Cynanchum louiseae (Vincetoxicum nigrum; Cynanchum n.) Louise’s swallow-wort; black swallow-wort Asclepiadaceae VINI*p; Bx, pb; NY, ct; Q a; K, m; R;

Vincetoxicum nigrum.commons.wikimedia.org

Vincetoxicum nigrum. commons.wikimedia.org (Accessed 7/2014).

Cynanchum louiseae is a perennial, herbaceous, twining vine 1-2 m long, from a large root crown and colonial from rhizomes, usually unbranched. 

Leaves opposite, stalk short; blade 5-10 cm long, oblong to egg-shaped, tip long-pointed, base rounded to slightly lobed. 

cynanchum-louiseae-black-swallow-wort-flowers-title-pic-sleloinvasives-org

Cynanchum louiseae.black swallow wort flowers-title-pic.sleloinvasives.org

Flowers blackish-purple, radially symmetrical, petal lobes 5, triangular, fleshy, 0.2-0.3 cm long; inflorescence, umbrella-shaped, rather few-flowered; blooming June-Sept. 

Cynanchum louiseae. fruit.Leslie J. Mehrhoff.University-of-Connecticut-Bugwood.org.sleloinvasives.org

Cynanchum louiseae. fruit. Leslie J. Mehrhoff. University-of-Connecticut-Bugwood.org.sleloinvasives.org  (Accessed 12/2014).

Fruit dry, hollow pods in pairs, 4-7 cm long, narrowly elliptic; seeds brown, flat to 0.7 cm with winged margin and silky plume (Uva et al. 1997).  

Wetland status: UPL. 

Frequency in NYC: Infrequent. 

Origin: Southern Europe. 

Habitat: Moist, open or partly shaded habitats. 

Notes: Very aggressive, smothering native vegetation, can kill small trees. Listed as one of the NYS ”top twenty” invasive plants by the DEC Natural Heritage Program. 

Asclepias viridiflora green milkweed Asclepiadaceae ASVI; R, gb, sc;

   

Asclepias viridiflora. Eleanor Saulys.ct-botanical-society.org. (Accessed 6/2014).

Asclepias viridiflora. Eleanor Saulys.ct-botanical-society.org. (Accessed 6/2014).

Asclepias viridiflora is a perennial 30-80 cm tall, stems erect to prostrate, often numerous in same area, possibly colonial. 

Leaves opposite, shape very variable, thick, oval to lance-shaped , tip blunt. 

Asclepias viridiflora (green milkweed) flowers close-up. By Keir Morse. Copyright © 2017 Keir Morse. www.keiriosity.com. New England Wild Flower Society. gobotany.newenglandwild.org

Asclepias viridiflora (green milkweed) flowers close-up. By Keir Morse. Copyright © 2017 Keir Morse. www.keiriosity.com. New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 10/2017).

Flowers green, radially symmetrical (see Asclepias Genus), about 1 cm long, crowded, in umbrella-shaped clusters with little or no stalk. 

Fruit dry, pods 8-11 cm long, slender, splitting open to release seeds with silky tufts of hairs. 

Asclepias viridiflora fruit. By Keir Morse. Copyright © 2017 Keir Morse. www.keiriosity.com. New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 10/2017).

Asclepias viridiflora fruit. By Keir Morse. Copyright © 2017 Keir Morse. www.keiriosity.com. New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 10/2017).

Wetland status: UPL. 

Frequency in NYC: NYS Rare, S2, T. 

Origin: Native. 

Habitat: Dry open, sandy soil or rocky barrens. 

Notes: Insect herbivores mostly Hemiptera (bugs), (Wilbur 1976).

Asclepias tuberosa butterfly weed Asclepiadaceae ASTU; Bx, pb, vc; Q, i, j, tl; K; R, sb, sm;

   

Asclepias tuberosa. MBGargiullo. 6.16.2015, yard, Central, NJ. jpg

Asclepias tuberosa. MBGargiullo. 6.16.2015, yard, Central, NJ. jpg

Asclepias tuberosa is a perennial herb, to 70 cm tall, hairy, simple to branched above; stems emerging from a the crown of a stout tap root in May, living up to 25 years, not flowering before about 6 years, 1-few stems per plant, no vegetative reproduction (Klemow and Raynal 1986; Wyatt 1980).Sap clear

Leaves alternate below, opposite on branches, narrowly lance-shaped, to 10 cm long. 

Asclepias tuberosa (butterfly weed) inflorescence. January 2, 2014 copyright © Melton Wiggins. Plants of Southern Alabama  and adjoining areas of Mississippi and Florida. meltonwiggins.com

Asclepias tuberosa (butterfly weed) inflorescence. January 2, 2014 copyright © Melton Wiggins. Plants of Southern Alabama and adjoining areas of Mississippi and Florida. meltonwiggins.com (Accessed 11/2017).

Flowers orange, ca 1 cm, in umbels, radially symmetrical, 5-parted, petals bent downward, stamens fused around style into a central column that is sheathed by a ring of fused scales (hoods), each scale bears a small horn on its internal surface, the entire central structure called the corona, a signature structure of Asclepiadaceae; mostly self-infertile, insect pollinated by bees and butterflies (Wilbur 1976), June-July. 

asclepias-tuberosa-fruit-juvenile-copyright-steve-baskauf-2002-2011-%c2%b7-4

Asclepias tuberosa-fruit-juvenile.© copyright-Steve-Baskauf-2002-2011

Fruit dry, hollow pod, ca 10 cm, thin, erect, seeds brown, flat, numerous, with silky tufts, wind dispersed, Sept.-Oct.. 

Wetland status: UPL. 

Frequency in NYC: Infrequent. 

Origin: Native. 

Habitat: Open, undisturbed, upland areas. Often planted in restorations of meadows and grasslands (Idlewild). 

Notes: Dormant below ground Oct.-May. Seedlings eaten by rabbits; insect herbivores mostly Hemiptera (true bugs), (Wilbur 1976). 

Asclepias syriaca common milkweed Asclepiadaceae ASSY; Bx, cm, pb, sn, vc, wv (Yost et al. 1991); NY, ct, wr; Q, a, cu, fr, i, j, rb, tl, wl; K, fl, m, pl; K, fl (M. Feder 2016); R, bk, c, ca, cg, e, hs, jw, lp, mc, mls, pr, se, sm, ty, wp, wt;

   

Asclepias.syriaca

Asclepias syriaca.M. B. Gargiullo. (ca 2005).

Asclepias syriaca is a perennial herb, 1-2 m tall, stem stout, hairy, usually unbranched, colonial from massive, white, creeping rhizome with storage side shoots; roots can reach over 1 m deep; sap milky, toxic. 

Leaves opposite, stalk 0.5-1.5 cm long, blade 10-26 cm long, 40-18 cm wide, oblong to broadly oval, thick, tip blunt or barely pointed, hairy below. 

Asclepias syriaca flowers close-up. 2002 © Peter M. Dziuk. Minnesota Wildflowers. minnesotawildflowers.info

Asclepias syriaca flowers close-up. 2002 © Peter M. Dziuk. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 10/2017).

Flowers dull pale purple, very fragrant, radially symmetrical, 5-parted, petals bent downward, stamens fused around style into a central column that is sheathed by a ring of fused scales (hoods), each scale bears a small horn on its internal surface, the entire central structure called the corona, a signature structure of Asclepiadaceae (see Asclepias Genus); inflorescence of large, rounded umbels; obligate outcrosser (self-incompatible) produces nectar 24 hrs per day, daytime pollinators include bees (Apis mellifera), wasps (Microbembex monodontaTiphia clypeata), flies and butterflies, nocturnal pollinators moths (Jennersten and Morse 1991; Rau and Rau 1970), June-Aug.

asclepias-syriaca-apocynaceae-common-milkweed-oldfield-falmouth-ma-82015

Asclepias syriaca Apocynaceae common milkweed.oldfield Falmouth, MA 8/2015 M.B. Gargiullo

Fruit pale green, becoming dry, a pod to 12 cm long, broad around middle, tip pointed, base round, surface warty, hairy, held upright on bent stalk, splitting open to release seeds; seeds numerous, ca 0.9 cm, flat, brown, with white silk tuft, preyed upon by the weevil Oncopeltus fasciatus (Handel 1983), wind dispersed Sept., Oct. (Levine 1995). Seeds will not germinate until at least a year after dispersal (Bhowmik and Bandeen 1976). Winter stalks often with empty pods still attached. 

Asclepias syriaca seeds in pod, close-up. 2007 © Peter M. Dziuk. Minnesota Wildflowers. minnesotawildflowers.info

Asclepias syriaca seeds in pod, close-up. 2007 © Peter M. Dziuk. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 10/2017).

Wetland status: UPL. 

Frequency in NYC: Common 

Origin: Native. 

Habitat: Open areas, old fields, roadsides, fill, abandoned lots. 

asclepias-syriaca-fruit-and-seeds-commons-wikimedia-org

Asclepias syriaca.fruit and seeds.commons.wikimedia.org (Accessed 10/2016).

Notes: Plants need at least 30% full sun (Bhowmik and Bandeen 1976). Eaten by Curculionid and Cerambycid beetles (milkweed beetle, Tetraopes teraophtalmus) and Lygaeid bugs (milkweed stink bug Lygaeus kalmii), (Wilbur 1976; Broyles and Wyatt, 1988; Bhowmik and Bandeen 1976). Attacked by aphids that are in turn preyed upon by a number of other insects including ants (Formica fusca), beetles (Coccinella transversoguttataBrachyacantha ursina, and Adalia bipunctata). Common milkweed is parasitized by several fungi, the most frequent of which Cercospora clavata. The sap is home to flagella bacteria (Bhowmik and Bandeen 1976). Considered to be toxic (Kingsbury 1964).  

Asclepias quadrifolia four-leaved milkweed Asclepiadaceae ASQU; Bx, vc; R (DeCandido 2001);

   

Asclepias quadrifolia (whorled milkweed). By Henry Domke. Published May 22, 2014. Prairie Garden Trust. PGT Nature Garden. pgtnaturegarden.org

Asclepias quadrifolia (whorled milkweed). By Henry Domke. Published May 22, 2014. Prairie Garden Trust. PGT Nature Garden. pgtnaturegarden.org (Accessed 10/2017).

Asclepias quadrifolia is a perennial herb to 50 cm tall, stems slender, mostly unbranched, sap milky, lower stem leafless, upper stem usually with 3 leaf-bearing nodes. 

Leaves of upper and lower nodes opposite, small, middle node with a whorl of four, much larger leaves, blades thin, to 12 cm long, lance to egg-shaped, tip long-pointed, base wedge-shaped. 

Flowers radially symmetrical, petal lobes pale pink to 0.6 cm, hoods white (see Asclepias Genus); inflorescence of umbrella-shaped clusters; June-July. 

Asclepias quadrifolia fruit. Martha Baskin. Nantahala National Forest Natives, NC. blog.jpeg

Asclepias quadrifolia fruit. Martha Baskin. Nantahala National Forest Natives, NC. blog.jpeg (Accessed 10/2017).

Fruit dry, a pod filled with plumed seeds, very slender, to 12 cm long tapered at both ends, held erect on unbent stalks. 

Wetland status: UPL. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Dry, open woods.

Asclepias purpurascens purple milkweed Asclepiadaceae ASPU; Bx, pb, vc; Q (DeCandido 2001); R, gb;

   

Asclepias purpurascens,© Copyright Sheryl Pollock 2011 · 8.discoverlife.org

Asclepias purpurascens,© Copyright Sheryl Pollock 2011 · 8.discoverlife.org

Asclepias purpurascens is a perennial herb to 1 m tall; stem erect, finely hairy, sap milky. 

Leaves opposite, stalk to 0.8 to 2.5 cm long, blade 10-15 cm long, elliptic to egg-shaped, finely hairy below, smooth above, base contracted. 

Flowers dark purple, to 1 cm, radially symmetrical (see A. syriaca); inflorescence umbrella-shaped, one or a few flowered, at top of stem; June-July. 

Asclepias purpurascens fruit. R. W. Smith. University of Michigan Herbarium. michiganflora.net

Asclepias purpurascens fruit. R. W. Smith. University of Michigan Herbarium. michiganflora.net (Accessed 10/2017).

Fruit dry, hollow pods 10-15 cm, filled with plumed seeds, held erect, hairy but not warty. 

Wetland status: FACU. 

Frequency in NYC: Infrequent. Rare (NYS S3 U),

Origin: Native. 

Habitat: Upland open woods, meadows.

Asclepias incarnata swamp milkweed Asclepiadaceae ASIN; Bx, pb; Q, j, wl; K, p; R, ah, c, e, h, gr (x), is, lp, sb, v;

   

Asclepias incarnata.Frank Bramley. Copyright © 2014 New England Wild Flower Society.gobotany.newenglandwild.org

Asclepias incarnata.Frank Bramley. Copyright © 2014 New England Wild Flower Society.gobotany.newenglandwild.org (12/2014).

Asclepias incarnata is a perennial herb to 1.5 m tall, stems leafy, branched above, stems single or clumped, sap milky. 

Leaves opposite, to 20 cm long, lance-shaped, tip pointed, base blunt to slightly lobed. 

MA.7/26/08 Great Sippewissett Marsh.JPG

Asclepias Incarnata (swamp milkweed).close-up.Richard Payne. Falmouth, MA, Great Sippewissett Marsh.JPG

Flowers pink about 0.8 cm, in umbrella-shaped clusters insect pollinated, July- Aug. 

Asclepias incarnata fruit and plumed seeds. 2008 © Peter M. Dziuk .Minnesota Wildflowers. minnesotawildflowers.info

Asclepias incarnata fruit and plumed seeds. 2008 © Peter M. Dziuk .Minnesota Wildflowers. minnesotawildflowers.info (12/2014).

Fruit dry pods, narrow, to 9 cm, long pointing upwards, finely hairy, splitting open length-wise to release flat, brown seeds with white plumb, wind dispersed through autumn. Plants occasionally fed upon by Chrysomelid beetles (Labidomera clivicollis) and larvae of monarch butterflies (Wilbur 1976; Bhowmik and Bandeen 1976; Dillon and Dillon, 1972). 

 Wetland status: OBL. 

Frequency in NYC: Occasional. 

Origin: Native. 

Habitat Open, undisturbed wet areas, marshes, tolerate soil pH 5-8. 

Asclepias exaltata poke milkweed Asclepiadaceae ASEX; Bx, vc; Q; R (DeCandido 2001);

   

Asclepias exaltata (poke mulkweed).MBGargiullo.Shenendoah Nat. Pk. Big Meadow.8/9/92

Asclepias exaltata (poke milkweed) flowers. MBGargiullo.Shenendoah Nat. Pk. Big Meadow.8/9/92

Asclepias exaltata perennial herb from a rhizome, stem 50-150 cm tall, sap milky. 

Leaves opposite, 7-11 pairs, stalk 1-2 cm long, blade 10-30 cm long, 10 cm wide, broadly elliptic, thin, elongate-pointed at both ends, usually hairless. 

Flowers white to dull purple, radially symmetrical (regular), petal lobes to 1 cm long, hoods 0.4 cm (see A. syriaca); inflorescence of loose, few-flowered umbels in upper axils and end of stem, flowers often drooping on stalks to 5 cm long; June-July. 

Asclepias exaltata (poke-milkweed) fruit. © K. Chayka. Minnesota Wildflowers. minnesotawildflowers.info

Asclepias exaltata (poke-milkweed) fruit. © K. Chayka. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 10/2017).

Fruit dry pods, narrow, to 15 cm long, erect, stalks bent, splitting open lenghtwise to release plumed seeds, wind dispersed. 

Wetland status: FACU. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Rich, moist woods. 

Asclepias amplexicaulis blunt-leaved milkweed Asclepiadaceae  ASAM; Bx, vc; R (DeCandido 2001);

  

Asclepias amplexicaulis. Emmet J. Judziewicz  Robert W. Freckmann Herbarium. University of Wisconsin at Stevens point.wisplants.uwsp.edu

Asclepias amplexicaulis. Emmet J. Judziewicz Robert W. Freckmann Herbarium. University of Wisconsin at Stevens point.wisplants.uwsp.edu (Accessed 12/2014).

Asclepias amplexicaulis is a perennial herb from a rhizome, to 80 cm tall, sap milky, plant usually pale, waxy-green (glaucous). 

Leaves opposite, oval to broadly oblong, 7-15 cm long, tip blunt, base usually lobed, clasping stem, margin often wavy. 

Flowers greenish-purple and pinkish, radially symmetrical (regular) to 1.8 cm long (see A. syriaca); inflorescence, terminal, umbrella-shaped, on a stalk 10-30 cm long, flowers numerous; May-July. 

Asclepias amplexicaulis (blunt-leaved milkweed).MBGargiullo.NJ Pine Barrens Rt.530 off Rt 70.7/25/92

Asclepias amplexicaulis (blunt-leaved milkweed).MBGargiullo.NJ Pine Barrens Rt.530 off Rt 70.7/25/92

Fruit dry, hollow pods, slender, elongate 10-13 cm long, erect on bent stalks; splitting open to release plumed seeds, dispersed by wind. 

Wetland status: UPL. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Dry open habitats, sandy soil.  

Asclepias Genus milkweed Asclepiadaceae

  

Asclepias incarnata (swamp milkweed).MBGargiullo ca. 1992.jpg

Asclepias incarnata (swamp milkweed).MBGargiullo, Central NJ, ca. 1992.jpg

Asclepias is a perennial herbs from a thick root, or vertical root crown, sap is a milky, thick latex, (except A. tuberosa) often containing toxic cardiac glycosides (chemically a sugar and steroid combined). 

Leaves opposite to whorled (alternate in A. tuberosa). 

Asclepias syriaca ( Milkweed Common) flower parts. Photo © Belinda Beethan (Native Plant Society of New Jersey) 6/20/2012. Showing close up of flowers

Asclepias syriaca ( Milkweed Common) flower parts. Photo © Belinda Beethan (Native Plant Society of New Jersey) 6/20/2012. Showing close up of flowers (Accessed 8/2017).

Asclepias flower.botany.Center for the Study of Digital Libraries Texas A&M University. csdl.tamu.edu Accessed 12/2014).

Asclepias flower.botany.Center for the Study of Digital Libraries Texas A&M University. csdl.tamu.edu Accessed 12/2014).

Flowers radially symmetrical, 5-parted, petals (corolla) fused at base, petal lobes usually reflexed sharply backward; stamens fused around style into a central column, anther tips triangular, column sheathed by a ring of five petal-like “hoods” often with a horn-like structure inside each hood, the entire central structure called the “corona,” a signature structure of Asclepiadaceae; pollen stuck together in two masses (pollinia) connected by a strap of tissue, not visible from outside of flower; ovary superior; stigma large (Yatskievych 2006). 

Asclepias syriaca (common milkweed) seed dispersal. Del Orloske MALD 10/2017 2

Asclepias syriaca (common milkweed) seed dispersal. Del Orloske MALD 10/2017

Fruit dry, linear to oval pods, tip pointed, usually held erect; eventually splitting open lengthwise to release numerous plumed seeds. 

Asclepias incarnata (swamp milkweed) with Danaus plexippus (monarch butterfly larva). Michael Feder. 8/2017

Asclepias incarnata (swamp milkweed) with Danaus plexippus (monarch butterfly) larva. Michael Feder. 8/2017

Asclepias syriaca (common milkweed) with Aphis nerii (Oleander aphid). © 2006 Jeffery Pippen. jeffpippen.com

Asclepias syriaca (common milkweed) with Aphis nerii (Milkweed aphid). © 2006 Jeffery Pippen. jeffpippen.com (Accessed 10/2017).

Notes: Pollen is dispersed when the pollen mass (pollinia) strap becomes tangled on the legs of bees or other insect visitors (Conrad 2006). Plants are eaten by larvae of monarch butterflies (Danaus plexippus), and also by the milkweed tiger moth (Euchaetes egle), which store cardiac glycoside toxins, making them unpalatable to birds (Brower and Brower 1964; Brower 1972).   Parasitized by the bright orange Oleander aphid Aphis nerii, that sequesters cardiac glycosides present in milkweeds. This insect is in turn parasitized by a braconid wasp, Lysiphlebus testaceipes, (McAuslane 2001). Fed on by Tetraopes tetrophthalmus the milkweed long-horned beetle.

Euchaetes egle (milkweed tiger moth; ID Mike Feller) on Asclepias tuberosa. MBGargiullo. 8/2017 Central NJ. 8/2017

Euchaetes egle (milkweed tiger moth; ID Mike Feller) on Asclepias tuberosa. MBGargiullo. Central NJ. 8/2017