A COMPARISON OF THE INSECT COMMUNITIES 0F CONIFEROUS AND DECIDUOUS WOODLOTS Thesis hr the Dawn of M. S. MICHIGAN STATE UNIVERSITY AIIan D. Dawson 1955- IHESlS IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII r ,A COMPARISON OF THE INSECT communes or conmous AND IDECIDUOUS woomm's by Allen D. Dmon AN ABSTRACT Submitted to the School of Graduate Studies of nichigm state university of Agriculture and Applied Science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Entomolog 1955 ABSTRACT This study surveyed and compared qualitatively a sample of the insect species of three different forest insect comunities. The three forest types surveyed included a red pine woodlot, a red pine- white pine woodlot and an oak-hickory woodlot. Bach woodlot was approximately ten acres in size. The woodlots studied are located in the Kellogg Forest, Kalamazoo County, Michigan. They were surveyed, using the same methods in each, from June 20 to August 19, 1951. and from April 30 to June 19, 1955. ' collecting of the insects was done mainly by sweeping the herbs, shrubs, and lower tree strata with a thirty-centimeter insect net. other insects were taken after direct observation. In addi- tion, night collecting was done by using automobile headlights as attractants from various locations on logging roads throughout each area. An attempt was ends to collect as many insects as possible from each woodlot. Due to the nunbers involved and the fact that the surveys did not cover an entire year, the insects collected represent only a sample of the woodlot insect commities. Of the animals collected, only adult or identifiable imature forms of insects were recorded. Representives, as far as could be determined, of each species were mounted and identified to the lowest classification possible. The insects were then listed by woodlot and an attempt was made to determine which species were actually native to both the coniferous and deciduous woodlots. me out of five insect species recorded during the study was found to occur in both wood- lot types. However, review of the feeding habits and life histories of these species revealed that only one half of them, or about one out of ten insect species recorded, could be considered to be native to both the pine and oak-hickory woodlots. The majority of these insect species were found to be either scavengers, parasites or predators. Very few phytophagous insects were native to both wood- lot types. These findings led to the conclusion that, in general, insect enemies of forest stands are limited to either coniferous or deciduous stands and cannot attack both types of forest. Sumation of the nunbers of insect species recorded from each woodlot revealed that more insect species were recorded from the oak-hickory woodlot than fr’m either of the pine woodlots. More in- sect species were found in the red pine-white pine woodlot than in the red pine woodlot. It was concluded that the greater the numbers and types of vegetation occurring in the woodlot the greater was the number of insect species Occurring in the woodlot. This was supported by the fact that the oak-hickory woodlot had more vegetation than the red pine—white pine woodlot and it in turn had more vegetation than the red pine woodlot. It seemed probable that an increase in vegetation increased the numbers of ptwtophagous insect species and their predators and hence increased the total number of insect species semen to the woodlot. A COMPARISON OF THE INSECT COIIMUNITIES 0F CONIFEROUS AND DECIDUOUS WOODLOTS Allan D. Dawson ATHEIS Submitted to the School of Graduate Studies of Michigan state University of Agriculture and Applied science in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Department of Entomology 1955 . Ifihbs5 ACKNOWLEDGMENTS The author wishes to express his sincere appreciation and gratitude to Professors R. Hutson, I. F. Morofsky and to Associate Professor H. L. King, for invaluable guidance and encouragement throughout the study. He is also indebted to Assistand Professor R. L. Fischer for his assistance in insect identification and organisation of this study. Grateful acknowledgment is extended to the following indiv- iduals for their assistance in insect identification: Assistant Professor 0. Gwer of lichigan state University, Tendipedidae and Heleidae indentification; lichigan state graduate student 0. Taboada, cicadellidae indentification; and 3. [core of Detroit, nichigan, Lepidoptera identification. Special thanks is given to I. Drew, graduate student at lichigan state University, for prompt assistance in determining some Diptera specimens in the latter part of the study. Gratitude is expressed to Associate Professor 1.. Gysel of lichigan state University and I. Lemieln, w. K. Kellogg Forest, for their assistance in plant identification. The author is greatly indebted to his wife, Jane, and to his father, 8. B. Dawson, for their aid in insect collection and preparation of the draft of this paper. Sincere thanks is also given to the staff and the facilities provided by the I. K. Kellogg Gull Lake Biological Station and the W. K. Kellogg Forest. 5.35}: 181132 TABLE OF CONTENTS I. Introduction .............................. ....... ... 1 II- Historical Review................ ....... ..... ........ 2 III. Methods and Materials .......... ............ 5 Discussion ........................................... 12 V. Summary and conclusions .................. ............ 21 Appendix ............................................. 22 List Of References 00.00.000.00.........OOOOOOOOOOOOOO 7h INTRODUCTION It is generally agreed among biologists that particular animal species are closely associated with specific plant communities. The study of these relationships of animals and plants is termed bio-ecology. Past studies have shown the importance of these re- lationships in all faunal research. Very little research has been done on forest insect communities and their associations with specific forest plant communities by entomologists, even though forest; entomology is one of the most important branches of economic entomology. This paper is a study in forest insect bio- ecology. This study surveyed and compared qualitatively a sample of the insect species of three different forest insect communities. The three forest types surveyed included a red pine woodlot, a red pineawhite pine woodlot and an oak-hickory woodlot. The wood- lots studied are located in the Kellogg Forest, Kalamazoo County, Michigan. They were surveyed, using the same methods in each, from June 20 to August 19, l9Sh, and from.April 30 to June 19, 1955. This study was initiated while attending the summer School session at the Kellogg Gull Lake Biological Station during lQSh and continued throughout the season. HISTORICAL REVIEW Studies in forest entomology date back to the first part of the nineteenth century. The approach of the early studies and liter- ature derived from.interest in the insects themselves, rather than in their relationships to the forest. 'Work done in the last part of the nineteenth century and early twentieth century'began to show the importance of the forest's relationship to its insect population. Medern studies and literature in forest entomology stress this relationship but most of the recent work has approached the relationship from studies of insect enemies of specific forest tree species, group studies of certain forest insects, or life history studies of particular forest insect enemies and their parasites. Little work has been done on beneficial and other supposedly economically unimportant.forest insects in relation to the total ferest community. Even less research has been done in the field of forest insect bio-ecology, in which the forest insects are studied as an animal population or community in association with a definite forest plant community. The first insect bio-ecology studies were done in connection with two land animal bio-ecology studies made by Adams, (1906 and 1909), in which the insects were included as a part of the total animal community. Adams devoted particular attention to beetles along with other animals in relationship to their occurrence in various plant communities. Shelford (1907) traced the relation- ship of Cicindela species to various plant communities. A later study of animal communities by shelford (1913), associated various animal dominants, mostly insects, with one or more plant dominants in general plant communities. other biotic studies in terrestrial animal bio-ecology made during the past thirty years followed the pattern of Adams and studied the forest fauna with regards to the total animal community. Weese (l92h), and Smith (1928, 1930 and 1932), contributed a series of animal ecology studies in deciduous forests of central Illinois. Their works were largely quantitative and considered to a large extent the physical factors influencing the habitat. More recent studies have in general followed these same lines. The only study available in published literature that includes a comparison of coniferous and deciduous forest fauna is that of Blake (1926). His paper included a comparison of the land animal communities of a climax pine-hemlock forest and a climax elmdmaple forest. The pine-hemlock forest was studied during the summer of 1923. The elmpmaple forest study was made during the winter of 192h-l925. Both areas were located in central Illinois but not in the immediate vicinity of each other. The animal populations were sampled by the same methods in both areas.