Forest Fragmentation and Its Effects on Arthropod Populations in Small Vs

FOREST FRAGMENTATION AND ITS EFFECTS ON ARTHROPOD POPULATIONS IN SMALL VS. LARGE FORESTS IN NORTHWEST OHIO

Mary C. Baumgardner

A Thesis

Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of

MASTER OF SCIENCE

May 2007

Committee:

Daniel M Pavuk, Advisor

Helen Michaels

Rex Lowe

ii ABSTRACT

Dr. Daniel M. Pavuk, Advisor

The loss of biodiversity is a large challenge facing the conservation biologist. Many species of arthropods are susceptible to displacement, starvation or complete decimation when human activities, such as development, occur within or near their habitat. Insects and arthropods are not

valued by the average person and are typically considered to be a frightening nuisance. The

value of arthropods cannot be overstated. Arthropods perform services for ecosystems that are

needed by plants and other organisms. For example, the elimination of insect pollinators would

halt much of plant fruit and seed production and cause a reduction in plant repopulation.

Detritivorous insects are vital to plants for their distribution of nutrients into soil. Larger forested areas should contain a greater abundance of arthropods and more species than smaller forests, according to the theory of island biogeography. The theory of island biogeography

involves the study of distribution of species and community composition on islands. Various patches of small and large forests suggest islands of different sizes (Smith and Smith 2001). I calculated species richness, arthropod abundance and graphed species to forest area comparisons.

My nine study sites varied from 1.6 to 1500 hectares. Most of the sites were surrounded by agricultural areas with roads or highways bordering one or more sides of the forests creating a possible barrier. Some of the larger sites also had roads cutting through the forest. Arthropods were sampled four times at each of the nine study sites in late spring and summer of 2005 and

2006 using the beat-stick method for collection. Once arthropods were placed into a zippered plastic bag with the sample of the tree or shrub and preserved in the freezer until sorting and identification could begin. There was little variation in abundance or species richness; small iii forests tended to have only slightly higher abundance numbers than the larger forest sites. The only group of insects that showed greater species richness in small vs. large forests was the order

Orthoptera (p<0.05). Sorensen’s Similarity Index showed low similarity in study sites. The results of this study could be useful in land management; more studies need to be completed to aid in the total understanding of species distribution, community structure and optimal habitat requirements for arthropods.

iv ACKNOWLEDGEMENTS

I would like to express my gratitude to my committee, Dr. Daniel Pavuk, Dr. Helen Michaels, and Dr. Rex Lowe. I would like to thank the Carter family and Bowling Green State University for access to woodlots on their property. I would like to also thank Mr. John Jaeger, Director of

Natural Resources of the Metroparks Toledo Area and Mr. Chris Smalley, Stewardship Director, of the Wood County Park District for their permission to complete data collection at Oak

Openings, Fuller Preserve, Secor Woods, Bradner Preserve, and Pearson Park. I would also like to thank my friends for their support and understanding. I would like to offer a special thanks to my lab associates, Laura Hughes-Williams, Melanie Bergolc and Rostern Tembo for their assistance, encouragement, compassion, and especially their humor. An extra thank you to

Melanie Bergolc for sharing her talents of the computer. Thank you, Helen Michaels, for your guidance with plant identification. Additional thanks to Dr. Dan Pavuk and Rostern Tembo for their assistance in the field, in preparation for this paper. v TABLE OF CONTENTS

Section Page

INTRODUCTION………………………………………………………………………………...1

METHODS………………………………………………………………………………………..6

RESULTS & ANALYSIS...…………………………………………………….……...………..11

DISCUSSION……………………………………………………………………………………14

LITERATURE CITED………………………………………………………….…...………..…24

TABLES & FIGURES

Table # Page

1 TREES & FAMILIES COLLECTED FROM………………………...... 32 (Showing scientific and common name)

2 ORDERS OF ARTHROPODS COLLECTED……………………………...…………..35 (Showing scientific and common names and descriptive terms)

3 WOODLOT NAMES …………………………………………………………....……..36 (Including county location, woodlot size in acres and hectares, number of times collected)

4 SUMMARY OF DIVERSITY INDICES……………………………….…….…..……..37 (Shannon Index and Evenness).

5 SORENSON’S SIMILARITY INDEX SUMMARY TABLE………………..……..…..38

6 SUMMARY TABLE PER DATE……………………………………………….………39 Shannon and Evenness calculations for each collection date)

7 COLLECTION SUMMARY CHART……………………………………...... 40 (Site name, area in (ha), total species per site, total arthropod abundance, Shannon Index and Evenness for all collections at that site)

(Cont.) vi

8 TWO-SAMPLE T-TEST FOR SMALL VS LARGE FORESTS……………………….41

9 TWO-SAMPLE T-TEST FOR EVENNESS FOR LARGE VS SMALL FORESTS…………………………………………………………………..41

10 TWO-SAMPLE T-TEST FOR TOTAL SPECIES OF LARGE VS SMALL FORESTS……………………………………………………………….…41

11 TWO-SAMPLE T-TEST FOR TOTAL ARTHROPODS OF LARGE VS SMALL FORESTS………………………………………………….…………..41

12 SUMMARY CHART……………………………………………………………....…...42 (Including arthropod order, large or small forest site, mean species richness, standard deviation, standard error mean, P-value and T-value)

13 TREE OR SHRUB COLLECTED FROM & TOTAL ARTHROPODS COLLECTED FROM THAT PLANT SPECIES PER SITE……………………….43

14 CUMULATIVE ARTHROPOD SPECIES LIST PER SITE……………………….…..48

Figure # Page

1 PIE CHART SHOWING PERCENT OF ARTHROPODS COLLECTED AND DIVIDED BY ORDER………………………………………………………...59

2 BAR GRAPHS (A-J), DONE BY ORDER AND COMPARING THE NUMBER PER ODER TO EACH SITE………………………………………...….60

3 FITTED LINE PLOT WITH TOTAL SPECIES VS. HECTARES……………………..65

1 INTRODUCTION

“The nature of land-use change in recent decades has not only resulted in a dramatic decrease

in total forest cover, but also in an increasingly skewed size-distribution of forest remnants.

Forest fragmentation is an important process contributing to the present-day concerns over biodiversity and rates of extinction. There is now urgent need to identify the key effects of forest fragmentation on biotic systems” (Didham et. al., 1996).

Substantial changes in vegetation over a long period of time have caused extensive alterations in the landscape and have led to changes in insect biodiversity. The heterogeneity of an area has been strongly correlated with the number of species in an area and patterns of species diversity are also associated with patterns of spatial and temporal variation. Abundance in biomass and diversity of plant and animal species, ecosystem stability, and variation and diversity of habitats add to species diversity. When the complete clearing of forests continues at the present rate and those ecosystems are replaced with a monoculture of trees or a food crop such as soy beans, the result is a reduction in insect species diversity and abundance (Ananthakrishnan, 2000). Even though specialization of plant feeding insects could not generate diversity by itself, a correlation

between resource diversity and species richness with specialization adds the driving force that

may lead to diversification of insects (Janz et al., 2006).

Over the last decade, much concern has been given to the decline in pollinator insects. The

decline in abundance and diversity of pollinators has been caused by different types of

anthropogenic disturbances. Deforestation and habitat fragmentation with open, sparse growth

within the understory has resulted in significant declines in pollinator flower visitation.

Pollinator flower visits were reduced by more than twofold as distances from the flowers to the

forest increased. The number of pollinator insects was diminished and a diversity reduction

2 occurred that led to a more homogeneous group of pollinators. Evidence of this was observed as the distance from the flowers to the forests’ edge increased (Chacoff et al., 2006).

Hundreds of species of insects and arthropods have the capability of survival on the fragmented remnants free of human habitation (Hendericson, 1930; Evans, 1975; Panzer, 1988;

Panzer et al., 2000). However, many arthropod species are incapable of habiting human- dominated landscapes (Panzer et al., 1995; Panzer, 2000). Isolated as small populations on what are essentially small habitat islands, these species are remnant-requiring or “remnant-dependent” organisms (Panzer et al., 1995; 1997; 2000). Landscapes are defined as heterogeneous land areas composed of clusters of interacting ecosystems (Pichcourt et al, 2005). The quality and spatial structure of landscapes since the 1950s have evolved under the influence of human activities to endanger a large number of species. These activities include the alterations by humans, such as poor land use patterns, industrial activity, and agriculture or natural disturbances. Habitat fragmentation is one of the major causes of biodiversity erosion (Pichcourt et al., 2005). The investigation of forest arthropod dynamics is discussed in numerous studies which consider the behavior of populations as a function of the condition of a forest. Insect populations can demonstrate a wide spectrum of patterns, from nearly stationary to oscillating and quasi-chaotic

(Bazykin et al., 1995).

Studies of watershed nutrient dynamics have indicated that changes on vegetation following disturbance tend to regulate watershed nutrient budgets by cycling nutrients in proportion to the potential for nutrient loss from the ecosystem (Bormann 1979, Gorham et al. 1979). Insect population dynamics have appeared capable of regulating nutrient cycling through their influence on vegetation and the soil-litter (Schowalter et al. 1981, Mattson 1975, O’Neil 1976).

3 In North Carolina the effects of clear cutting on an undisturbed hardwood forest and its arthropods were studied during the first two growing seasons following cutting. Arthropod numbers increased 23-fold with aphid species and ant species increased 6-fold. However, these groups of arthropods had lower nutrient concentrations. Arthropod potassium (K) concentrations were 33% lower on the clear cut area, sodium (Na), magnesium (Mg), and calcium concentrations were reduced significantly. Two years after the clear cutting occurred, nutrient retention was observed because of possible increased rate of nutrient cycling through consumption of the reduction on availability of the nutrients (Schowalter et al. 1981).

The impact of global climate change on herbivorous insects could influence their interactions within the forests. “Herbivorous insects and pathogens impact the species composition, ecosystem function, and socioeconomic value of forests. Herbivores and pathogens are an integral part of forests, but sometimes produce undesirable effects and a degradation of forest resources. Climatic change could alter patterns of disturbance from herbivores and pathogens through: (1) direct effects on the development and survival of herbivores and pathogens; (2) physiological changes in tree defenses; and (3) indirect effects from changes in the abundance of natural enemies, for example, parasitoids of insect herbivores, and mutualists, like insect vectors of tree pathogens, and competitors. Changes in forest disturbance can produce feedback to climate through affects on water and carbon flux in forest ecosystems. One scenario is that climate warming may increase further climate warming (Ayers et al 2000).”

Recent land-use change in many parts of the world have greatly reduced natural habitats and altered the size-distribution of remaining fragments. Understanding the effects of such change on extinction rates of populations and dispersal patterns is critical because these processes

4 influence the persistence of regional populations, the structure within biological communities, and the function of ecosystems (Andrén 1994, Gibb 2001, Rahel 1990).

Fragmentation issues are very important to forest ecosystems and their insect and arthropod faunas (Didham et al. 1996). There continues to be an increase in the fragmentation of forested lands. Fragmentation is a continuing process which encompasses the predominantly human caused degradation and destruction of natural areas. This typically occurs for reasons such as development of farm lands, to increase food production for the growing human population. Land development for industry to manufacture and or sell goods, which includes the construction of factories or manufacturing plants, distribution centers, and retail outlets. New housing starts and construction of apartment complexes, and roads to house the increasing human population, all of these examples contribute to the destruction of natural areas.

Many biological processes critical to forest ecosystem function such as seed predation, pollination, and decomposition, these are all mediated by insects (Didham et al 1996). “Drastic declines in species richness dung and carrion beetle (Scarbaeinae) communities and abundances have been documented, including corresponding rates of reduction with decomposition (Klein

1989, Gibbs 2001).” Changes in termite species diversity was also documented. Declines of termite populations have been noted at up to 3-fold within forest remnants (Gibbs 2001, Souza et al. 1994). Forest fragments in urban areas support greatly reduced butterfly faunas in part because of a reduction in plant nectar availability (Rodrigues et al. 1993).

The purpose of this study was to determine the effects of forest fragmentation on arthropod communities of large and small forest areas in Northwest Ohio. The theory of island

5 biogeography led me to the hypothesis that there would be a greater number of arthropods and greater species richness in larger forests than in smaller forests.

6 METHODS

Study Sites and Sampling Protocols

In order to research the diversity of forest arthropods, I chose study sites that were located in

Lucas and Wood Counties in northwest Ohio. Lucas County is bordered on the south by Wood

County and to the north by Michigan. None of the study sites were more than 45 minutes driving time from Bowling Green, Ohio. Roads and major highways were built along at least one and sometimes several sides of each of the forest study sites. Where roads were not present at edges of the forested sites, farmland was typically present, which was commonly planted with corn (Zea mays), soybeans (Glycine max), or wheat (Triticum aestivum), and housing developments occupied more than one side of each of the forested preserves. Human activity surrounded every study site. Northwest Ohio is well populated and the only natural areas that are still present are predominantly up to 50 hectares, with the majority under 20 ha. These forested areas exist in an isolated and fragmented pattern with no connectivity present between sites. Within the two counties, nine study sites were chosen. Land use history of these properties was assumed to be 100 plus years in its present state, many of the trees were quite large in height as well as diameter. The sites were scattered with a large number of young and sapling trees and some with diameters of less than 18 inches and were nearly the same height as the older, larger and thicker trees. A complete spies list of the trees and woody shrubs that were collected from was compiled and can be seen on (Table 1). The sites were categorized according to the amount of acreage at each site. Sites were classified as a large forest lot where there were

>53 ha <1600 ha. Small forest lots were <53 ha. Arthropods from woody shrubs and trees and a significant sample of each plant that the arthropods occupied, were collected and kept together. 7 According to botanist Dr. Helen Michaels of Bowling Green State University, it was important to

sample a large enough piece of the plant to observe the leaves, stems, and branches of the tree or

shrub was collected to make accurate identification of a plant species possible. Observation of

not only the individual leaf, but also the arrangement several of leaves on the stem, including the

construction, color, and texture are critical for correct identification of each tree and shrub

species. Each plant sample and its occupying arthropods were collected and deposited together

in the same one gallon Zip-Lock plastic freezer bag. The collection site and date were written on

each bag with a water-proof marker. The bags were gathered, placed in one larger 13 gallon

trash bag and stored in the freezer in the BGSU herbarium until sorting and identification could be completed.

Collecting took place in the late springs and summers of 2005 and 2006. A total of four

visits per site were completed for each of the nine forest areas. When student help was available,

two collections could be completed on the same date, one from the researcher and one from the

student worker. Care was taken to work in two different areas of the woods and never to overlap

collection areas.

Small forests were Fuller Preserve, Carter Woods, Bradner Preserve and the Bowling Green

State University Environmental Wood Lot (ENV), all located in Wood County and Pearson

Park, located in Lucas County. The large forests were Oak Openings and Secor Woods in Lucas

County, and Baldwin Preserve and Steidtman Woods in Wood County, see (Table 3). These

study sites were similar in that they were predominantly occupied by a variety of deciduous trees

and shrubs. Several species of oak (Quercus spp.), maple (Acer spp.), hickory (Carya spp.), and

elm (Ulmus spp.) were represented most frequently. Species such as dogwood (Cornus spp.),

apple (Malus spp.), cherry (Prunus spp.), locust (Robinia spp.), sumac (Rhus spp.), paw-paw 8 (Asimina spp.), birch (Betula spp.), and ash (Fraxinus spp.) were species much less represented but, well worth including for the diversity they brought. Except for Oak Openings, where pines or spruce were planted in small groups during the Great Depression by the Civilian Conservation

Corps, evergreens were seldom seen at the majority of collection sites. Woody shrubs were widely varied at each site. Some that were represented were hackberry (Celtis spp.), viburnum

(Viburnum spp.) witch-hazel (Hamamelis virginiana), rose (Rosaceae), including others. The number of arthropods collected from each tree or shrub sampled are listed in Table13 and Figure

14.

A large variety of low-growing vegetation blanketed the forest floors; no arthropods were collected from this vegetation, in the soil or on top of the soil, the forest canopy, or inside the trees themselves, where tunneling insects and insect larvae live. We used the beat-stick method for collecting arthropods; we chose to limit our collecting to a specific area in every forest site.

Collections were made from; 0.3m. to 2.5m. from the soil surface. Only woody shrubs and trees were sampled.

Movement through each forest site was a random walk and the beat-stick method of sampling was used. This method of collection concentrated on free moving arthropods on twigs, leaves, and branches of shrubs and trees. Time allotted for collection purposes was kept between 40 and 45 minutes. Approximately half the collection time, about 20 minutes, was used along forest edges or edges of paths within the forest. The other half of the collection time was spent a minimum distance of 14 meters from paths or edges of the forest and into areas of little or no disturbance within the forest. The beat-stick method equipment consisted of a cut broomstick approximately 1/2 m. in length, and a large plastic storage box lid measuring 46 cm. by 61 cm. and 2 cm. deep. A white storage box lid was chosen so that arthropods that dropped 9 from the branches could be easily seen. The lid was held under a branch and several firm hits on the branches with the broomstick jarred the arthropods loose and they fell onto the lid. The lid was then held at an angle, and the arthropods were then slid into the large plastic freezer bags along with a sample of that particular plant. A list of the thirteen orders of arthropods collected along with the common names and some descriptive terms can be seen on (Table 2). Collecting was always done on days that were clear and dry and with a minimum temperature of 70 degrees.

Statistical Analyses

Species richness and the Shannon Weiner (H’) index of species diversity (Magurran, 1988) were used as indicators of arthropod species diversity in each of the nine forest areas, see (Table

9) for individual site collection data. In environmental monitoring, estimates of species richness are used frequently (Lovejoy, 1994). Sorensen’s Similarity Index is regarded as one the most effective presence / absence similarity measures (Magurran, 2004), see (Table 5). Sorensen’s was used to approximate the amount of similarity between the study sites. Analysis of variance

(ANOVA) was used to determine if any significant differences occurred among the nine forest sites in terms of number of Orthoptera, Arachnida, Coleoptera, and Hemoptera species. We also looked at arthropod orders and selected the ten most often collected of these, in large and small

forests and calculated these separately for mean species richness, standard deviation, standard

error of the mean, p-value and t-value shown in (Table 12). In (Figure 4), lettered (A-J), are bar

graphs, each illustrating the arthropod order collected over the 2005 and 2006 collection seasons,

we then plotted the number of individuals captured at each of our nine sites. Graphs were

completed comparing arthropod abundance to tree species numbers and a second graph using the 10 number of species to number of tree species, (Figures 6 and 7). (Table13) lists each tree species that was collected from at each site and the number of arthropod species found on that tree or shrub species. A pie chart, see (Figure1) illustrating the percent of total arthropods collected for the two seasons and separated by order. Individual bar graphs constructed per order of arthropod, showing the number of arthropods from that order which occupied each site can be seen on (Figure 4, A-J). Arthropod abundance, species richness, Shannon diversity, and

Shannon Evenness were compared between small and large forests using two-sample t-tests. An alpha level of 0.05 was used for all statistical analyses.

11 RESULTS

During 2005 and 2006, a total of 768 arthropods were collected in the nine forested sites.

Fifty separate tree or shrub species in twenty different families were collected from, and identified for each forested site (Table 1). The diversity of flora is of value as it creates critical habitat, food resources, nesting sites, and refuges for forest dwelling species. Table 13 documents the total arthropods collected, in addition, a cumulative species list of thirteen different orders of arthropods were documented in (Table 14). The collection was dominated by the order Coleoptera (beetles), at 41% of the collection and 287 total specimens (Figure 3 and

Table 2). This is somewhat higher than expected since it is estimated that 33% or 1/3 of all insect species worldwide are of the order Coleoptera. Spiders and Phalangids (daddy long-legs) of the orders Araneae and Opiliones, which throughout this report were grouped together as

Arachnids, the class Arachnida, all predatory, accounted for 21% of the total collection with 150 individuals. The Arachnida collected numbered approximately half that of Coleoptera, however, those of the class Arachnida were the second most frequently captured arthropod in this study.

Hemiptera occurred at nearly the same frequency as Araneae and Opiliones, with 16% occurrence of the 115 specimens collected. A large drop in collection frequency was observed with the following three orders: Orthoptera with 52 individuals and only 7% of the total. The p- value of Orthoptera was the single significant figure with 0.031 as seen on (Table 12).

Hymenoptera had 45 specimens and 6% of the total, and Diptera included 33 specimens and accounted for 5% of the collection. Insects rarely seen or collected included the orders

Neuroptera, Dermaptera, and Psocoptera, each with only 1% of the total, and included eight specimens each of these three orders. The orders Lepidoptera, Ephemoroptera and Trichoptera 12 combined accounted for 1% of the 768 specimen collection. Lepidoptera was represented by

three specimens, while Ephemoroptera and Trichoptera were represented by two specimens each.

A total of 212 species were collected in the small forests, with a total abundance of 468

individuals. In large forested sites 146 species were obtained and had a total abundance of 300 individuals. The bar graphs for each order illustrate the relative number of arthropods per site

(Figure 4), many of these sites showed high variability from site to site, while others showed similarities to one and other, for the number of arthropods captured.

The mean total arthropod abundance for small forests was 93.6, while for large forests it was

75.0. The small forests had a mean species richness of 42.4, large forests were 36.5. Small forests and large forests had similar mean Shannon Index (H’) as see on (Table 4), all sites ranged between 1.22 and 1.67. Individual collection dates as with (Table 6), Shannon Index numbers varied from 0.65 to 1.35 and Evenness ranged from 0.42 to 1.00. A similar table with collective results for each forest, (Table 7), Shannon Index ranged from 1.22 to 1.65 and

Evenness per forest ranged from 0.03 to 0.91.

The arthropod communities of Pearson Park and Oak Openings were the least similar to each other, with a Sorensen’s Index of 0.41. The same index value of 0.41 was found in two other site comparisons; Pearson Park to Bradner Preserve and Secor Woods to Pearson Park. Sites that were the most similar were Bradner and Fuller with 0.56. The highest similarity score and the lowest score showed little difference between them. Overall, the nine sites showed moderately low similarity among them.

Two-sample t-tests were performed on the biodiversity indices for large and small forests

(Tables 8-11). The p-values for total species, total arthropods, Evenness, Shannon Index are p- value of 0.24, p-value of 0.298, p-value of 0.468, and p-value 0.653, respectively. None of these 13 numbers were significant, but the means of the t-tests performed was larger for small forests. No significant numbers were found where linear regressions considering species richness and woodlot size in hectares occurred.

Total species to total number of hectares, (Figure 5) result shows a reduction in total species as hectares increase. Total tree species were compared to total arthropod abundance, (Figure 6) which shows an expected increase of arthropod abundance as tree species numbers increase.

Total tree species vs. total arthropod species, (Figure 7) shows an expected increase of arthropod species as the number of tree species increase.

Analysis of variance (ANOVA) for Orthoptera, Arachnida, Coleoptera and Hemiptera species showed no significant differences were found. For any of the fore mentioned groups

(ANOVA p> 0.05). However, ANOVA of the numbers of Hemiptera present in the nine forests was significant (F=3.97, DF= 8, 27, P=.003). A Tukey-Kramer mean separation procedure indicated that Baldwin had a significantly greater number of Hemiptera species than did Carter and Oak Openings (P=0.05) and Pearson had a significantly greater number of Hemiptera species than did Oak Openings (p=0.05).

14 DISCUSSION

A species responds in different ways to a forest site depending upon its capabilities for

dispersal, home range, quantity of food sources, and climatic trends. Fragmentation, a human

induced phenomenon, continues to change our landscapes on a grand scale. Fragmentation

effects the amount of habitat availability, forces isolation of species, reduces availability of food

and nesting sites, increases edge area dramatically and causes drastic edge effect increases.

Conservation biologists know that the small forests will usually have different habitat types than

large areas and different habitats support different communities in most cases (Rosenzweig

1995). For many the reduction in size of habitat is correlated with changes in soil conditions, for

example, an increase in fertility and a decreasing humidity could result from anthropogenic

fertilization and drainage in an adjacent area. This condition would then translate into plant

growth changes. Where plant monocultures exist, resource quality of the arthropod community

may change with the stand size. Smaller stands of plant material can produce larger leaf fronds

and shoots, while large stands produce significantly smaller fronds and shoots (Rigby and

Lawton 1981; Tscharntke 1992). Changes in plant growth could potentially affect arthropod

communities that interact with that species or group of plants. For arthropods that feed on these

changed plants, they could, for example, offer more or less plant material as a food source. An

increase or decrease in arthropod species availability would eventually affect other arthropod populations that feed on those arthropods from the changed population, and so on.

Small islands, in contrast, often have much higher productivity per unit area than large

islands and can lead to higher population densities and lower extinction rates, in general

(Andersen and Wait 2001). It is important to remember that the effects of fragment size can be

clouded by changes in food quantity and complexity, because resource biomass is often more 15 important than resource heterogeneity in determining insect diversity (Waide et al. 1999;

Koricheva et al. 2000). Smaller forests typically have increased sunlight penetration. Smaller forests offer fewer resources to predators, such as birds, though varying per species, tend to need many times more forest habitat then most arthropod species. A reduction in avian predators because of the reduction of nesting space and availability of mates could affect arthropod populations.

Arthropod abundance with my study showed a higher number of individuals were collected from small forests than from larger forests. Approximately half of my allotted time collecting was spent in the interior of the site, while half of my time was spent at the outside edges of the forests. Typically, larger numbers of arthropods were collected on the edges than within the interior. This was especially evident on very sunny days. One could stand at the outside edge of the site and observe the huge amount of activity on the outer leaves and twigs. This flurry of

activity was never witnessed at the interior of the forest or on shaded areas at the edge of the

forest. An explanation for the higher numbers at smaller woodlots maybe that continuous

fragmentation of land areas has created an increase in the total edge area, as we cut forest areas

into smaller and smaller pieces we may be seeing a larger edge at the smaller sites making them

predominantly edge area with little or no interior. Therefore, the edge species, many of which

are highly mobile, and prefer sunlit habitats, occupy more than the outer most edge of the forest,

can occupy possiblely dozens of meters into the apparent interior. In the case of small forests, a

site could be all or nearly all edge. These edge arthropods could also be transient or migratory

species, simply moving through from the surrounding matrix of mostly agricultural fields.

Migratory status is often the most significant life history predictor of the patch area effect.

Many migrant species are thought to be more area sensitive, whereas resident species are said to 16 be more “tolerant” of fragmentation effects because of differences in life history traits. For example, residents are reported to exhibit differences in nest-building behaviors that make them less susceptible to predators (Weins 1989b, Hansen and Urban 1992, Bohning-Gaeseet al. 1993).

It was found in one study that patch size effects were contingent upon both migratory status and habitat association. This suggests a more complex system than what has been previously reported. Therefore, as habitat losses occur and habitat patches are reduced in area, patch size effects should produce a greater decline for resident interior species (Connor et al. 2000).

Population density may remain constant across island size as predicted by the traditional equilibrium theory, but may also be smaller or larger than expected from habitat area alone

(Connor et al. 2000). In a study on butterflies and fragmentation, species specialists were reduced on small fragments and butterfly species generalists increased densities due to the contribution of the surrounding landscape matrix (Steffan-Dewenter and Tscharntske 2000).

Generalist species regularly showed a mean patch size effect that was very close to zero, regardless of the life history of the landscape (Bender et al.1998). Habitat specialists are more susceptible to extinctions than generalists (With and Crist 1995; Zabel and Tschatncke 1998;

Steffan Dewenter and Tscharntcke 2000). With specialized herbivores, or monophagous species, the landscape produces a pattern of isolated habitat islands, where as with polyphagous species these same islands may be connected by further usable habitat patches, thereby producing a habitat continuum. It is less likely on small forest patches, for a species to have different parts to a habitat with a blend of resources. For example, bees need both suitable nesting sites and pollen plants (Gathmann et al. 1994; Tscharntke et al. 1998). Parasitoids depend on a spatially and temporally co-occurrence of hosts and nectar (Russell 1989). Many monophagous insect 17 herbivores may spend their whole life on one host plant, feeding, copulating and ovipositing

(Zwolfer and Harris 1971; Tscharntke 1999).

Most organisms do not live completely independently of others organisms, but depend on more or less intimate interactions with other species (Redfearn and Pimm 1987). Availability of mutualists may be reduced in small, isolated habitats due to the limited size of a fragment which would restrict variability within the animal and plant communities. Variability would be limited to the number and type of species that occupy and could be supported by the fragment, new breeding individuals within a species would rarely be available because the plot would only be able to support a limited number of individuals. Where new-comers were available this would be a “by-chance meeting” between the occasional visitor and the resident occupant. Diversity would be predominantly limited to the species that were present at the time the fragment was cut, as there would be few new species introduced who would become residents, due to isolation.

Isolation would restrict immigration and emigration to the fragment, because of the matrix forms a sort of barrier around the patch. Species depending on pollinators, fungi or seed dispersers should be affected to a higher degree than non-dependent species.

Isolated patches of flowering plants receive fewer visits from pollinators, leading to reduced seed production (Jennersten 1988; Steffan-Dewenter and Tscharntke 1999). Where plant populations were similarly effected by isolation, many species were found for species with a low seed production and low dispersal capacity (Grashof-Bokdam 1997, Dupré and Ehrlén 2002).

These species therefore, may not be able to successfully bridge the intensively used agricultural matrix to colonize new forest patches. Recently, Verheyen et al. (2003), provided evidence that low dispersability is a major constraint for recovery of forest plants following land cultivation.

Experimental introductions of forest species into unoccupied sited and analyses of colonization 18 patterns further support the idea that many forest species are limited by dispersal (Matlack 1994,

Fröborg and Erikson 1997, Brunet and von Oheimb 1998).

Communities of small isolated habitats or islands are typically dominated by species with high dispersal capabilities (Bunce and Howard 1990; den Boer 1990; de Vries et al. 1996;

Thomas 2000). Many species have to travel between patches as critical resources are found in patches of different types (Dunning et al. 1992).

Information on movement rates of organisms in fragmented landscapes are critical for predicting extinction thresholds, but little is known of the dispersal ability of most insect or arthropod groups (Fahrig 2001). Insects differ from vertebrates as they have small home ranges and fewer dispersal capabilities. Because of this, they are more affected by isolation barriers, but can cope better with small habitat fragments (Tscharntke et al. 2002). That is, except for flighted insects, which in general have a more difficult time dispersing any great distance because of the time and energy output it takes them to move over a relatively small distance. In patches with no connectivity or where the patches are a fair distance apart, creating an island or barrier effect, many species will not attempt to enter or cross a radical and abrupt change of habitat.

Vertebrates are typically able to cover much greater distances in a shorter period of time.

The area around habitat fragments may offer only suboptimal resources, but it may still serve as a foraging area, thereby, enhancing the fragments’ population (Zschokke et al. 2000;

Fahrig 2001). In this study collection sites there were, in most cases, two or more forest sides surrounded by farm land, which encouraged foraging and increased sunlight access to the forest edge areas. In a study of the role of regional effects on butterfly communities in Sweden, landscape structure was more important for butterfly diversity than the local farming system

(Weibull et al. 2000). 19 Communities are composed of species that experience the landscape on a broad range of spatial scales (Holt 1996; Debinsky and 2000). While some landscape features such as scale are in small sectors this will encourage the species affected by much larger sectors (Roland and

Taylor 1995, 1997). The relative importance of local habitat quality for the strength of biotic interactions may decrease with increasing complexity of the surrounding landscape (Thies and

Tschartke 1999; Östman et al. 2001).

Small-scale fragmentation can lead to an increased density of herbivores and experimental grassland fragmentation which can alter aphid population dynamics (Braschler B. et al. 2003).

In a fragmentation experiment, lady bird beetles were a late arrival to the 1m² plots with 1m² between each plot. The small amount of isolation and discontinuity in favorable habitat appear to affect the movement and foraging pattern in these mobile organisms (Kareiva 1984, 1987). In another study by Roland Taylor (1995, 1997), forest fragmentation affected parasitoid survival and tent caterpillar outbreaks. The spatial scale at which forest structure had the greatest effect differed among parasitoid species depending on the parasitoids’ body size. In general, the abundance and distribution of species with large home ranges or high trophic levels should depend on larger spatial scales than species with very small home ranges or low trophic levels and differences such as these may affect community structure and interactions (Holt 1996).

It is difficult to say just how much of the effect of edge area is attributed to the geometric effect alone. The geometric effect states that the most successful species preempts the most space; the next successful species occupies the next largest share of space and so on, until little space is left. The degree of effect would depend on patch size, but there will always be a relationship between density and patch size for edge and interior species. This effect has been reported by numerous studies (Whitcomb et al. 1981, Lynch and Whigham 1984, Merriam and 20 Wegner 1992, Johns 1993, McGarigal and McComb 1995). Geometric effect would not be the

only pressure affecting these fragmented systems. Edge and interior species are more prone to

patch size effect due to other factors.

When looking at the distance of a boundary for any species, it is difficult to define. There is

no distinct threshold beyond which the distribution of an animal abruptly begins or ends. Such

boundary distances are most certainly site specific, as they are determined by local conditions

such as, microclimate, vegetation composition, and the presence or absence of ecological enemies. Therefore, boundary distance estimates may only be relevant to a study species and

may only be of temporary relevance, and because of the mobility of animals, their populations

may fluctuate or shift geographically over time. The findings could not be extrapolated to other

populations within a species.

The observation in this study concluding that interior sites had significantly different faunal

assemblages from the outside edges suggests that habitat fragmentation has a measurable

influence on the community of arboreal insects. Interior sites are least vulnerable to

fragmentation processes, as they were surrounded and protected by edge (Majer 2001). Interior sites tended to have fewer species and fewer arthropods than the edges. This could have been due to the increase of sunlight at the edges warming insects and encouraging flower bloom.

Fauna at the edges may have played a part in the increase of insects at the edges, from the increased sunlight which may be influencing additional plant growth, sun-loving species that would not survive in a shady forested interior landscape. The forest forms a sort of wall at the outside edge where wind dispersed seeds from the surrounding matrix of ditches and roadside vegetation could be stopped by trees and ground vegetation, thereby, taking root at the floor of the forests’ edge where sunlight is plentiful. Also, shrubs could inadvertently scrape seeds from 21 an animals’ fur thereby, dropping in an area with adequate sun and moisture. This increase of

vegetation offers a variety of hiding, nesting, and food resources to resident, as well as transient

and migratory species. Over time, edge-induced changes in light and forest microclimate may

decline as older edges become “sealed” by a profusion of new leaf growth Williams-Linera

1990, Matlack 1994, Kapos et al. 1997). Fragmentation causes a pronounced acceleration of

tree-community dynamics in Amazonian rain forests. The most important proximate cause of

elevated tree mortality, damage and turnover in fragments is probably edge effects, particularly

changes in microclimate and greater wind turbulence near edges. Condition changes including

hotter, drier forest areas penetrating at least 40-60 meters into fragment interiors. Numerous

dead trees standing near new edges (Lovejoy et al. 1986, Ferreira and Laurance 1997) may have been killed by sudden change in wind, temperature, relative humidity, or soil moisture, which exceeded their physiological tolerances. Observations from two studies recorded dramatically increased leaf fall near recently created edges (Lovejoy et al. 1986, Sizer 1992). This would suggest affected trees suffered from severe water stress or shed shade-adapted subcanapy leaves, which were suddenly exposed to direct sunlight near edges.

Winds striking an abrupt forest edge can cause increased turbulence, leading to increased windthrow and forest structural damage (Laurence 1991, 1997, Chen et al. 1992). Area effects that could influence tree species persistence in fragments include population-level processes, such as the collapse of small populations via random genetic or demographic events (Schafer

1981), and community-level phenomena, such as declines in reproduction following losses of specialized pollinators or seed dispensers (Powell and Powell 1987, Aizen and Feinsinger 1994).

Because of elevated tree mortality and damage near edges, forest fragments will tend to have high proportions of their area in gap. These effects will be greatest in small, irregularly shaped 22 fragments, which have the highest ratio of edge to area. Based on the half-lives of tree

communities, (time for 50% of all measured stems to die) trees would be only 9.8 years for 1-ha fragments and 28-32 years for larger (10-100 ha) fragments, compared to 54 years for forest

interiors. Substantially elevated rates of gap formation will alter the structure, floristic

composition and microclimate of forest remnants (Clark 1990, Denslow 1995, Kapos et al.

1997).

Wet, rainy environments tended to encourage the arthropods to seek cover and this caused the

number of specimens collected to drop dramatically. This was realized in mid spring of the first collection year in 2005. During this time, the temperature was 64 degrees and the foliage was wet. No arthropods were collected the first day and the second day only one ant was captured. It was decided to wait until the temperatures were 70 degrees or warmer and the foliage was drier.

This correlates to the fact that arthropods, being ectotherms, need the warmer environmental temperatures in order to move and digest food. A cumulative species list for each forest was compiled, divided by orders and containing the number of species, the total of species per site and the number of arthropods per site (Table 14).

The results of this study and others suggest that fragmentation may actually have a tendency to increase densities of herbivorous edge species. It is possible that herbivore densities may be more closely linked to food production within the edge habitat. It has been shown that the diversity and productivity of edge plant species is greater in small than in large patches

(Levenson 1981). For interior species, the decline in population size associated with habitat fragmentation per se will be greater than that predicted from pure habitat loss alone. The ratio of

interior habitat to total patch size declines as patches become smaller following fragmentation and loss. For edge species, the decline in population size will be less than that predicted by pure 23 habitat loss alone. Relative abundances of edge species may actually increase in the landscape following fragmentation, especially when fragmentation serves to increase the total amount of edge habitat for these species, our collection site totals suggest this very phenomenon. Patch size effects are not expected to be dependent upon the amount of habitat cover that is present in the landscape. However, if the only pattern of loss is removal of mostly small patches, pure habitat loss will have a greater effect on edge species than on interior species. Likewise, if only large patches are removed, habitat loss will have a greater effect on interior species. Resident interior species show the largest patch size effects, indicating that this group should suffer the greatest decline associated with habitat fragmentation. Generalist species are not associated with only the edge or only the interior habitat. The decline in population size associated with habitat destruction should be accounted for by pure habitat loss alone. Patch size effects are not expected to be an important factor in determining the population size of generalist species fragmented landscapes (Bender et al.1998).

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32 Table 1: Trees and woody shrub species found in the nine collection sites grouped and into families, including scientific and common names.

MAPLES (Acereae)

Acer negundo Boxelder tree Acer rubrum Red maple Acer saccharinum Silver maple Acer saccharimae Sugar maple

DOGWOODS (Cornaceae)

Cornus alternifolia Alternate-leaf dogwood Cornus florida Flowering dogwood Cornus frommondii Roughleaf dogwood

HICKORY (Juglandaceae)

Carya ovata Shagbark hickory Carya laciniosa Shellbark hickory

BIRCH (Betulaceae)

Carpinus caroliniana Ironwood Corylus americana Hazel nut

ELM (Ulmaceae)

Celtic occidentalis Hackberry Ulmus americana American elm Ulmus rubra Slippery elm

MADDER (Rubiaceae)

Cephalanthus occidentalis Buttonbush

LEGUME (Leguminosae)

Cercis canadensis Eastern redbud Gleditsia triacanthos Honey locust Robinia pseudoacacia Black locust

33 (cont.)

RUE (Citrus) (Rutaceae)

Zanthoxylum americanum Northern prickly ash

ROSE (Rosaceae)

Crataegus cru-galli Cockspur hawthorne Crataegus flabellate Fanleaf hawthorne Malus cornaria Sweet crabapple Malus sylvestris Apple tree Prunus avium Sweet cherry Prunus cerasus Sour cherry Prunus serotina Black cherry Prunus virginiana Choke cherry

BEECH (Betulaceae)

Fagus grandiflora American beech Quercus alba White oak Quercus bicolor Swamp oak Quercus coccinea Scarlet oak Quercus ellipsoidalis Northern pin oak Quercus rubra Northern red oak Quercus velutina Eastern Black oak

OLIVE (Oleaceae)

Fraxinus americana White ash

WITCH-HAZEL (Hamamelidaceae)

Hamamelis virginiana Witch-hazel

MAGNOLIA (Magnoliaceae)

Liniodendron tulipifera Tulip tree

MULBERRY (Moraceae)

Morus alba White mulberry

34 (cont.)

WILLOW (Salicaceae)

Populus tremuloides Quaking aspen Salix bebbiana Bebb willow

CASHEW (Anacardiaceae)

Rhus glabra Smooth sumac Rhus typhina Staghorn sumac

BUCKTHORN (Rhamnaceae)

Rhamnus cathartica European buckthorn Rhamnus frangula Glossy buckthorn

LAUREL (Lauraceae)

Sassafras albidum Sassafras Lindera benzoin Northern spicebush

HONEYSUCKLE (Caprifoliaceae)

Sambucus canadensis Elderberry Viburum opulus European snowball

BASSWOOD (Tiliaceae)

Tilia Americana American basswood

35 Table 2: Orders of arthropods collected from the nine forest sites including the scientific name by order and the common name with descriptive terms.

ORDER COMMON NAME

Araneae Spiders, ticks, mites (eight legs)

Coleoptera Beetles Ex.stag beetles, lightening bugs, flea beetles, lady bugs/beetles, weevils (including soft-bodied and ant-like beetles) Dermoptera Earwigs (w/ two long, curved cerci)

Diptera True flies (two-winged)

Ephemoroptera Mayflies

Hemiptera True bugs (w/peircing sucking mouth parts) Ex. Stink bugs, assassin bugs, water striders, cicadas, aphids scale insects

Hymenoptera Ants, bees, wasps, sawflies

Lepidoptera Moths and butterflies

Neuroptera Lacewings, antlions, fishflies and relatives (nerve-winged insects) Opiliones Daddy long-legs, harvestman (eight thread-like legs)

Orthoptera Crickets, katydids, grasshoppers

Psocoptera Booklice, barklice (not true lice)

Trichoptera Caddisflies 36 Table 3: Description of forest site fragments and number of times collected from.

OHIO AREA # TIMES COLLECTED WOODLOT COUNTY (ha) (ac) in TWO SEASONS

Oak Openings Lucus 1514.77 3743.0 4

Secor Woods Lucus 222.58 550.0 4

Bradner Preserve Wood 92.27 228.0 4

Fuller Preserve Wood 3.24 8.0 4

Baldwin Preserve Wood 53.0 130.96 4

Steidtman Woods Wood 26.7 65.98 4

Pearson Park Lucus 128.3 317.03 4

Carter Woods Wood 2.0 4.94 4

BGSU Environmental Wood 1.6 3.95 4 Woodlot 37 Table 4: Summary of diversity indices for forest fragments collected from, in the summers of 2005 and 2006 in northwest Ohio.

WOODLOT PATCH SIZE (ha) SHANNON EVENNESS (E) (rounded to nearest INDEX (H’) hectare)

Baldwin Woods 53.0 1.443248 0.883548

Bradner Preserve 92.2 1.35729 0.901764

Carter Woods 2.0 1.355362 0.829048

Environmental 1.6 1.390687 0.908068 Woodlot

Fuller Preserve 3.2 1.668323 0.946068

Oak Openings 1514.8 1.223094 0.8642978

Pearson Park 128.3 1.649591 0.975976

Secor Woods 222.6 1.468925 0.967344

Steidtman Woods 26.7 1.502975 0.80156

Table 5: A summary chart w/Sorensen's Similarity Index for arthropod communities collected from the nine fragmented forests sites in Lucus and Wood County in northwest Ohio.

WOODLOT Fuller Bradner Secor Pearson ENV. Steidtman Carter Baldwin

Oak Openings 0.43 0.5 0.5 0.41 0.48 0.46 0.46 0.46

Fuller 0.56 0.55 0.49 0.54 0.53 0.53 0.52

Bradner 0.5 0.41 0.48 0.46 0.46 0.46

Secor 0.41 0.49 0.47 0.47 0.46

Pearson 0.55 0.54 0.54 0.54

ENV. 0.48 0.48 0.48

Steidtman 0.45 0.49

Carter 0.49 38 39 Table 6: Individual collection site calculations for each date collecting took place.

SITE DATE SPECIES ABUNDUNCE SHANNON EVENNESS baldwin woods 15-Aug-05 10 11 0.99 0.99 baldwin woods #1 27-Aug-05 13 24 1.19 0.93 baldwin woods #2 27-Aug-05 19 38 1.19 0.93 baldwin woods 30-Jun-06 20 41 1.09 0.84 bradner preserve 7-Sep-06 15 17 1.16 0.99 bradner preserve 9-Aug-06 11 15 1.00 0.85 bradner preserve 26-Jun-06 8 14 0.79 0.88 bradner preserve 5-Aug-05 8 18 0.82 0.90 carter woods 6-Jul-05 16 60 0.94 0.53 carter woods 28-Aug-05 13 18 1.08 0.83 carter woods #1 16-Jun-06 12 15 1.04 0.88 carter woods #2 16-Jun-06 12 18 0.88 0.81 environmental wood lot #1 16-Jun-06 10 19 0.87 0.68 environmental wood lot #2 16-Jun-06 10 14 0.96 0.84 environmental wood lot 30-Jun-06 15 27 1.04 0.73 environmental wood lot 7-Sep-06 12 21 1.02 0.77 fuller preserve 22-Jun-05 27 50 1.34 0.94 fuller preserve #1 24-may-06 18 21 1.24 0.98 fuller preserve #2 24-may-06 16 25 1.11 0.92 fuller preserve 10-Sep-06 8 14 0.81 0.71 oak openings 24-Jun-05 9 20 0.78 0.82 oak openings 1-Jul-05 9 35 0.65 0.42 oak openings #1 8-jun-06 13 16 0.99 0.82 oak openings #2 8-jun-06 7 12 0.86 0.80 pearson 23-May-06 19 25 1.22 0.95 pearson #1 6-jul-06 27 42 1.35 0.94 pearson #2 6-jul-06 17 41 1.04 0.84 pearson 8-Aug-06 10 10 1.22 0.95 secor woods 20-Jul-05 9 12 0.93 0.86 secor woods #1 6-jul-06 12 12 1.03 0.95 secor woods #2 6-jul-06 10 10 1.00 1.00 secor woods 25-Jul-06 6 9 0.69 0.72 steidtman woods #1 10-may-06 12 18 0.99 0.79 steidtman woods #2 10-may-06 12 13 1.07 0.96 steidtman woods #1 25-aug-06 15 24 0.88 0.64 steidtman woods #2 25-aug-06 14 16 1.04 0.86

In the "date" column where a #1 or #2 is noted, this indicates two people were collecting on the same site and the same date, but in different areas of that forest. Table 7: Summary chart of total and combined data for each of the nine forest sites.

TOTAL TOTAL SITE AREA IN HA SPECIES ARTHROPODS SHANNON EVENNESS

Pearson Park 128.3 49 115 1.64959 0.033665

Baldwin Woods 53 43 110 1.443248 0.883548

Bradner Preserve 92.2 32 65 1.35729 0.901764

Fuller Woods 3.2 57 109 1.668323 0.9466068

Secor Woods 222.6 33 44 1.468925 0.967344

Carter Woods 2 37 105 1.355362 0.036631

Steidtman Woods 26.7 41 75 1.502975 0.80156

Oak Openings 1514.8 32 76 1.223094 0.038995

Environmental 1.6 34 69 1.390687 0.908068 Wood Lot 40 41 Table 8: Two-Sample T-Test for Shannon in Small vs Large Forests.

Mean Stand. Dev. Stand. Error T-Value P-Value Mean Group 1 (Small Forests) 1.472 0.123 0.055 Group 2 (Large Forests) 1.425 0.18 0.09 0.47 0.653

Table 9: Two-Sample T-Test for Evenness in Small vs Large Forests.

Mean Stand. Dev. Stand. Error T-Value P-Value Mean Group 1 (Small Forests) 0.715 0.383 0.17 Group 2 (Large Forests) 0.485 0.519 0.26 0.77 0.468

Table 10: Two-Sample T-Test for Total Species of Small vs Large Forests.

Mean Stand. Dev. Stand. Error T-Value P-Value Mean Group 1 (Small Forests) 43.8 7.05 3.2 Group 2 (Large Forests) 36.3 10.6 5.3 1.28 0.24

Table 11: Two-Sample T-Test for Total Arthropods of Small vs Large Forests.

Mean Stand. Dev. Stand. Error T-Value P-Value Mean Group 1 (Small Forests) 93.6 19.9 8.9 Group 2 (Large Forests) 75 29.8 15 1.13 0.298 42 Table 12: Forested habitat was separated into large or small sites per each order. Below shows mean species richness, standard deviation, standard error mean, P-value,and T-value. * shows significance

Arthropod Order Forested Habitat Mean Species Stand. Div. S. E. Mean P-Value T-Value Richness

Coleoptera small 14.25 1.89 0.95 large 11.4 3.29 1.5 0.154 1.53

Neuroptera small 0.6 0.894 0.4 large 0.4 0.894 0.4 0.733 0.35

Hymenoptera small 4 2.55 1.1 large 3 2.45 1.2 0.571 0.59

Diptera small 2.2 1.1 0.49 large 2 0.816 0.41 0.771 0.3

Lepidoptera small 0.6 0.548 0.24 large 0.5 0.577 0.29 0.798 0.27

Hemiptera small 8 4.3 1.9 large 5.75 4.03 2 0.449 0.8

Orthoptera small 3.4 1.34 0.6 large 1.25 0.957 0.48 0.031* 2.69

Dermoptera small 0.4 0.548 0.24 large 0.25 0.5 0.25 0.685 0.42

Arachnida- (Araneae& small 11.25 4.32 1.9 Opiliones) large 10.75 4.27 2.1 0.88 0.16 43 Table 13: Cumulative tree and woody shrub species per site including the total number of arthropod species found on each of these plant species.

OAK OPENINGS

Tree and Shrub Total Arthropod Genus /Species Species

Acer rubrum. ……………………...... 8 Acer saccharinum …….……………....3 Corylus Americana …….…….……….5 Hamamelis virginiana ….…….……..12 Prunus avium. ………….………….....3 Quercus valutina….….…………...... 1 Rhamnus cathartica………...…………1 Salix bebbiana………….…..……….....1 Ulmus americana…………….…..……3 Ulmus rubra…………..……………...11

FULLER PRESERVE

Tree and Shrub Total Arthropod Genus /Species Species

Acer rubrum………………….…….…4 Acer saccharinum……………….….....3 Carya laciniosa……………….……....9 Cornus frummondii…………….……..2 Lindera benzoin………………….……4 Quercus alba……………………...... 9 Quercus bicolor………………….…....4 Rhamnus cathartica……………….....12 Rhamnus frangula…………………..….7 Tilia americana………..…………..…..8

44 (cont.)

PEARSON PRESERVE

Tree and Shrub Total Arthropod Genus /Species Species

Acer saccharum……………………....2 Acer saccharinum…………………….9 Carya ovata………………………...... 3 Carpinus caroliniana………………...13 Cephelanthus occidetalis……………...5 Cercis canadensis…………………...... 1 Cornus frummondii…………………..15 Crataegus crus-galli…………………..1 Hamamelis virginiana………………..12 Prunus serotina………………………..2 Rhamnus cathartica………………….15 Sassafras albidum……………………..1 Tilia americana………………………..5 Ulmus rubra…………………………...1

ENVIRONMENTAL WOODLOT

Tree and Shrub Total Arthropod Genus /Species Species

Acer negundo………………………….7 Cornus frummondii……………………2 Fraxinus americana…...……………....2 Malus coronaria ...... 2 Morus alba……………………………..4 Quercus bicolor ……………………....21 Rhus typhina.. ………………………….3 Salix bebbiana………………………….2 Ulmus rubra…………………………....8

(cont.)

CARTER WOODS