
The recent outbreak was first noticed in 1965 but aerial surveys made by the 
U.S.D.A. Forest Service were not able to detect defoliation that year. Heavy defoliation 
occurred in Oscoda County in 1966 and lesser defoliation occurred in surrounding 
counties. The outbreak reached its peak in 1968 when it extended over parts of Ogemaw, 
Oscoda, Montmorency, Crawford, Alcona, Iosco, and Roscommon Counties. The insect 
population declined in 1969 and collapsed in early summer of 1970. 
The heaviest mortality occurred near the end of the outbreak in 1969 in areas 
where heavy leafroller defoliation had occurred for 2 to 4 consecutive years. One or two 
late frosts during June that year weakened the trees sufficiently that healthy-looking 
refoliated trees began dying from the top down in August. Another late frost in early 
June of I970 appeared to be the major reason for the population collapse. The insects, 
then in the third and fourth instars, almost completely disappeared. Casual observations 
suggest that a sap borer, probably Agrilus bilineatus (Web,), may have killed some of the 
weakened trees as well. 
The extent and degree of damage was never fully assessed but at least one-half 
million acres of oaks were attacked and considerable dieback and tree mortality occurred 
where oaks had been heavily and repeatedly defoliated. Mortality was highest in 
Roscommon, Oscoda, AIcona, and Iosco Counties. 
A similar outbreak occurred over part of the same area from 1956 to 1 9 5 8 . ~  At 
that time it also was thought to be the fruittree leafroller, but there is good evidence that 
'office maintained in cooperation with Michigan State University. 
2 ~ .  N Freeman, Ottawa, Ontario, Canada. 
%ate and Federal insect situation reports, unpublished. 
1
Wilson: Life History and Outbreaks of an Oak Leafroller, Archips Semifera
Published by ValpoScholar, 1972
7 2 THE GREAT LAKES ENTOMOLOGIST Vol. 5,  No. 3 
Fig. 1. Young oaks completely defoliated by A. semiferanus in 1968 in Oscoda County, 
Michigan, at peak of the outbreak. 
it was A. semiferanus as in the 1965-70 outbreak. The population started to build up in 
1955, and in 1956 the insect defoliated oaks on 214,500 acres in Crawford County. The 
infestation peaked in 1957 when it covered some 350,000 acres in parts of Crawford, 
Roscommon, Ogemaw, and Oscoda Counties. Branch mortality occurred that year. By 
2
The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1
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1972 THE GREAT LAKES ENTOMOLOGIST 73 
1958 some trees had died--especially on the poorer oak sites. The drought that occurred 
from 1955 to  1959 undoubtedly contributed to  the mortality. A severe frost that 
occurred when the leaves were several inches long may have been the major cause of the 
insect population collapse in 1958. 
LIFE HISTORY 
The oak leafroller in univoltine in Michigan and overwinters in the egg stage. The 
life history for Alcona County for 1969-11970 is depicted in Fig. 2. 
Fig. 2. Seasonal development of A. semiferanus on oak in Alcona County, Michigan. 
STAGE WINTER APRIL MAY JUNE JULY AUG. 
EGG 
FIRST INSTAR 
SECOND INSTAR 
THIRD INSTAR 
FOURTH INSTAR 
F I F T H  INSTAR 
PUPA 
ADULT 
EGG 
Egg Stage 
Female moths emerge and oviposit through most of July and early August. Eggs 
are laid in a compact mass on the bark usually to  the side of or just below a twig crotch 
(Fig. 3B). The mass is oval and covered with erect or semi-erect tan scales from the 
female's abdomen (Fig. 3A). Old egg masses are grayish and frequently devoid of scales 
(Fig. 3B). Twenty-six egg masses examined in autumn of 1969 revealed a mean of 48 
eggslmass (range 15-125). Mean egg mass dimensions were 4.2 mm X 2.8 mm. The 
diameter of the twig at the oviposition site averaged 16 mm but varied from 5 mm to 
25 mm. One twig collected had four egg masses around the same crotch with three 
SEPT. 
together and overlapping. They appeared to be from three separate females. 
WINTER 
All eggs, except parts of a few on the periphery, are well concealed beneath the 
scales on the egg mass. Eggs appear brown, probably from the adhesive coating them that 
holds the scales tightly. The eggs vary in shape and dimensions depending on their 
locality in the mass. Those on the periphery are flattened and oval and measure about 
0.63 X 0.55 mm at the widest and narrowest diameters. Those in the center are "on 
edge" and if cut from above resemble the cells of a honeycomb. They measure about 
0.35 mm wide by 0.69 mm deep. 
Larval Stages 
Five larval instars were indicated from a frequency histogram of 1,494 head 
capsule width measurements and by comparing living larvae with cast head capsules in 
3
Wilson: Life History and Outbreaks of an Oak Leafroller, Archips Semifera
Published by ValpoScholar, 1972
74 THE GREAT LAKES ENTOMOLOGIST 
Fig. 3. Egg masses of A. semiferanus: (A) egg masses on oak bark covered with scales 
from female moth; (B) hatched egg mass located below and to  the side of twig 
crotch of oak. 
their Ieafrolls. First-instar measurements were made on larvae emerging from egg masses 
that were placed in jars in the field in autumn and brought into the laboratory in the 
spring. Behavior and development observations were made on two young oaks caged in 
the field, and one small sapling potted in the laboratory. Mean and range (in mm) of 
head capsule measurements for the 1,494 larvae for the five instars were: 
No. head Mean width 
Instar capsules and S.D. Range 
I 3 7 0.272 * .010 0.267 - 0.298 
I1 193 0.464 + .033 0.393 - 0.565 
111 239 0.719 + .075 0.581 - 0.864 
IV 305 1.075 .099 0.879 - 1.319 
V 720 1.734 + ,123 1.366 - 2.010 
The first-instar larva ecloses in mid-May by chewing an exit hole in the upper side 
(or end) of the egg. The newly emerged larva is greenish-yellow with a shiny bIack head. 
First eclosion appears to  be synchronized closely with bud-break of oak; the leaves are 
about 1.2 mm or shorter at emergence time. The larva seeks out these emerging leaf 
clusters. It then spins a web within the protective concealing folds of the leaves (Fig. 4A) 
and skeletonizes small patches of the upper leaf surfaces within the webbed area. The leaf 
edges may be nibbled on as well. Later the larva moves to new leaves or leaf clusters as 
4
The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1
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1972 THE GREAT LAKES ENTOMOLOGIST 75 
Fig. 4. Some leaf webbing and rolling habits of A. semiferanus: (A) first-instar larva 
webbing in folds of young leaf cluster; (B)webbing and folding of leaf of 
late-emerging first-instar larva; (C,D) leafrolling, webbing, and feeding patterns of 
thud- to  fifth-instar larvae; (E) tightly rolled leaf of last-instar larva (occasionally 
encountered). 
the food supply is consumed or dies. A lateeclosing larva encounters leaves that are 
further advanced in development and thus webs two or more touching leaf surfaces 
together, or it rolls the leaf edge t o  form a partly closed fold or cylinder (Fig. 4B). 
Several young larvae may occupy the same leaf or leaf cluster at this time. 
The second-instar larva appears about the thud week in May. The cast first-instar 
head capsule often remains in the webbing. During this stadium the leaf is rolled more, or 
new leaves are added as they are needed for shelter and food. Free feeding occurs along 
the edges and between the large veins during the second and remaining stadia. The leaf or 
leaf cluster may be rolled lengthwise, crosswise, or just along one side to  form a 
cylindrical cavity. Typical habits are depicted in Figures 4C, D, E, and Figure 5. Within 
the leafrolls, only one side is lined with silk; the other side has at  most a few strands. 
Outside, a few compact bundles of silk strands maintain the roll structure (Figs. 4C, D, 
E). Both the leafroll cavity and webbing are relatively free from debris with only an 
occasional frass particle or head capsule. 
Mature larvae exhibit typical torticid behavior when disturbed. They retreat rapidly 
in reverse and drop down on their silk threads. Those dropping over water attract trout 
and other fish. Some fishermen who noticed the activity of this "greeny-worm", as they 
called them, tied trout flies to imitate them during the outbreak. 
Pupa and Adult Stages 
The pupa appears in the leafroll in late June. It is firmly attached to the webbing 
5
Wilson: Life History and Outbreaks of an Oak Leafroller, Archips Semifera
Published by ValpoScholar, 1972
THE GREAT LAKES ENTOMOLOGIST 
Fig. 5. Typical leafrolling of last two instar larvae of A. semiferanus. 
by several terminal abdominal hooks. In early July the adult ecloses and vacates the 
leafroll through either end of the cavity. Moths were occasionally observed on the foliage 
during the day and were only seen in flight when disturbed. Oviposition behavior was not 
observed. Freeman (1958) notes that the large brush of closely packed, corrugated scales 
on the undersurface of the female is likely the group used to cover the eggs. 
DISCUSSION 
Outbreaks of A. semiferanus appear to be short-lived, seldom lasting more than 5 
years in Michigan. Frost and drought contribute both to oak mortality and leafroller 
decline. A current outbreak of this insect in ~ennsylvania? which erupted in 1967, 
continued through 1971 but showed signs of decline by 1972 from parasites and 
predators. Degree and extent of mortality are not known for Michigan, but the 
Pennsylvania outbreak, which is probably twice as devastating, covered over 1 million 
acres by 1971; losses totaling $56 million in stumpage value alone are predicted by the 
end of 1972. 
It is more difficult to assign an economic loss for Michigan. On forest lands some 
of the oak killed is scrub oak that is occasionally underplanted with red pine. Where 
management plans included release of the pine simply by killing the oak, the mortality of 
oak here perhaps constituted an economic gain. Other plans included commercially 
harvesting the oak for pulpwood. From the wildlife standpoint the oak provided acorns. 
In urban areas such as in and near the town of Mio, which relies heavily on tourism, thc 
4~ennsylvania Forest Pest Reporter 49 ( 1  972). 
6
The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1
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1972 THE GREAT LAKES ENTOMOLOGIST 7 7 
insect denuded and killed many of the predominant shade trees. Dead oaks along 
roadsides were aesthetically unpleasing to residents and tourists alike. 
LITERATURE CITED 
Freeman, T. N. 1958. The Archipinae of North America (Lepidoptera: Tortricidae). Can. 
Entomol. Suppl. 7, p. 20-21. 
7
Wilson: Life History and Outbreaks of an Oak Leafroller, Archips Semifera
Published by ValpoScholar, 1972


Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: Tortricidae), in Michigan

Valparaiso University

The Great Lakes Entomologist Volume 5 Number 3 -- Fall 1972 Number 3 -- Fall 1972 Article 1 August 1972 Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: Tortricidae), in Michigan Louis F. Wilson USDA Forest Service, East Lansing, MI Follow this and additional works at: https://scholar.valpo.edu/tgle  Part of the Entomology Commons Recommended Citation Wilson, Louis F. 1972. "Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: Tortricidae), in Michigan," The Great Lakes Entomologist, vol 5 (3) Available at: https://scholar.valpo.edu/tgle/vol5/iss3/1 This Peer-Review Article is brought to you for free and open access by the Department of Biology at ValpoScholar. It has been accepted for inclusion in The Great Lakes Entomologist by an authorized administrator of ValpoScholar. For more information, please contact a ValpoScholar staff member at scholar@valpo.edu. THE GREAT LAKES ENTOMOLOGIST LIFE HISTORY AND OUTBREAKS OF AN OAK LEAFROLLE R, ARCHIPS SEMIFERANUS (LEPIDOPTERA: TORTRICIDAE), IN MICHIGAN Louis F. Wilson North Central Forest Experiment Station USDA Forest Service East Lansing, ~ i c h i g a n l  In the late 1960's an outbreak of yellow-green tortricid larvae occurred over hundreds of thousands of acres of red oaks in northeastern Lower Michigan. At first the insect was thought to be the fruittree leafroller, Archips argyrospilus (Walker); adult specimens, however, were identified by f re em an^ as A .  serniferanus Walker. On forest lands oak or pine was the preferred cover type. In urban areas, the problem was acute where red oaks were the predominant shade tree. In 1969 and 1970 I observed this insect to learn about its life history, habits, and distribution. Besides regular field collections, some cage studies and laboratory rearings were done. RECENT OUTBREAKS Freeman (1958) reports A. serniferanus feeding on Quercus spp. and Pyrus m i u s ,  and says it is widely distributed but restricted to the southern half of the North American continent. The principal host species in Michigan are northern pin oak, Quercus ellipsoidalis E. J. Hill, and northern red oak, Q. rubra L., and the major outbreaks have been in the northeastern part of Lower Michigan where these oaks are abundant. Oaks of all ages are attacked (Fig. 1). The recent outbreak was first noticed in 1965 but aerial surveys made by the U.S.D.A. Forest Service were not able to detect defoliation that year. Heavy defoliation occurred in Oscoda County in 1966 and lesser defoliation occurred in surrounding counties. The outbreak reached its peak in 1968 when it extended over parts of Ogemaw, Oscoda, Montmorency, Crawford, Alcona, Iosco, and Roscommon Counties. The insect population declined in 1969 and collapsed in early summer of 1970. The heaviest mortality occurred near the end of the outbreak in 1969 in areas where heavy leafroller defoliation had occurred for 2 to 4 consecutive years. One or two late frosts during June that year weakened the trees sufficiently that healthy-looking refoliated trees began dying from the top down in August. Another late frost in early June of I970 appeared to be the major reason for the population collapse. The insects, then in the third and fourth instars, almost completely disappeared. Casual observations suggest that a sap borer, probably Agrilus bilineatus (Web,), may have killed some of the weakened trees as well. The extent and degree of damage was never fully assessed but at least one-half million acres of oaks were attacked and considerable dieback and tree mortality occurred where oaks had been heavily and repeatedly defoliated. Mortality was highest in Roscommon, Oscoda, AIcona, and Iosco Counties. A similar outbreak occurred over part of the same area from 1956 to 1 9 5 8 . ~  At that time it also was thought to be the fruittree leafroller, but there is good evidence that 'office maintained in cooperation with Michigan State University. 2 ~ .  N Freeman, Ottawa, Ontario, Canada. %ate and Federal insect situation reports, unpublished. 1Wilson: Life History and Outbreaks of an Oak Leafroller, Archips SemiferaPublished by ValpoScholar, 19727 2 THE GREAT LAKES ENTOMOLOGIST Vol. 5,  No. 3 Fig. 1. Young oaks completely defoliated by A. semiferanus in 1968 in Oscoda County, Michigan, at peak of the outbreak. it was A. semiferanus as in the 1965-70 outbreak. The population started to build up in 1955, and in 1956 the insect defoliated oaks on 214,500 acres in Crawford County. The infestation peaked in 1957 when it covered some 350,000 acres in parts of Crawford, Roscommon, Ogemaw, and Oscoda Counties. Branch mortality occurred that year. By 2The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1https://scholar.valpo.edu/tgle/vol5/iss3/11972 THE GREAT LAKES ENTOMOLOGIST 73 1958 some trees had died--especially on the poorer oak sites. The drought that occurred from 1955 to  1959 undoubtedly contributed to  the mortality. A severe frost that occurred when the leaves were several inches long may have been the major cause of the insect population collapse in 1958. LIFE HISTORY The oak leafroller in univoltine in Michigan and overwinters in the egg stage. The life history for Alcona County for 1969-11970 is depicted in Fig. 2. Fig. 2. Seasonal development of A. semiferanus on oak in Alcona County, Michigan. STAGE WINTER APRIL MAY JUNE JULY AUG. EGG FIRST INSTAR SECOND INSTAR THIRD INSTAR FOURTH INSTAR F I F T H  INSTAR PUPA ADULT EGG Egg Stage Female moths emerge and oviposit through most of July and early August. Eggs are laid in a compact mass on the bark usually to  the side of or just below a twig crotch (Fig. 3B). The mass is oval and covered with erect or semi-erect tan scales from the female's abdomen (Fig. 3A). Old egg masses are grayish and frequently devoid of scales (Fig. 3B). Twenty-six egg masses examined in autumn of 1969 revealed a mean of 48 eggslmass (range 15-125). Mean egg mass dimensions were 4.2 mm X 2.8 mm. The diameter of the twig at the oviposition site averaged 16 mm but varied from 5 mm to 25 mm. One twig collected had four egg masses around the same crotch with three SEPT. together and overlapping. They appeared to be from three separate females. WINTER All eggs, except parts of a few on the periphery, are well concealed beneath the scales on the egg mass. Eggs appear brown, probably from the adhesive coating them that holds the scales tightly. The eggs vary in shape and dimensions depending on their locality in the mass. Those on the periphery are flattened and oval and measure about 0.63 X 0.55 mm at the widest and narrowest diameters. Those in the center are "on edge" and if cut from above resemble the cells of a honeycomb. They measure about 0.35 mm wide by 0.69 mm deep. Larval Stages Five larval instars were indicated from a frequency histogram of 1,494 head capsule width measurements and by comparing living larvae with cast head capsules in 3Wilson: Life History and Outbreaks of an Oak Leafroller, Archips SemiferaPublished by ValpoScholar, 197274 THE GREAT LAKES ENTOMOLOGIST Fig. 3. Egg masses of A. semiferanus: (A) egg masses on oak bark covered with scales from female moth; (B) hatched egg mass located below and to  the side of twig crotch of oak. their Ieafrolls. First-instar measurements were made on larvae emerging from egg masses that were placed in jars in the field in autumn and brought into the laboratory in the spring. Behavior and development observations were made on two young oaks caged in the field, and one small sapling potted in the laboratory. Mean and range (in mm) of head capsule measurements for the 1,494 larvae for the five instars were: No. head Mean width Instar capsules and S.D. Range I 3 7 0.272 * .010 0.267 - 0.298 I1 193 0.464 + .033 0.393 - 0.565 111 239 0.719 + .075 0.581 - 0.864 IV 305 1.075 .099 0.879 - 1.319 V 720 1.734 + ,123 1.366 - 2.010 The first-instar larva ecloses in mid-May by chewing an exit hole in the upper side (or end) of the egg. The newly emerged larva is greenish-yellow with a shiny bIack head. First eclosion appears to  be synchronized closely with bud-break of oak; the leaves are about 1.2 mm or shorter at emergence time. The larva seeks out these emerging leaf clusters. It then spins a web within the protective concealing folds of the leaves (Fig. 4A) and skeletonizes small patches of the upper leaf surfaces within the webbed area. The leaf edges may be nibbled on as well. Later the larva moves to new leaves or leaf clusters as 4The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1https://scholar.valpo.edu/tgle/vol5/iss3/11972 THE GREAT LAKES ENTOMOLOGIST 75 Fig. 4. Some leaf webbing and rolling habits of A. semiferanus: (A) first-instar larva webbing in folds of young leaf cluster; (B)webbing and folding of leaf of late-emerging first-instar larva; (C,D) leafrolling, webbing, and feeding patterns of thud- to  fifth-instar larvae; (E) tightly rolled leaf of last-instar larva (occasionally encountered). the food supply is consumed or dies. A lateeclosing larva encounters leaves that are further advanced in development and thus webs two or more touching leaf surfaces together, or it rolls the leaf edge t o  form a partly closed fold or cylinder (Fig. 4B). Several young larvae may occupy the same leaf or leaf cluster at this time. The second-instar larva appears about the thud week in May. The cast first-instar head capsule often remains in the webbing. During this stadium the leaf is rolled more, or new leaves are added as they are needed for shelter and food. Free feeding occurs along the edges and between the large veins during the second and remaining stadia. The leaf or leaf cluster may be rolled lengthwise, crosswise, or just along one side to  form a cylindrical cavity. Typical habits are depicted in Figures 4C, D, E, and Figure 5. Within the leafrolls, only one side is lined with silk; the other side has at  most a few strands. Outside, a few compact bundles of silk strands maintain the roll structure (Figs. 4C, D, E). Both the leafroll cavity and webbing are relatively free from debris with only an occasional frass particle or head capsule. Mature larvae exhibit typical torticid behavior when disturbed. They retreat rapidly in reverse and drop down on their silk threads. Those dropping over water attract trout and other fish. Some fishermen who noticed the activity of this "greeny-worm", as they called them, tied trout flies to imitate them during the outbreak. Pupa and Adult Stages The pupa appears in the leafroll in late June. It is firmly attached to the webbing 5Wilson: Life History and Outbreaks of an Oak Leafroller, Archips SemiferaPublished by ValpoScholar, 1972THE GREAT LAKES ENTOMOLOGIST Fig. 5. Typical leafrolling of last two instar larvae of A. semiferanus. by several terminal abdominal hooks. In early July the adult ecloses and vacates the leafroll through either end of the cavity. Moths were occasionally observed on the foliage during the day and were only seen in flight when disturbed. Oviposition behavior was not observed. Freeman (1958) notes that the large brush of closely packed, corrugated scales on the undersurface of the female is likely the group used to cover the eggs. DISCUSSION Outbreaks of A. semiferanus appear to be short-lived, seldom lasting more than 5 years in Michigan. Frost and drought contribute both to oak mortality and leafroller decline. A current outbreak of this insect in ~ennsylvania? which erupted in 1967, continued through 1971 but showed signs of decline by 1972 from parasites and predators. Degree and extent of mortality are not known for Michigan, but the Pennsylvania outbreak, which is probably twice as devastating, covered over 1 million acres by 1971; losses totaling $56 million in stumpage value alone are predicted by the end of 1972. It is more difficult to assign an economic loss for Michigan. On forest lands some of the oak killed is scrub oak that is occasionally underplanted with red pine. Where management plans included release of the pine simply by killing the oak, the mortality of oak here perhaps constituted an economic gain. Other plans included commercially harvesting the oak for pulpwood. From the wildlife standpoint the oak provided acorns. In urban areas such as in and near the town of Mio, which relies heavily on tourism, thc 4~ennsylvania Forest Pest Reporter 49 ( 1  972). 6The Great Lakes Entomologist, Vol. 5, No. 3 [1972], Art. 1https://scholar.valpo.edu/tgle/vol5/iss3/11972 THE GREAT LAKES ENTOMOLOGIST 7 7 insect denuded and killed many of the predominant shade trees. Dead oaks along roadsides were aesthetically unpleasing to residents and tourists alike. LITERATURE CITED Freeman, T. N. 1958. The Archipinae of North America (Lepidoptera: Tortricidae). Can. Entomol. Suppl. 7, p. 20-21. 7Wilson: Life History and Outbreaks of an Oak Leafroller, Archips SemiferaPublished by ValpoScholar, 1972

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Life History and Outbreaks of an Oak Leafroller, Archips Semiferanus (Lepidoptera: Tortricidae), in Michigan

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