Insects

The following is a guide to some of the insects that may be encountered in the Arboretum.

1. Family
2. Habitat: where it can be found in southern Minnesota
3. Most commonly heard vocalizations (if applicable)
4. Size
5. Status at Gustavus (when and how often it is seen on campus)
6. Additional information

Butterflies and Moths

Monarch (Danaus plexippus)

• Status: commonly seen in prairies and gardens of Arb and rest of campus mid-May to early October
• Habitat: prairies and grasslands, especially where milkweed (host plant) is plentiful
• Wingspan up to 4 inches
• State Butterfly of Minnesota

Viceroy (Limenitis archippus)

• Status: infrequently seen in prairies and gardens of Arb and rest of campus late May to early October
• Habitat: open areas near willows and poplars (host plants)
• Wingspan up to 3 inches
• Mimics the monarch in appearance; while the monarch is poisonous to predators, the viceroy is not

Red-spotted Purple (Limenitis arthemis)

• Status: very rarely seen in gardens of Arb, only observations from late July 2010 and early August 2011
• Habitat: open woodlands and forest edges, especially near birches, willows, and poplars (host plants)
• Wingspan up to 3 inches
• Now considered the same species as the White Admiral, which is a butterfly more common in northern Minnesota

Eastern Tiger Swallowtail (Papilio glaucus) L.

• Status: infrequently seen in gardens and wooded areas of Arb and rest of campus mid-May to late September
• Habitat: semi-open to dense woodlands, open areas near trees, especially where poplars (host plants) are present
• Wingspan up to 5 inches
• Males are yellow, but females can be either yellow morph or dark morph

Eastern Black Swallowtail (Papilio polyxenes)

• Status: seen only a few times each year in gardens of Arb from late May to mid-October
• Habitat: grasslands, open areas near gardens, especially where members of the carrot family (host plants) are present
• Wingspan up to 4 inches

Painted Lady (Vanessa cardui) L.

• Status: infrequently seen in prairies and gardens of Arb and rest of campus early May to early October
• Habitat: prairies and grasslands, especially where asters and thistles (host plants) are present
• Wingspan up to 3 inches
• Found on every continent except Antarctica

Red Admiral (Vanessa atalanta) L.

• Status: infrequently seen in gardens of Arb and rest of campus early May to early October
• Habitat: woodlands, wet grasslands, suburban areas where nettles (host plants) are present
• Wingspan up to 3 inches
• Unable to survive cold winters, the northern populations of this species are usually replenished by emigrants from southern populations

Clouded Sulphur (Colias philodice)

• Status: commonly seen in gardens of Arb and rest of campus late May to early October
• Habitat: grasslands, open areas where vetches and clovers (host plants) are present
• Wingspan up to 2 inches
• Males of this species are always yellow while females can appear whitish or light greenish

Cabbage White (Pieris rapae) L.

• Status: commonly seen across campus early May to early October
• Habitat: open woodlands, grasslands, open rural and urban areas where mustards (host plants) are present
• Wingspan up to 2 inches
• Introduced in North America (native to Europe, Africa, and Asia)

Pearl Crescent (Phyciodes tharos)

• Status: commonly seen in prairies and gardens of Arb and rest of campus early May to early October
• Habitat: prairies, pastures, semi-open woodlands, especially where asters (host plants) are present
• Wingspan up to 1 inch

White-lined Sphinx (Hyles lineate)

• Status: infrequently seen in gardens of Arb and rest of campus late May to late September, most often near dusk
• Habitat: wide variety of habitats, gardens
• Wingspan up to 4 inches
• Often mistaken for hummingbirds

Hummingbird Clearwing (Hemaris thysbe)

• Status: very rarely seen in gardens and prairies of Arb, only observations from early August 2009 and late July 2011
• Habitat: wide variety of habitats, gardens
• Wingspan up to 2 inches
• Mimics bumblebees

Dragonflies and Damselflies

Common Green Darner (Anax junius)

• Status: commonly seen in Arb near wetlands mid-April to early October, large numbers seen migrating in May and September
• Habitat: prairies, wetlands, areas near water
• Wingspan up to 4 inches
• One of only two North American insects that truly migrates (other is monarch butterfly)

Meadowhawk (Sympetrum sp.)

• Status: commonly seen in Arb near prairies and wetlands late May to late September
• Habitat: prairies, grassy areas near water
• Wingspan up to 2 inches
• Females and juveniles are golden in color

Twelve-spotted Skimmer (Libellula pulchella)

Photo taken near Grand Marais, Cook County

• Status: commonly seen throughout Arb, especially near prairies and wetlands, late May to late September
• Habitat: prairies, wetlands, grassy areas near water
• Wingspan up to 3 inches

Widow Skimmer (Libellula luctuosa)

• Status: commonly seen throughout Arb, especially near prairies and wetlands, late May to late September
• Habitat: prairies, wetlands, grassy areas near water
• Wingspan up to 3 inches

Cicadas

Annual Cicada (Tibicen canicularis)

• Status: heard daily in Arb and across campus late June to early October, most often around midday, exoskeletons frequently found on tree trunks and wooden structures
• Habitat: woodlands, forested areas, open areas with trees
• Voice is a loud, monotonous buzz lasting up to 10 seconds (made with its abdomen)
• Length up to 2 inches
• Usually begins buzzing once temperature reaches 70°F

Scissors-grinder Cicada (Tibicen auletes)

• Status: infrequently heard in Arb and across campus late June to late September, most often around midday, exoskeletons frequently found on tree trunks and wooden structures
• Habitat: woodlands, forested areas, open areas with trees
• Voice is a loud buzz that alternates up and down in pitch such that it sounds like a saw grinding, lasts up to 5 minutes
• Length up to 2 inches
• Usually begins buzzing once temperature reaches 80°F

Crickets, Grasshoppers, and Katydids

Bush Katydid (Scudderia sp.)

• Status: infrequently seen on plants in Arb and elsewhere across campus, frequently heard at night
• Habitat: gardens, shrubby areas
• Voice is a loud series of short click-like buzzes repeated several times
• Length up to 3 inches
• Similar to grasshoppers in appearance, katydids are more closely related to crickets

Carolina Grasshopper (Dissosteira carolina) L.

• Status: commonly seen in Arb along trails and in open areas
• Habitat: grasslands, open areas, disturbed areas
• Length up to 3 inches
• Cryptically colored at rest, this species reveals dark blue wings outlined in yellow when in flight

Bees and Wasps

Western Honeybee (Apis mellifera) L.

• Status: commonly seen nectaring in gardens of Interpretive Center early May to mid-October
• Habitat: gardens, suburban areas, anywhere near flowers
• Length up to ½ inch
• Originally native to Europe, Asia, and Africa

Bumblebee (Bombus sp.)

• Status: commonly seen nectaring in gardens of Interpretive Center early May to mid-October
• Habitat: gardens, suburban areas, anywhere near flowers
• Length up to ¾ inch
• Both bumblebees and honeybees are important pollinators of crops and wildflowers

Downy Yellowjacket (Vespula flavopilosa)

• Status: infrequently seen in gardens of Interpretive Center early May to early October
• Habitat: gardens, suburban areas, anywhere near flowers
• Length up to ½ inch
• Like all yellowjackets, this species is a classic “picnic pest,” attracted to both sweets and meaty foods

Great Golden Digger Wasp (Sphex ichneumoneus)

• Status: seen in small numbers around gardens of Interpretive Center early May to early October
• Habitat: gardens, suburban areas, anywhere near flowers
• Length up to 2 inches
• A solitary rather than colonial wasp, this species feeds on crickets, grasshoppers, and katydids

Great Black Wasp (Sphex pennsylvanicus)

• Status: commonly seen nectaring in gardens of Interpretive Center early May to mid-October
• Habitat: gardens, suburban areas, anywhere near flowers
• Length up to 2 inches
• While other wasps generally nest up high and in trees, this species nests in holes in the ground

* All photos taken at Gustavus by Bob Dunlap, Arboretum Naturalist unless otherwise noted.