Tanacetum parthenium — feverfew tansy

Characteristics

• Flowers

  Bases of bract appendages

  NA

  Bract cycle number

  • there are three or more cycles of bracts
  • there are two main cycles of bracts

  Bract keels

  there is one distinct keel on the bracts

  Bract outer side hair type

  • the bracts are hairy, with simple hairs on their outer surface
  • the bracts are not hairy on their outer surface

  Bract outer side hairs

  • the bracts are hairy on their outer surfaces
  • the bracts are not hairy on their outer surfaces

  Bract separation

  the bracts appear completely unconnected to one another on all flower heads

  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)
  • the main bracts are oblong (roughly rectangular but rounded at the ends)
  • the main bracts are ovate (egg-shaped)

  Bract spines

  the bracts have no spines

  Bract texture

  • the bracts appear thin, flexible and nearly translucent
  • the bracts have a similar texture to a leaf

  Bract tip color

  the tips are a different color from the center of the bract

  Bract tip extension appearance

  NA

  Bract tip extension edge

  NA

  Bracts

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

  Disk flower color

  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

  4–9 mm

  Flower head number

  each flowering stem has four or more 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 platform surface

  NA

  Flower head position

  some or all the flower heads are grouped in clusters of two or more

  Flower head profile

  • the disk is flat or nearly flat across the top
  • the disk is rounded across the top

  Flower head shape

  the flower head is hemispherical (like the bottom half of a sphere)

  Flower head width

  6–20 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

  Number of bracts at flower head base

  20–60

  Ovary cross-section

  the ovary has five or more corners in cross-section

  Ovary lines or ribs

  • there are four to six lines or ribs visible on the ovary
  • there are seven to nine ribs visible on the ovary

  Ovary profile

  in profile, the ovary is another shape

  Ovary surface

  the ovary surface has no points, bumps or wrinkles, though it may have lines, ribs or wings

  Ray flower color

  white

  Ray flower reproductive parts

  the ray flowers have carpels or stamens, but not both

  Ray flowers

  • 11-15
  • 16-25
  • 6-10

  Ray length

  2.5–7 mm

  Reproductive system

  some of the flowers on the plant have only carpels or stamens, while others have both carpels and stamens

  Scale tip

  NA

  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 wider at the tip and has a flattened end, or the style branches are wider at the tips and have flattened ends

  Width of flower head base

  6–8 mm

• Fruits or seeds

  Number of pappus parts

  1

  Ovary length in developed fruit

  1–2 mm

  Seed hair tuft bases

  NA

  Seed hair tuft color

  NA

  Seed hair tuft details

  NA

  Seed hair tuft length

  0.2 mm

  Seed hair tuft tips

  NA

  Seed hairs uniform

  NA

  Seed tuft type

  the pappus is made of a circle or rim of lobes or teeth on the ovary

  Top of disk flower ovary

  NA

  Tuft or plume on fruit

  • NA
  • there is no plume, or the plume is made up of scales, awns, a crown, or a rim

• Glands or sap

  Bract resin

  the bracts have no resin or resin glands

  Leaf blade glands

  the leaf blades have glandular (translucent) dots or scales

  Ovary glands

  there are glands on the ovary surface

  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 is a thickened taproot 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 teeth

  Leaf blade hairs

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

  Leaf blade length

  40–100 mm

  Leaf blade shape

  • NA
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
  • the leaf blade is triangular, with the stalk or attachment point on one of the sides

  Leaf blade surface colors

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

  Leaf blade veins

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

  Leaf blade width

  15–40 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 tip extension

  NA

  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
  • the leaf has a row of two or more lobes on each side of the central axis, and each lobe itself has rows of lobes on each side of the lobe's central axis

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • man-made or disturbed habitats
  • meadows or fields

• Scent

  Plant odor

  the plant has a pleasant odor, such as licorice, fruit or resin

• 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 internode hair direction

  • NA
  • 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
  • the stem has no hairs between the nodes

  Stem internode hairs

  • the stem has hairs between the nodes
  • the stem has no hairs between the nodes

Wetland status

Not classified

In New England

From Flora Novae Angliae dichotomous key