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What do "small," "medium" and "large" numbers mean?
They refer to how many insects were collected per meter square in a 30 second sample. Small means less than 2 insects; medium indicates 2 to 10 insects, and large suggests greater than 10 insects.

home> native plant fact sheets> swamp milkweed

Enhancing Beneficial Insects with Native Plants
Swamp milkweed
 Asclepias incarnata L.

Group: Dicot
Family: Asclepiadaceae (milkweed)
Growth Habit: Forb/herb
Duration: Perennial
U.S. Nativity: Native, most of U.S.

Natural Enemies Attracted: Small numbers of Chalcidoidea, Empididae, Salticidae, Orius insidiosus, Sphecidae, Cynipoidea, Coccinellidae, Chrysopidae and Dolichopodidae.

Pests Attracted: Small numbers of aphids, lygus bugs, leaf beetles, leafhoppers, thrips, Japanese beetles and tephritid fruit flies.

Bees attracted: Moderate numbers (between 1-5 bees per meter square in a 30 second sample) of bees including yellow-faced bees, sweat bees, and large carpenter bees; also highly attractive to honey bees.

Species Notes: Pale and dark pink flower clusters about 3 inches wide open at the top of the plant. Plants filled in well, grew robustly, and grew 3-4 feet tall. Plants bloomed from mid July to mid August. This species was one of the less attractive to natural enemies in the mid season, with the same number of natural enemies as in the grass control.
About the Plant Species Graph: Average number of beneficial insects collected at each plant species the week before, during, and after peak bloom, for plant species blooming from mid-August through early October (+ standard error). Swamp milkweed (Asclepias incarnata) boxed in red. Bars for natural enemies are in green, bars for bees are in yellow. Bars for native plants are solid and nonnative plants are striped. The black line on the top graph shows the number of natural enemies in grass with no flowering plants (grass control). Plants are listed in order of peak bloom. graph
Habitat: Full sun to partial shade and mid-range soil moisture (neither very wet nor very dry). Often found in wet areas such as the edges of rivers and streams, shores, ditches, swales, meadows, wet prairies, and fens. Can also be found in openings in conifer swamps and depressions in woodlands. May be found growing in several inches of water.

Cultivation and Management: Can be easily grown from seed (flowers in second to third year) or plug material (flowers in first year). This plant establishes well from seed and, unlike Common milkweed ( Asclepias syriaca) is not commonly considered an agricultural weed.

Availability: Species is available as seed, plug or container grown material from various native plant nurseries. Michigan Native Plant Producers Association

For more information: USDA-NRCS PLANTS database
This fact sheet prepared by: Doug Landis, Anna Fiedler, Department of Entomology, Michigan State University. Please note: The information presented at this web site should be considered a guideline to be adapted for your situation. MSU makes no warranty about the use of the information presented here. Read disclaimer.
Web site information prepared by: Doug Landis, Anna Fiedler, Rufus Isaacs and Julianna Tuell, Department of Entomology, Michigan State University. Funding support: USDA SARE with Project GREEEN, the Michigan Agricultural Experiment Station, MSU Extension, and the MSU IPM Program.
Web developer: J.N. Landis, MSU IPM Program. Updated: 11/21/06