White Bog Orchid

Habenaria dilatata

Species distinguishing characteristics: 

  • Dense, upright cluster of bright white, highly fragrant flowers
  • Flowers have 2 wing-like sepals, a hood, and a lower lip with a spur
  • Leafy stems with alternate, lance-shaped leaves
  • Grows in boggy wet areas

Family Characteristics: 

  • Clusters of flowers (occasionally singly) with 3 sepals and 3 petals
  • Lowest petal of each flower forms a flared or pouch-like lip
  • Fruit is a dry capsule with millions of tiny seeds
  • Leaves simple, alternate, and stalkless
  • Largest family of flowering plants - includes vanilla orchids, whose pods provide vanilla flavoring

Growth habitat: 

Erect perennial, 15–100 cm tall, with smooth, hairless foliage.

Leaves and stems: 

Unbranched stem with alternate leaves and densely covered with flowers at the top.  Oblong and blunt-tipped or lance shaped leaves, 4–10 cm long and 1–3 cm wide, are stalkless, sheathing the stem, and gradually smaller towards the top of the stem.

Flowers: 

Tall cluster, 5–30 cm long, of white to greenish-tinged, waxy flowers with bracts at bases.  Flowers, about 1.5 cm across, have 2 wing-like, horizontal sepals, a round upper hood formed by the other sepal, and 2 erect petals.  The lower lip of the flower has a slender cylindrical, downward curved spur to the rear that is half to twice as long as the lip.  Flowers are often detected before the plant is noticed as it exudes a very fragrant, somewhat spicy aroma.

Roots: 

Fleshy, tuber-like roots.

Seeds: 

Erect, oval capsule with abundant tiny seeds.  Seeds lack the starchy reservoir that surrounds most seeds, and must receive nutrients from an associated fungus in order to germinate.

Habitat preferences: 

Wet sites in meadows, forests, clearings, bogs, swamps, fens, marshes, wet meadows, and along springs, streams and lake edges from low to subalpine elevations.

Interesting facts: 

The spur length is highly variable in this species and may serve to attract varying species of moths (Lepidoptera spp.), butterflies (Papilionoidea spp.), bees (Apoidea spp.) and flies (Diptera spp.).  The spur is essentially a nectar-filled pouch.  The flowers are highly evolved to ensure that insects are unable to extract nectar from one flower without pollinating the next flower.  Hairs inside the flower entangle the insect long enough for the flower to attach sticky disks of pollen to the insect’s forehead.

Biological Classification: