Centipeda minima — spreading-sneezeweed

Characteristics

• Flowers

  Bract cycle number

  there are two main cycles of 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 shape

  the main bracts are obovate (roughly egg-shaped, but widest near the tip)

  Bract spines

  the bracts have no spines

  Bract texture

  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 orientation

  the bracts are pressed against the plant, or spreading out at the tips

  Disk flower color

  • blue to purple
  • green to brown
  • white
  • yellow

  Disk flower lobe number

  • 3
  • 4

  Disk flower number

  • 11-20
  • 21-50
  • 6-10

  Disk flower reproductive parts

  • the disk flower has both pollen- and seed-producing parts
  • the disk flower has either only pollen- or only seed-producing parts

  Disk flower shape

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

  Flower head number

  each flowering stem has only one to three flower heads on it

  Flower head outer flowers

  at the outer edge of the flower head, the flowers have no enlarged lobe or strap, and are of similar size as those in the center of the disk

  Flower head platform

  the base has no bristles or papery scales

  Flower head platform surface

  NA

  Flower head position

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

  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

  1.5–5 mm

  Flower type in flower heads

  the flower head has disk flowers only, and lacks the strap-shaped flowers

  Inflorescence branching (Solidago)

  NA

  Inflorescence shape

  the flower heads grow in clusters from the axils of the branches or leaves

  Ovary beak

  there is no beak on the ovary

  Ovary cross-section

  • the ovary has five or more corners in 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 lines or ribs

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

  Ovary profile

  in profile, the ovary is roughly egg-shaped, but widest above the middle

  Ovary wing number

  0

  Peduncle hair type

  NA

  Peduncle hairs

  NA

  Peduncle length

  0 mm

  Peduncle orientation

  NA

  Ray flower color

  NA

  Ray flower reproductive parts

  NA

  Ray flowers

  0

  Ray length

  0 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

  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

  Swelling at base of flower head

  NA

  Width of flower head base

  2–3 mm

• Fruits or seeds

  Number of pappus parts

  0

  Ovary length in developed fruit

  1–1.5 mm

  Seed hair tuft bases

  NA

  Seed hair tuft color

  NA

  Seed hair tuft details

  NA

  Seed hair tuft length

  0 mm

  Seed hair tuft tips

  NA

  Seed hairs uniform

  NA

  Seed tuft scale number

  0

  Seed tuft type

  there is no pappus on the ovary

  Top of disk flower ovary

  NA

  Tuft or plume on fruit

  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 annual, it lacks evidence of previous years' growth

  Spines on plant

  the plant has no spines

• Leaves

  Hairs on underside of leaf blade

  • the underside of the leaf is fuzzy or hairy
  • the underside of the leaf is not hairy, or has very few hairs

  Hairs on upper side of leaf blade

  • the upper side of the leaf is fuzzy or hairy
  • the upper side of the leaf is not hairy, or has very few hairs

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade base

  the leaf has no 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 lobes, or it has both teeth and lobes
  • the edge of the leaf blade has teeth

  Leaf blade hairs

  • NA
  • the leaf blade has tangled or woolly-looking hairs

  Leaf blade length

  5–15 mm

  Leaf blade shape

  • the leaf blade is oblong (rectangular but with rounded ends)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
  • the leaf blade is spatulate (spoon-shaped; narrow near the base, then suddenly widening to a rounded tip)

  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 obtuse (bluntly pointed)
  • 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

  1.5–11 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 no leaf stalks, but attach directly to the stem

  Leaf tip extension

  NA

  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

  Massachusetts

  Specific habitat

  man-made or disturbed habitats

• Stem, shoot, branch

  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

  • at least some of the hairs on the stem are tangled, matted or woolly
  • 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

Occurs only in non-wetlands. (Wetland indicator code: UPL)

In New England

From Flora Novae Angliae dichotomous key