Common Name: Pleurisy Root

General Information

Asclepias tuberosa is an erect, herbaceous perennial plant producing a cluster of usually unbranched, stout stems 75 - 200cm tall from a deep, woody, tuberous rootstock[, ].
The plant was much used by the native North Americans as a food, medicine and source of materials. It is still sometimes used in modern herbalism and as a wild-crafted source of food and fibre. It has a high potential for development as a crop. It is very ornamental and is often grown in gardens, valued especially for its flowers and the butterflies they attract[]. The seedpods are valued for dried flower arrangements[].
Mature plants may freely self-seed in the landscape if seed pods are not removed prior to splitting open[]. They should not be grown outside their native range if the climate strongly suits them, thus making them more likely to invade native habitats[].

Known Hazards

Although no specific reports have been seen for this species, many, if not all, members of this genus contain toxic resinoids, alkaloids and cardiac glycosides. They are only toxic if eaten in large quantities, causing vomiting, stupor, weakness and spasma[, ].
The plants are usually avoided by grazing animals[].

Botanical References

, ,

Range

N. America - Ontario to Quebec and New Hampshire, south to Colorado, northern Mexico, Texas and Florida

Habitat

Dry open sandy and gravelly soils in fields, hillsides, thickets, and open woods; sand dunes and grassy places by the sides of roads[, , , ].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	0.75 m
Pollinators	Bees, Insects, Lepidoptera
Cultivation Status	Ornamental, Wild

Cultivation Details

Plants are hardy to about -20°c[]. Another report says that this species is only suited to the warmer areas of Britain[].
Prefers a well-drained light, rich or peaty soil[, ]. Prefers a sandy soil and a sunny position[, ]. Prefers a slightly acid soil[]. Prefers a dry soil[, ], growing well in poor, dry soils[]. Established plants are drought tolerant[].
A very ornamental plant[], but it is not easy to establish or to keep in British gardens[].
Resents root disturbance[, ], plants should be pot-grown from seed and planted out in their permanent positions when young. Plants are particularly at risk from slugs, however, and some protection will probably be required until the plants are established and also in the spring when the new shoots come into growth[].
Plants are easily grown from seed, but are somewhat slow to establish and may take 2 - 3 years to produce flowers[].
The flower of many members of this genus can trap insects between its anther cells - the struggles of the insect in escaping (especially bees and wasps) pulls with it the pollinium (sacs of pollen) which are then transported to the next flower and deposited there, ensuring pollination of the flower[, ].
This species is only one of two species in the genus that do not have latex canals and therefore do not contain latex[].
A very long-lived plant for a herbaceous perennial[].

Edible Uses

Whilst most parts of this plant have been used as food, some caution is advised since large doses can cause diarrhoea and vomiting - see the notes above on toxicity.

Flower buds - cooked. They taste somewhat like peas[].

Young shoots - cooked. An asparagus substitute[, , , , ].
The tips of older shoots are cooked like spinach[].
One recipe suggests you parboil the leaves or young shoots for three minutes, then discard the bitter water and replace with clean boiling water. (Cold water tends to fix the bitterness.) You can repeat this process p to three times to fully leach any bitterness (and many of the nutrients[]), then cook the leaves for 15 minutes before seasoning them. A pinch of soda can be added during cooking to break down the fibe and improve flavour[].

Young seed pods - cooked. Harvested when 3 - 4 cm long and before the seed floss begins to form, they are very appetizing[, , , , ].

The flower clusters can be boiled down to make a sugary syrup[, , , ]. In hot weather the flowers produce so much nectar that it crystallises out into small lumps which can be eaten like sweets, they are delicious[].

Root - cooked[, , , , , ]. A nutty flavour[]. Some reports say that it is poisonous[].

An edible oil is obtained from the seed[]. The seed is very small, however, and commercial usage would not be very viable.

A latex from the stems can be used as a chewing gum[, , ].

Medicinal

Pleurisy root is a bitter, nutty-flavoured tonic herb that increases perspiration, relieves spasms and acts as an expectorant[]. It was much used by the North American Indians and acquired a reputation as a heal-all amongst the earlier white settlers[, ]. Its main use in present day herbalism is for relieving the pain and inflammation of pleurisy[].
The plant has never been scientifically examined and warrants further investigation[].

The root is antispasmodic, carminative, mildly cathartic, diaphoretic, diuretic, expectorant, tonic and vasodilator[, , , ]. The root was very popular as a medicinal herb for the treatment of a range of lung diseases, it was considered especially useful as an expectorant[, , ]. It has also been used internally with great advantage in the treatment of diarrhoea, dysentery, rheumatism etc[].
A poultice of the dried, powdered roots is used in the treatment of swellings, bruises, wounds, ulcers, lameness etc[, , ].
Use with caution[], This remedy should not be prescribed for pregnant women[]. See also the notes above on toxicity.
The root is harvested in the autumn and can be used fresh or dried[].

Other Uses

A good quality fibre is obtained from the bark and is used in making twine, cloth etc[]. It is easily harvested in late autumn after the plant has died down by simply pulling the fibres off the dried stems[].

The seed floss is used to stuff pillows etc or is mixed with other fibres to make cloth[]. It is a kapok substitute, used in life jackets or as a stuffing material[]. Very water repellent. The floss has also been used to mop up oil spills at sea.

The plant is a potential source of latex, used for making rubber[]. This species is one of only two members of the genus that do not have latex in its sap[, ].

The seedpods contain an oil and a wax which are of potential importance.

Candle wicks are made from the seed floss.

The seed contains up to 21% of a semi-drying oil[].

Propagation

Seed - best sown in a greenhouse as soon as it is ripe in the autumn or in late winter[, ]. We have also had good results from sowing the seed in the greenhouse in early spring[], though stored seed might need 2 - 3 weeks cold stratification[]. Germination usually takes place in 1 - 3 months at 18°c[]. As soon as the seedlings are large enough to handle, prick them out into individual pots and grow them on in the greenhouse for their first winter. Plant out when they are in active growth in late spring or early summer and give them some protection from slugs until they are growing away strongly.
Division in spring. With great care since the plant resents root disturbance. Pot the divisions up and place them in a lightly shaded position in the greenhouse until they are growing away strongly, then plant them out in the summer, giving them some protection from slugs until they are established.. The plant produces a deep taproot and does not transplant well[]. It is unlikely to tolerate division[].
Basal cuttings in late spring. Use shoots about 10cm long with as much of their white underground stem as possible. Pot them up individually and place them in a lightly shaded position in a greenhouse until they are rooting and growing actively. If the plants grow sufficiently, they can be put into their permanent positions in the summer, otherwise keep them in the greenhouse until the following spring and when they are in active growth plant them out into their permanent positions. Give them some protection from slugs until they are established.