ASCLEPIADACEAE – MILKWEED FAMILY

Plant: herbs, and shrubs Stem: usually with milky juice or sap (latex) Root: : simple, usually entire, mostly paired and opposite, or in whorls of 4, rarely alternate; stipules very small or absent Flowers: perfect, regular (actinomorphic), complex flower; solitary or usually in clusters (umbels) that are flat or round; 5 sepals; 5 petals spreading or swept-back along stem with 5 little horns or hoods (crown) curving into center of flower, no bracts; 5 stamens fused into flower structure; ovary superior, 2 pistils, 1 carpels per pistil, separate with common stigma, many ovules Fruit: pods (follicles), often paired, many seeds with tuffs of silky hairs Other: more common in warm areas; Dicotyledons Group Genera: 250+ genera; locally (common milkweeds), Ampelamus (sandvine), Matelea, Metaplexis + others (introduced)

WARNING – family descriptions are only a layman’s guide and should not be used as definitive Asclepiadaceae (Milkweed Family) – 5 sepals and petals (genus Asclepias has the complex ‘milkweed-type’ flower in umbels with follicles (fruit pods)); Genera Cynanchum, Matelea and Gonolobus have deeply 5-lobed flowers also with follicles (fruit pods); stems often with a milky latex sap; leaves usually simple and entire

Genus Asclepias Genus Cynanchum

Genus Matelea

‘Milkweed-type’ flower

Genus Gonolobus

Umbels Fruit a follicle General Flower Morphology in the Asclepiadaceae Family Cucullus = Hood + Horn (Milkweed-type Flower)

Hood (alternates Corona = hoods with petals) + horns + filaments of the No column in stamens this species

Petals (reflexed, hiding Sepals)

Gynostegium = fusion of Stamens + Stigma head Some have a & carpels separating ‘column’ between hoods and corolla General Flower Morphology and Pollination in the Asclepiadaceae Family (Milkweed-type Flower)

Corpusculum Horn Translator

Pollinium Translator Anther

Hood

Column – present in this species

Stigmatic Slit (opening into the stigmatic chamber) between Anthers

Pollinium (pollinia) are pollen masses from adjacent anther sacs, connected by translators to the corpusculum (like saddle bags). An insects leg pushes into the stigmatic slit and as it pulls the leg out it hooks the the twin pollinia and drags them from the adjacent anther sacs. When the insect visits another milkweed the pollinium may be dragged up the stigmatic slit into the stigmatic chamber and caught – pollination can then proceed in 1 of the ovaries. There are 2 ovaries (2 stigmatic chambers serve 1 ovary, the other 3 the second ovary) so it is possible for 2 follicles to develop if both ovaries are pollinated. ASCLEPIADACEAE – MILKWEED FAMILY

Blunt-Leaved [Sand, Clasping] Milkweed; Asclepias amplexicaulis Sm. Spider [Antelope Horn] Milkweed; Asclepias asperula (Decne.) Woodson Poke Milkweed; Asclepias exaltata L. [Tall] Green Milkweed; Asclepias hirtella (Pennell) Woods. Swamp Milkweed; Asclepias incarnata L. ssp. Incarnata Aquatic [Thin-Leaved; White] Milkweed; Asclepias perennis Walter Purple Milkweed; Asclepias purpurascens L. Fourleaf [Whorled] Milkweed; Asclepias quadrifolia Jacq. Showy Milkweed; Asclepias speciosa Torr. Slim- [Narrow-] Milkweed; Asclepias stenophylla A. Gray Rush Milkweed; Asclepias subulata Decne. Common Milkweed; L. Texas Milkweed; Asclepias texana A. Heller Milkweed [Butterflyweed; Pleurisy Root]; L. ssp. interior Woods. Red-Ring [Variegated] Milkweed; Asclepias variegata L. Whorled Milkweed; Asclepias verticillata L. Green Comet Milkweed; Asclepias viridiflora Raf. Green Antelopehorn [Ozark Milkweed]; Asclepias viridis Walter Gulf Coast Swallow-Wort; Cynanchum angustifolium Pers. Honeyvine [Sandvine; Bluevine; Angle-Pod]; Cynanchum laeve (Michx.) Pers. Angular Fruit Milkvine (Anglepod); Gonolobus suberosus (L.) W.T. Alton Baldwin's Milkvine; Matelea baldwyniana (Sweet) Woodson Oldfield [Climbing] Milkvine; Matelea decipiens (Alexander) Woodson Blunt-Leaved [Sand, Clasping] Milkweed USDA Asclepias amplexicaulis Sm. Asclepiadaceae (Milkweed) Family Oak Openings Metropark, Lucas County, Ohio Notes: milkweed-type flower, greenish-purple, horns pink, hoods and gynostegium (stalked) and hood about equal; leaves oblong, opposite, wavy margin, sessile or nearly so, usually 5 or less pairs; stem glabrous and glaucous; often in sandy ground; summer [V Max Brown, 2005] Spider [Antelope Horn] Milkweed USDA Asclepias asperula (Decne.) Woodson Asclepiadaceae (Milkweed) Family Near Pagosa Springs, Archoleta County, Colorado Notes: milkweed-type flower, pale green to greenish-yellow, calyx spreading, corolla spreading to ascending usually, gynostegium greenish to pale purple, corona deflexed, horns absent; leaves alternate, sessile to very short petiolate, narrowly lanceolate; stem finely hairy; fruit a follicle that looks like an antelope horn; spring to early summer [V Max Brown, 2017] Poke Milkweed USDA Asclepias exaltata L. Asclepiadaceae (Milkweed) Family Pokagon State Park, Steuben County, Indiana Notes: milkweed-type flower, white or slightly tinged with purple, hoods and gynostegium about equal length, loose and drooping umbels; leaves large, ovate, tapering at both ends, short petioles; summer [V Max Brown, 2006] [Tall] Green Milkweed USDA Asclepias hirtella (Pennell) Woods. Asclepiadaceae (Milkweed) Family Kitty Todd Nature Preserve, Lucas County, Ohio Notes: milkweed-type flower, greenish to perhaps slightly purplish, hoods and corolla separated by distinct column, no horns projecting from hoods, hoods about half length of gynostegium; leaves mostly alternate, lanceolate to linear, hairy; summer [V Max Brown, 2007] Swamp Milkweed USDA Asclepias incarnata L. ssp. incarnata Asclepiadaceae (Milkweed) Family Oak Openings Metropark, Lucas County, Ohio Notes: milkweed-type flower, pink to rose-purple (rarely white), hoods and gynostegium about equal length (minus stalk); leaves lanceolate, either with narrowed or rounded base, with petioles; wet areas; summer [V Max Brown, 2004] Aquatic [Thin-Leaved; White] USDA Milkweed Asclepias perennis Walter Asclepiadaceae (Milkweed) Family Mingo National Wildlife Refuge, Stoddard County, Missouri Notes: milkweed-type flower, white (to light pink), petals reflexed and curved back, hoods shorter or about equal to the gynostegium, stalked, solitary umbels from upper leaf nodes; leaves opposite, petiolate, lanceolate, tapering to base, stem short hairy; swamps and wet areas; summer [V Max Brown, 2010] Purple Milkweed USDA Asclepias purpurascens L. Asclepiadaceae (Milkweed) Family Oak Openings Metropark, Lucas County, Ohio Notes: milkweed-type flower, rose-purple to purplish-red, hoods longer than gynostegium; leaves opposite, on short petioles, ovate- lanceolate, short acute tip, veins mostly near 90 degrees from midrib, underside densely wooly; summer [V Max Brown, 2006] Fourleaf [Whorled] Milkweed PurpleUSDA Asclepias quadrifolia Jacq. Asclepiadaceae (Milkweed) Family Alley Springs, Ozark National Riverways, Shannon County, Missouri Notes: milkweed-type flower, usually light pink (rarely cream-colored), hoods longer than gynostegium; leaves opposite, on short petioles, ovate-lanceolate, usually one set of 4 whorled leaves present; spring to early summer [V Max Brown, 2010] Showy Milkweed USDA Asclepias speciosa Torr. Asclepiadaceae (Milkweed) Family Limon, Lincoln County, Colorado Notes: milkweed-type flower, several umbels from upper leaf axils, rose to purple to pinkish, hoods and horns pinkish; leaves elliptical to oblong or ovate, fleshy, opposite, sessile, and usually densely hairy to felty; stem erect, up to 1 m+, usually densely short hairy; fruit a hairy pod; many habitats, often in prairie and rocky areas, along streams; summer (similar to A. syriaca but is usually very hairy and has longer hoods) [V Max Brown, 2014] Slim- [Narrow-] Leaf USDA Milkweed Asclepias stenophylla A. Gray Asclepiadaceae (Milkweed) Family Busiek State Forest and Wildlife Area, Christian County, Missouri Notes: milkweed-type flower, greenish to white, gynostegium little to no stalk, horns appearing often to have 3 lobes (middle being a small horn); leaves linear, mostly alternate, sessile to short stalked, acute tip; stem short hairy; summer [V Max Brown, 2010] Rush Milkweed USDA Asclepias subulata Decne. Asclepiadaceae (Milkweed) Family Red Rock Canyon National Conservation Area, Clarke County, Nevada Notes: an umbel, milkweed-type flower, greenish white, petals strongly reflexed, hoods very long; leaves linear, lost early at flowering; stem “wand-like”, green; fruit a follicle; erect plant to 1+ m; desert areas; spring to early summer [V Max Brown, 2014] Common Milkweed USDA Asclepias syriaca L. Asclepiadaceae (Milkweed) Family Maumee River Metroparks, Lucas County, Ohio Notes: milkweed-type flower, green to pale purple (rarely white), hoods longer than gynostegium (short stalk); leaves opposite, elliptical to oblong, short petioles, soft hairs on underside; very common; hybrids reported; summer [V Max Brown, 2004] Texas Milkweed USDA Asclepias texana A. Heller Asclepiadaceae (Milkweed) Family Friedrich Wilderness Park, Bexar County, Texas Notes: milkweed-type flower, white, petals reflexed and curved back, hoods shorter than gynostegium, stalked, solitary umbels from upper leaf nodes; leaves opposite, on short petioles, ovate-lanceolate, stem very short hairy; erect plant; spring to early summer [V Max Brown, 2010] Butterfly Milkweed [Butterflyweed; USDA Pleurisy Root] Asclepias tuberosa L. ssp. interior Woods. Asclepiadaceae (Milkweed) Family Oak Openings Metropark, Lucas County, Ohio Notes: milkweed-type flower, orange, hoods longer than gynostegium; leaves alternate, hairy beneath, acute tip; stem pubescent, milk or juice colorless; fruit erect; summer to early fall [V Max Brown, 2004] Butterfly Milkweed [Butterflyweed; USDA Pleurisy Root] - Yellow form Asclepias tuberosa L. ssp. interior Woods. Asclepiadaceae (Milkweed) Family Sam A. Baker State Park, Wayne County, Missouri Notes: plant allegedly found along a nearby road and transplanted to flower bed in Sam A. Baker Park. [V Max Brown, 2011] Red-Ring [Variegated] USDA Milkweed Asclepias variegata L. Asclepiadaceae (Milkweed) Family Heber Springs, Cleburne County, Arkansas Notes: milkweed-type flower, 1-6 umbels of up to 30+ flowers, usually white (may be tinted pink), both calyces and corollas usually reflexed (not so in photos below), gynostegium appears stalked (purple colored), hoods longer than gynostegium, horns bent; leaves opposite (occasionally 1 node with 4 leaves whorled), 4 to 7+ nodes, short to long petioles, ovate-lanceolate to somewhat oblong; fruits up to 15 cm long; openings in forests and savannas; spring to summer [V Max Brown, 2018] Whorled [Horsetail] Milkweed USDA Asclepias verticillata L. Asclepiadaceae (Milkweed) Family Maumee River Metroparks, Lucas County, Ohio Notes: milkweed-type flower, greenish to white, hoods about equal to gynostegium; leaves linear and 3-6 whorled, sessile, acute tip; summer to early fall [V Max Brown, 2004] Green Comet Milkweed USDA Asclepias viridiflora Raf. Asclepiadaceae (Milkweed) Family Branson area, Taney county, Missouri Notes: milkweed-type flower, greenish to white, hoods about equal to gynostegium, no horns present; leaves mostly opposite, leaf blades quite variable (linear to lanceolate to ovate), pubescence variable; stem usually finely pubescent; late spring to early fall [V Max Brown, 2008] Green Antelopehorn USDA [Ozark Milkweed] Asclepias viridis Walter Asclepiadaceae (Milkweed) Family Busiek State Forest and Wildlife Area, Christian County, Missouri Notes: milkweed-type flower, pale green to greenish-yellow, calyx spreading, corolla spreading to ascending usually, gynostegium pale purple, corona deflexed, horns absent; leaves alternate, sessile to very short petiolate, elliptical lanceolate; late spring to early summer [V Max Brown, 2010] Gulf Coast Swallow USDA -Wort Cynanchum angustifolium Pers. Asclepiadaceae (Milkweed) Family Sandestin, Walton County, Florida Notes: ; 5-part deeply lobed flower, small, white to greenish white, inside of corolla smooth, in umbels on long from leaf axils; leaves opposite, petiole short, leaf blade linear to very narrowly lanceolate; stem prostrate or often climbing on other vegetation; fruit a pod; costal areas including marshes and salt marshes but not common inland; spring to summer [V Max Brown, 2015] Honeyvine [Sandvine; USDA Bluevine; Angle-Pod] Cynanchum laeve (Michx.) Pers. Asclepiadaceae (Milkweed) Family Waterville, Lucas county, Ohio Notes: vine; 5-part deeply lobed flower, small, white to greenish white, in clusters from leaf axils; leaves large, cordate with a wide sinus to somewhat deltoid, long petiole, sharp-pointed; stem often with dense short hairs; fruit a large pod; an aggressive nuisance vine; summer [V Max Brown, 2008] Angular Fruit Milkvine USDA (Anglepod) Gonolobus suberosus (L.) W.T. Alton Asclepiadaceae (Milkweed) Family Mingo Swamp area, Stoddard County, Missouri Notes: vine; 5-part deeply lobed flower, corollas lanceolate and yellow to yellowish-green, calyces green and much shorter, gynostegium (flat and disc-like) nearly sessile, inflorescence in clusters of few to 25+ flowers from leaf axils; leaves fairly large (to 20 cm), base deeply cordate, long petiole, sharp-pointed; stem with spreading hairs, milky juice; fruit a 5-angled pod; summer [V Max Brown, 2016] Baldwin's Milkvine USDA Matelea baldwyniana (Sweet) Woodson Asclepiadaceae (Milkweed) Family Busiek State Forest and Wildlife Area, Christian County, Missouri Notes: vine; 5-part deeply lobed flower, white to cream colored, in clusters from leaf axils, corolla lobes 7+ mm, sepals hairy; leaves large, cordate, long petiole, sharp-pointed; stem with spreading hairs, milky juice; fruit a pod; late spring to early summer [V Max Brown, 2010] Oldfield [Climbing] Milkvine USDA Matelea decipiens (Alexander) Woodson Asclepiadaceae (Milkweed) Family Sam A. Baker State Park, Wayne County, Missouri Notes: vine; 5-part deeply lobed flower, reddish-brown, petals >3mm wide, corona forms cup around gynostegium, sepals hairy; leaves large, cordate, long petiole; stem with many spreading hairs; fruit a pod; summer (very similar to M. carolinensis) [V Max Brown, 2010]