Fourleaf Milkweed
Asclepias quadrifolia
ID_fourleaf_MW.jpg

Photo Citations

Naturedigger would like to thank the following individuals for their contributions to the fourleaf milkweed (Asclepias quadrifolia) identification slide:

Main flower image provided by: Mark Tomlinson; iNaturalist observation (cropped), CC BY-NC 4.0

Inset flower image provided by: AiWendil; iNaturalist observation (cropped), Public Domain

Leaves, stems and pod images by: Jason Kepska; iNaturalist observation  (cropped), CC BY-NC 4.0

Asclepias quadrifolia Profile

Common Name(s):

fourleaf milkweed

four-leaf milkweed

four-leaved milkweed

whorled milkweed

 

Scientific Name:

Asclepias quadrifolia

 

Native Range United States:
AL, AR, CT, DE, GA, IA, IL, IN, KS, KY,

MA, MD, MN, MO, NC, NH, NJ, NY, OH,

OK, PA, RI, SC, TN, VA, VT, WV

 

Native Range Canada:

ON

 

USDA Symbol:

ASQU

 

Habitat: 

• open, dry or rocky woods

• woods and thickets

• upland slopes

 

Growing Conditions:

• full sun, part shade or shade

• dry to medium moisture well-drained soil

• rich, average loam, clay, gravel or rock

• may tolerate drought conditions once established

 

Plant Height:
• 1-3 feet (60-90 centimeters) tall

 

Stem Description:

• single stem

• slender

• may be slightly pubescent

 

Leaf Description: 

• broadly lanceolate or ovate

• leaves are pointed at both ends

• 1-6 inches (2.5-12.0 centimeters) long

• 0.4-2.5 inches (1-6 centimeters) wide

• three or four sets of leaves spaced far apart along the stem

• one or two of the upper sets of leaves have four in a whorl, the other sets have two opposite leaves. One whorled set may appear in the middle of the stem

 

Leaf Arrangement:

• whorled 

• opposite

 

Leaf Margin:

• entire

• may appear slightly undulate (wavy)

• may be slightly pubescent

 

Leaf Surface:

• smooth and mostly hairless

 

Flowering Period:

• May through July


Flower Description:

• flowers in a loose umbel

• umbels grow at top of stem

• flowers may be upright or drooping

• hoods extend well above stigmatic disc

• horns are long and sharply curve inward toward the center of the stigmatic disc

• corolla reflexed 

 

Flower Color:

• white to pinkish

 

Pod Description:

• erect

• smooth

• hairless to minutely hairy

• long and narrow 

• 3-5.5 inches (7.5-14 centimeters) long

 

Other Information:

• threatened in some New England states

• this species is quite fragrant and attracts a wide variety of insects

• unlike other members of the Asclepias genus, A. quadrifolia is a woodland species

To Locate and Purchase Seeds (when available):

 

Xerces Society Milkweed Seed Finder 

 

Milkweed and Wildflower Vendors

 

Grow Milkweed Plants

 

For More Information About This Species Visit:

 

Lady Bird Johnson Wildflower Center

 

USDA Plants Database

 

Missouri Department of Conservation

 

NatureServe Explorer

 

Wikipedia

 

iNaturalist

 

Text: Woodson, R. (1954). The North American Species of Asclepias L. Annals of the Missouri Botanical Garden, 41(1), 1-211. doi:10.2307/2394652