Butterfly Weed
 
Asclepias tuberosa

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Naturedigger provided all images of butterfly weed for this slide.

Asclepias tuberosa Profile

Common Name(s):

butterfly weed

butterfly milkweed

common butterfly-weed

orange milkweed

pleurisy root

chigger flower

chieger flower

Indian paintbrush

 

Scientific Name:

Asclepias tuberosa

 

Native Range:

United States: AL, AR, AZ, CA, CO, CT, DC, FL, GA, IA, IL, IN, KS, KY, LA, MA, MD, ME, MI, MN, MO, MS,

NC, NE, NH, NJ, NM, NY, OH, OK, PA, RI, SC, SD, TN, TX, UT, VA, VT, WI, WV

 

CANADA: NB, NL, NS, ON, QC

 

USDA Symbol:

ASTU

 

Habitat: 

• dry, rocky or sandy soils

• open woods

• canyons

• glades

• prairies

• fields

• roadsides

 

Growing Conditions:

• full sun

• poor, dry soils

 

Plant Height:
• 1-3 feet (30-60 centimeters)

 

Stem Description:

• hairy

• erect

• light green to dull reddish purple 

• mature plants have multiple stems

 

Leaf Description: 

• narrow, stiff, lance-shaped

• 2.5-3.5 inches long (5-9 centimeters) and 0.5-0.75 inches (1-2 centimeters) wide

• tips are acute

• leaf base is cordate, truncate or rounded

• leaves are sessile or have very short petioles

• upper leaf surface deeper green than underside

 

Leaf Arrangement:

• alternate

 

Leaf Margin:

• entire

 

Leaf Surface:

• glabrous, may be short pubescent

Flowering Period: 

• May through September

Flower Description: 

• hoods are approximately 0.25 inches (6 millimeters) long and horns are slightly smaller around 0.15 inches (3 millimeters)

• horns protrude through the hoods and are sickle-shaped

• corolla (petals) reflexes backwards

• large flat-topped or slightly domed clusters at the top of the stem

• umbels are 1.5 to 2.0 inches (4-5 centimeters) across

• 8-25 flowers per umbel

Flower Color:

• corolla, hoods and horns are bright orange to yellow-orange, rarely red and only yellow if growing in the west

 

Pod Description:

• narrow; grayish green; covered with short hairs

• 3-6 inches (1.5-3 centimeters) long

 

Seed Description:

0.15 inches (0.4 centimeters) long and 0.5-0.75 inches (1.25-2.0 centimeters) across

Other Information:

• used to treat  lung conditions, which is how it got the common name pleurisy root

• unlike other milkweed species, butterfly weed oozes a clear watery sap as opposed to a white, milky sap

• similar in appearance to Asclepias lanceolata, but has a larger number of flowers

• this species has long-lasting blooms and may bloom twice during the season

• the species name tuberosa, refers to the tuberous (knobby tube-like swollen) root of butterfly weed

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

 

Bring Back Monarchs

 

Xerces Regional Milkweed Guide

 

USDA Plants Database