Northern Ontario Plant Database

Plant Description

Euthamia graminifolia (L.) Nutt.

En: grassleaf goldenrod, flattop goldenrod, narrowleaf goldenrod, common goldentop, lanceleaf goldenrod
Fr: verge d'or à feuilles de graminée
Oj: wezaawaaskoneg

Asteraceae (Daisy Family)

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General: An erect perennial, 3—15 dm tall, spreading by creeping rhizomes. Stems are smooth (glabrous) or bear vertical lines of fine hairs, and branch in the upper ¼ of the plant. The typical variety (var. graminifolia) of grassleaf goldenrod is the only variety found in Canada. Allergy alert: Goldenrod pollen does not cause hayfever, but goldenrod flowers are frequently visited by wasps and hornets, whose stings can cause anaphylaxis is sensitive workers.

Leaves: Stem leaves are alternate, simple, spreading to ascending, sessile, and smooth (glabrous) to sparsely hairy beneath; upper stem and branch leaves are much smaller than mid-stem and lower leaves; basal leaves are lacking. Leaf blades are narrowly lanceolate to linear, 3.7—13 cm long by 3—12 mm wide, with 1 prominent midrib and 1 or 2 pairs of less prominent veins ± parallel to the midrib. Leaves taper gradually to the base and blunt (obtuse) to sharply pointed (acuminate) apex, margins are entire and finely ciliate.

Flowers: Plants in the Aster Family have flowers arranged in inflorescences called heads, each of which is composed of few to many ray and/or disc flowers attached to a base covered with overlapping rows of bracts (phyllaries), collectively called an involucre. Numerous heads of grassleaf goldenrod flowers occur in terminal flat-topped to domed corymb-like clusters, 1.5—28 cm across. Each head has 21—40 yellow flowers, including 17—22 ray flowers that surround 4—7+ disc flowers. Ray flowers have a flat corolla about 1 mm long and 1/10th as wide, while disc flowers have a tubular corolla 2.6—3.4 mm tall. Involucres are 3—5 mm tall, with 14—16 overlapping phyllaries, which are oblong to ovate with blunt (obtuse) to pointed (acute) tips. Flowers bloom in late summer.

Fruit: Very small ridged achenes, 0.7—1.5 mm long, topped by a pappus of 25—45 pale brown bristles.

Habitat and Range: Dry to moist fields, clearings, roadsides, thickets, shorelines, and open rights-of-way. Grassleaf goldenrod is found throughout the Algoma District and Ontario in a variety of open habitats.

Similar Species: All other goldenrod species in Ontario belong to the genus Solidago and can be recognized by their larger broader leaves with pinnately arranged secondary veins and serrate margins. The most common goldenrod in the Algoma District is the Canada goldenrod (Solidago canadensis) which has large pyramid-shaped flowering heads and obovate leaves with serrate margins. Canada goldenrod and related species have leaves with 3 prominent veins, including the midrib and a pair of secondary veins that separate from the midrib near the middle of the leaf.