Montana Field Guide

Biennial with a stout taproot. Stems erect, simple or branched, 20–100 cm. Herbage glabrate to hirsute. Leaves basal and cauline, petiolate; blades lanceolate to ovate in outline, 5–20 cm long, bipinnate; leaflets deeply lobed, crowded. Umbels compound; peduncles 10–30 cm long; rays unequal, 2–4 cm long; involucral bracts 1–4 cm long, pinnate with widely-spaced, linear lobes; involucel bracts linear or 3-lobed, 4–15 mm long, ciliate. Flowers white; central flower of central umbel often purple; sepals minute; petals ca. 0.5 mm long; stylopodium conical. Mericarps elliptic, slightly compressed parallel to the commissure, 3–4 mm long; ribs with barbed prickles; oil tubes solitary in the intervals (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Whether by name or look, several members of the Apiaceae (Carrot or Parsley) Family can be look-a-likes. These plants are not ones to mis-identify because some are toxic or poisonous. Be conscious of your safety when examining plants. The closest resembling plant to Wild Carrot is Common Caraway (Carum carvi).

Queen Anne's Lace or Wild Carrot - Daucus carota, non-native
* Plants: Hairs sparse (glabrate) to long and stiff (hirsute).
* Stems: Lower portion not purple-spotted. Base is not swollen.
* Leaves: Glabrous and bi-pinnately divided with leaflets being deeply divided. No bulbs in leaf axils.
* Flowers: White with the central flower of the central umbel often purple. Sepals minute.
* Mericarps: Ribs with barbed prickles (not glabrous).
* Roots: Stout taproot.
* Habitats: Along roads, trails, and in fields – often in areas with some disturbance.

Common Caraway - Carum carvi
* Plants: Hairs absent (glabrous).
* Leaves: Glabrous.
* Inflorescence: Small umbellets that are separate from one another. Below the umbel are inconspicuous narrow bracts. Flower stems (peduncles) glabrous.
* Mericarps: Ribbed, and lacking bristles. When crushed the odor smells of caraway.

Poison Hemlock - Conium maculatum, non-native
* Plants: Highly poisonous. Hairs absent (glabrous).
* Stems: Lower portion is purple-spotted. Base is little, to not, swollen.
* Leaves: Glabrous and tri-pinnately divided into small ultimate segments; fern-like. Veins meet with tip of the leaf's tooth. No bulbs in leaf axils.
* Flowers: White. Sepals absent.
* Mericarps: Glabrous, prominent ribs raised, but barely winged and often wavy.
* Roots: Stout taproot.
* Habitats: Moist, disturbed places, such as along streams, ditches, and cool open slopes.

Western Water-hemlock - Cicuta douglasii, native
* Plants: Highly poisonous. Hairs absent (glabrous).
* Stems: Often branched. Lower portion not purple-spotted. Base is swollen.
* Leaves: Glabrous. Bi- to tri-pinnately divided. Tertiary venation twice as long as wide and enclosing sections of the leaflets. Primary lateral veins terminate in the sinuses between the serrations (teeth). No bulbs in leaf axils.
* Flowers: white or greenish.
* Mericarps: Glabrous. Prominent ribs are corky (at least as wide as the darkened intervals), but not winged.
* Roots: Thickened or tuberous. Internally are horizontally divided with cross partitions.
* Habitats: Moist meadows, streambanks, and wetlands.

Spotted Water-hemlock - Cicuta maculata, native
* Plants: Highly poisonous. Hairs absent (glabrous).
* Stems: Often branched. Lower portion not purple-spotted. Base is swollen.
* Leaves: Glabrous and bi- to tri-pinnately divided. Tertiary venation of the leaflet is as long as wide. Primary lateral veins terminate in the sinuses between the serrations (teeth). No bulbs in leaf axils.
* Flowers: White or greenish.
* Mericarps: Glabrous. Prominent ribs are corky (at least as wide as the darkened intervals), but not winged.
* Roots: Thickened or tuberous. Internally are horizontally divided with cross partitions.
* Habitats: Moist meadows, woodlands, streambanks, and wetlands.

Bulb-bearing Water-hemlock - Cicuta bulbifera, native
* Plants: Highly poisonous. Hairs absent (glabrous).
* Stems: Usually solitary. Lower portion not purple-spotted. Base is swollen.
* Leaves: Glabrous. Upper leaves are simple or once-pinnate with bulblets in the axils.
* Flowers: White. Often sterile.
* Mericarps: Ribs thick and raised, wider than the intervals.
* Roots: Thickened or tuberous.
* Habitats: Fens.

Hemlock Water-parsnip - Sium suave, native
* Plants: Hairs absent (glabrous).
* Stems: Solitary. Lower portion not purple-spotted. Base is not swollen.
* Leaves: Glabrous. Emergent leaves are once-pinnate with lance-linear leaflets. Submerged leaves are bi- to tri-pinnately divided with narrower leaflets. Primary lateral veins sometimes terminate in the tips of the serrations (teeth). No bulbs in leaf axils.
* Flowers: White or greenish. Sepals minute.
* Mericarps: Glabrous and elliptical. Ribs corky, but not winged.
* Roots: Fibrous. Internally are horizontally divided with cross partitions.
* Habitats: In shallow fresh water and banks of streams, ponds, and wetlands.

Cow-Parsnip - Heracleum lanatum, native
* Plants: Hairs present.
* Stems: Single, hollow, with short, soft hairs (pubescent). Lower portion not purple-spotted. Base is not swollen.
* Leaves: Veins pubescent. Leaves once-palmately divided into 3 leaflets. Leaflets broad, 3-7 lobed, and coarsely toothed. Petioles are basally dilated. No bulbs in leaf axils.
* Flowers: White and sweet-smelling. Sepals minute.
* Mericarps: Glabrous. Obovate. Dorsal ribs narrow. Marginal (lateral) ribs broadly winged.
* Roots: Stout taproot.
* Habitats: Moist places, such as avalanche slopes, thickets, open forests, woodlands, along streams, and drier wetlands.

Hemlock Parsley - Conioselinum scopulorum, origin and presence unknown
* Plants: Sparsely hairy (glabrate).
* Stems: Single but sparingly branched and hollow. Lower portion not purple-spotted. Petioles are basally dilated. Base is not swollen.
* Leaves: Glabrate, bi- to tri-pinnately divided. Ultimate leaf lobes with one main vein. No bulbs in leaf axils.
* Flowers: White. Sepals absent.
* Mericarps: Glabrous. Elliptical. Dorsal ribs narrowly winged, low and corky. Marginal (lateral) ribs winged.
* Roots: Tuberous and fibrous.
* Habitats: Moist meadows, woodlands, streambanks, and wetlands.

Fields, roadsides; valleys (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

POLLINATORS
The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap: Bombus vagans, Bombus huntii, Bombus rufocinctus, and Bombus impatiens (Thorp et al. 1983, Colla and Dumesh 2010).