Gumweed

Some 60 species of annuals, biennials, evergreen perennials, and subshrubs are included in this genus, distributed in dry, sunny areas of southern, central, and western N America. A few are grown for their daisy-like, yellow flowers, which are protected when in bud by sticky white resin. Grindelias are unusual in containing up to 21 percent resin - a substance more often associated with trees. Several species, including Grindelia lanceolata and G. squarrosa, were used by native N Americans for bronchial complaints and poison-ivy rash. The latter use was observed by Dr. Canfield of Monterey, California, in 1863, and Grindelia became an official drug, listed in the U.S. Phamacopoeia (1882-1926) and in the U.S. National Formulary (1926-60). Grindelia is named after David Hieronymus Grindel (1776-1836), professor of chemistry and pharmacy in Dorpat, Estonia.

Annual or short-lived, aromatic perennial, with narrowly oblong, toothed, resinous leaves, to 8cm (3in) long, and yellow daisies, about 5cm (2in) across, with resin-coated buds, in summer.


Common Name:
Gumweed
Other Names:
Rosinweed, tarweed, yerba del buey
Botanical Name:
Grindelia camporum syn. G. robusta var. rigida
Genus:
Grindelia
Family:
Asteraceae
Native Location:
California
Cultivation:
Well-drained, poor soil in sun.
Propagation:
By seed sown in spring at 16-19°C (61-66°F); by semi-ripe cuttings in summer.
Harvest:
Plants are cut in full bloom and dried for use in infusions, liquid extracts, and tinctures, or used fresh in poultices. Flowers are preferred for tinctures.
Height:
50cm-1.2m (20in-4ft)
Width:
75cm (30in)
Hardiness:
Z8
Parts Used:
Whole plant
Properties:
A bitter, pungent, aromatic herb that is anti-inflammatory and expectorant, relaxes spasms, and has sedative effects.
Medicinal Uses:
Internally for bronchitis, asthma, whooping cough, and cystitis. Externally for poison-ivy/oak rash, dermatitis, eczema and skin eruptions. Combined with Euphorbia hirta (See, asthma weed), Glycyrrhiza glabra (See, licorice), Inula helenium (See, Japanese Elecampane), Lobelia inflata (See, Chinese lobelia), or Primula veris (See, cowslip) for bronchial complaints. Excess may irritate the kidneys.
Culinary Uses:
The gum is chewed like chewing gum.
Bibliography:
Encyclopedia of Herbs by Deni Brown Copyright © 1995, 2001 Dorling Kindersley Limited Pg 228-229