• You are here:
• Dichotomous Key
• Asteraceae
• Asteraceae Group 6
• Ratibida
• Ratibida pinnata

Ratibida pinnata — gray-headed Mexican-hat

Facts

N/A

Habitat

Anthropogenic (man-made or disturbed habitats), forest edges, meadows and fields

Characteristics

• Flowers

  Bases of bract appendages

  NA

  Bract color

  the bracts are not colored or tinged with pink, red or purple

  Bract cycle number

  there are two main cycles of bracts

  Bract keels

  the bracts do not have keels

  Bract outer side hair type

  the bracts are hairy, with simple hairs on their outer surface

  Bract outer side hairs

  the bracts are hairy on their outer surfaces

  Bract shape

  • the main bracts are lanceolate (widest above the base, then taper narrowly towards the tip)
  • the main bracts are linear (long and very narrow)

  Bract spines

  the bracts have no spines

  Bract texture

  the bracts have a similar texture to a leaf

  Bract tip color

  the tips are the same color as the center of the bract

  Bract tip extension appearance

  NA

  Bract tip extension edge

  NA

  Bract tip orientation

  the tips of the bracts curve outwards and downwards from the plant

  Bract width

  1–3

  Bracts

  there are at least two distinct forms of bracts in different cycles

  Disk flower color

  • blue to purple
  • yellow

  Disk flower lobe number

  5

  Disk flower number

  more than 50

  Disk flower reproductive parts

  the disk flower has both pollen- and seed-producing parts

  Disk flower shape

  the disk flower is tube-shaped (cylindrical), or gradually widening like a funnel

  Disk width

  10–13.2 mm

  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 papery scales on it

  Flower head platform surface

  the scales are slightly hairy, at least near the top

  Flower head position

  each of the flower heads is separate on its own peduncle (stalk), not clustered in groups

  Flower head profile

  • NA
  • the disk is conical across the top

  Flower head shape

  NA

  Flower head width

  10–18 mm

  Flower type in flower heads

  the flower head has tubular disk flowers in the center and ray flowers, these often strap-shaped, around the periphery

  Inflorescence branching (Solidago)

  NA

  Inflorescence shape

  the inflorescence is flat-topped in profile

  Inflorescence stem

  hairs are present on the stem of the inflorescence

  Number of bracts at flower head base

  5–15

  Ovary cross-section

  the ovary is compressed (flattened)

  Ovary hair type

  • the ovary has hairs on it, but the hairs have no glands
  • the ovary has no hairs on it

  Ovary hairs

  • the ovary has hairs on it
  • the ovary has no hairs on it

  Ovary profile

  • in profile, the ovary is lance-shaped, but widest above the middle
  • in profile, the ovary is very narrow

  Peduncle hair type

  the hairs on the peduncles are simple (not branched), don’t have glands, and are not woolly

  Peduncle hairs

  the peduncles are hairy

  Peduncle length

  30–270 mm

  Peduncle orientation

  the flower heads are held upright, or slightly angled outwards

  Ray flower color

  yellow

  Ray flower reproductive parts

  there are neither carpels nor stamens in the ray flowers

  Ray flowers

  • 11-15
  • 6-10

  Ray length

  2.5–3.8 mm

  Reproductive system

  all the flowers on the plant contain both carpels and stamens

  Scale tip

  the scales are blunt, with a terminal notch, or straight across the top

  Smaller bracts at base of bracts

  there is a cycle of much smaller bracts outside the cycle of larger and longer bracts

  Style branch number

  the style has two branches

  Style branches

  the style branch is narrow at the tip, or the style branches are narrow at the tips

  Width of flower head base

  8–16 mm

• Fruits or seeds

  Number of pappus parts

  • 0
  • 1
  • 2

  Ovary length in developed fruit

  2–4 mm

  Ovary width in developed fruit

  1.2–3 mm

  Seed hair tuft bases

  NA

  Seed hair tuft color

  NA

  Seed hair tuft details

  NA

  Seed hair tuft length

  At least 0 mm

  Seed hair tuft tips

  NA

  Seed hairs uniform

  NA

  Seed tuft scale number

  0–2

  Seed tuft type

  • the pappus is made of flat scales that are not split or frayed at the tips
  • there is no pappus on the ovary

  Top of disk flower ovary

  NA

  Tuft or plume on fruit

  NA

• Glands or sap

  Bract resin

  the bracts have resin or resin glands

  Leaf blade glands

  the leaf blades have glandular (translucent) dots or scales

  Sap

  the sap is clear and watery

• Growth form

  Growth form

  the plant has one or more free-standing stems

  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 are only slender roots on the plant

• Leaves

  Hairs on underside of leaf blade

  the underside of the leaf is fuzzy or hairy

  Hairs on upper side of leaf blade

  the upper side of the leaf is fuzzy or hairy

  Leaf arrangement

  • alternate: there is one leaf per node along the stem
  • basal: the leaves are growing only at the base of the plant

  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 no teeth or lobes
  • the edge of the leaf blade has teeth

  Leaf blade hairs

  the leaf blade has simple hairs with no glands, and not tangled or wooly

  Leaf blade length

  50–400 mm

  Leaf blade shape

  the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade surface colors

  there is no noticeable color variation on the upper surface of the leaf

  Leaf blade tip

  the tip of the leaf blade is rounded, with no point

  Leaf blade veins

  the leaf blade has one main vein running from the base towards the tip

  Leaf blade width

  30–150 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 stalk

  the leaves have leaf stalks

  Leaf type

  leaves are simple (i.e., lobed or unlobed but not separated into leaflets)

  Specific leaf type

  the leaf has a row of two or more lobes on each side of the central axis

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Massachusetts
  • Vermont

  Specific habitat

  • edges of forests
  • man-made or disturbed habitats
  • meadows or fields

• Stem, shoot, branch

  Flowering stem cross-section

  the flowering stem is circular, or with lots of small angles

  Leaves on stem

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

  Stem bloom

  there is no powdery or waxy film on the stem

  Stem internode hair direction

  • the hairs are pressed flat against the plant, pointing either towards the plant's tip or towards it's base
  • the hairs point mostly upwards to outwards

  Stem internode hair type

  the hairs on the stem are plain, without glands or branches, and not tangled

  Stem internode hairs

  the stem has hairs between the nodes

  Stem wings

  the stem does not have wings on it

Wetland status

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae