Campanula americana L.

Tall Bellflower

Campanula americana plant

Family - Campanulaceae

Stems - Erect or strongly ascending, to +2m tall, taprooted, herbaceous, simple or sparsely branched, sometimes ridged, with milky sap, hollow, glabrous or occasionally hairy toward tips.

Campanula americana stemStem.

Campanula americana sapStem with milky sap.

Leaves - Alternate, short petiolate to sessile, often with winged petioles, lanceolate to oblong-ovate, serrate with minute prickles at apices of teeth, acuminate-attenuate, to 17cm long, +/-5cm wide, sparsely pubescent above and below. Margins short ciliate. Leaves reduced greatly above to foliaceous bracts.

Campanula americana basal leavesVegetative rosette.

Campanula americana leavesStem leaves.

Inflorescence - 1-3 axillary flowers in upper potion of stems. Flowers subtended by typically 3 foliaceous bracts. The central bracts larger, the lateral bracts small and linear.

Campanula americana inflorescencePortion of inflorescence.

Calyx - Calyx tube 3-4 mm long at flowering, elongating as fruit matures, the lobes 7-12 mm long, 0.8-1.2 mm wide, hairlike to very narrowly triangular.

Campanula americana calyxCalyces.

Flowers - Corolla blue-purple, white at the center, 5 lobed, glabrous, rotate, to 1.5-2.5cm broad. Lobes lanceolate-ovate, to 1cm long, their margins sinuous. Stamens 5, alternating with corolla lobes. Filaments white, flattened, joined at base, densely pubescent on one side, to 4mm long. Anthers yellow, spiraling when mature, 5-6mm long. Style white to lilac, thickened, 5mm long. Stigma purple, 5-6mm long, cylindric, slightly curved at apex. Ovary within calyx tube, 3-locular. Placentation axile. Calyx tube to 5mm long, glabrous, 5-lobed. Lobes 7-8mm long, 1mm broad at base, linear-attenuate, spreading to recurved. Fruiting capsules to +1cm long, +/-4mm in diameter.

Campanula americana flowerFlower.

Campanula americana flower2Flower.

Flowering - June - September.

Habitat - Moist ground, open moist woods, streambanks, roadside ditches.

Origin - Native to U.S.

Other info. - This species is quite common and can be found throughout Missouri. It typically grows as a biennial, with vegetative rosettes of broadly ovate leaves overwintering. The plant is becoming popular in cultivation and grows easily from seed. It would make an attractive addition to any garden.
C. americana is one of the easiest plants to identify while in flower as nothing else in our range even faintly resembles it.

Photographs taken in the Ozark National Scenic Riverways, Shannon County, MO., 7-8-03 (DETenaglia); also in St. Louis County, 8-25-2018 (Kathy Bildner); also at Weldon Spring Conservation Area, St. Charles County, MO, 11-1-2011 and 7-29-2014 (SRTurner).