• You are here:
• Full Key
• All other flowering non-woody plants
• Daisies, goldenrods, and other aster family plants
• Hieracium robinsonii

Hieracium robinsonii — Robinson's hawkweed

Facts

Robinson's hawkweed is a globally imperiled species, reduced to a single population in northern New Hampshire and a handful in northeastern Canada, although it could be rediscovered in northern Maine. It is confined to open ledges and cliffs along rivers, usually on high-pH bedrock.

Habitat

Shores of rivers or lakes

Characteristics

• Flowers

  Bract cycle number

  there are two main cycles of bracts

  Bract outer side hair type

  the bracts are hairy on their outer surfaces, with hairs having glands (a swelling at the tip of the hair)

  Bract outer side hairs

  the bracts are hairy on their outer surfaces

  Bract tip shape

  • the tips of the bracts acute (have a sharp point)
  • the tips of the bracts are acuminate (tapered to a narrow point)

  Disk flower number

  0

  Disk flower proportions

  NA

  Disk flower reproductive parts

  NA

  Disk flower shape

  NA

  Flower head number

  • each flowering stem has four or more flower heads on it
  • each flowering stem has only one to three flower heads on it

  Flower head outer flowers

  at the outer edge of the flower head, each flower has a single enlarged lobe or strap

  Flower head platform

  the base has no bristles or papery scales

  Flower head profile

  the disk is flat or nearly flat across the top

  Flower type in flower heads

  the flower head has ray flowers only, meaning all of the individual flowers of the flower head have a strap-shaped ray, which may or may not have teeth at the very tip of the ray

  Height of flower head base

  10–15 mm

  Inflorescence shape

  the inflorescence is flat-topped in profile

  Ovary cross-section

  the ovary has five or more corners in cross-section

  Ovary hair type

  the ovary has no hairs on it

  Ovary hairs

  the ovary has no hairs on it

  Ovary profile

  in profile, the ovary is another shape

  Ray flower color

  yellow

  Ray flower reproductive parts

  the ray flowers have both carpels and stamens

  Ray flowers

  26-50

  Reproductive system

  NA

• Fruits or seeds

  Ovary length in developed fruit

  3–5 mm

  Seed hair tuft color

  • the pappus hairs are tan to dark brown
  • the pappus hairs are white or off-white

  Seed hair tuft details

  the pappus hairs are hooked or barbed

  Seed hair tuft length

  4.5–7 mm

  Tuft or plume on fruit

  at least a part of the plume is made up of fine bristles

• Growth form

  Growth form

  the plant has one or more free-standing stems

  Horizontal rooting stem

  there are no stolons

  Plant lifespan

  the plant is perennial, it shows evidence of previous year's leaves, stems or stem bases

  Spines on plant

  the plant has no spines

  Underground organs

  there is a thickened taproot on the plant

• Leaves

  Hairs on underside of leaf blade

  the underside of the leaf is fuzzy or hairy

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade base

  the leaf has a distinct petiole

  Leaf blade base shape

  the base of the leaf blade is cuneate (wedge-shaped, tapers to the base with relatively straight, converging edges), or narrow

  Leaf blade edges

  the edge of the leaf blade has teeth

  Leaf blade length

  20–80 mm

  Leaf blade shape

  • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
  • the leaf blade is oblong (rectangular but with rounded ends)

  Leaf blade tip

  • the tip of the leaf blade is acuminate (tapers to a long, thin point)
  • the tip of the leaf blade is acute (sharply pointed)

  Leaf blade width

  7–20 mm

  Leaf disposition

  the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem

  Leaf spines

  there are no spines on the leaf edges

  Leaf type

  leaves are simple (lobed or unlobed but not separated into leaflets)

  Specific leaf type

  the leaves are simple (lobed or unlobed but not separated into leaflets

• Place

  Habitat

  terrestrial

  New England state

  • Maine
  • New Hampshire

  Specific habitat

  shores of rivers or lakes

• Stem, shoot, branch

  Leaves on stem

  there is at least one full leaf above the base of the flowering stem

  Stem internode hair direction

  the hairs point mostly upwards to outwards

  Stem internode hair type

  at least some of the hairs on the stem have glands

  Stem internode hairs

  the stem has hairs between the nodes

Wetland status

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae