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- Asteraceae
- Asteraceae Group 4
- Achillea
- Achillea ptarmica
Achillea ptarmica — pearl yarrow
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Facts
Pearl yarrow is an introduced horticultural plant from Eurasia that is widely naturalized in the northern half of North America. Even occasional "double-flowered" cultivars may persist outside cultivation.
Habitat
Anthropogenic (man-made or disturbed habitats), coastal beaches (sea beaches), meadows and fields
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade edges
-
- the edge of the leaf blade has no teeth or lobes
- the edge of the leaf blade has teeth
- 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
- Ray flower color
- white
- Tuft or plume on fruit
-
- NA
- there is no plume, or the plume is made up of scales, awns, a crown, or a rim
- Spines on plant
- the plant has no spines
- Leaf blade length
- 30–100 mm
- Flower head width
- 4–8 mm
- Disk flower number
-
- 21-50
- more than 50
-
Flowers
- Bract color
- the bracts are not colored or tinged with with pink, red or purple
- Bract cycle number
- there are three or more cycles of bracts
- Bract outer side hair type
- the bracts are hairy on their outer surfaces, with curled, tangled, matted, or woolly hairs
- 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 oblanceolate (widest near the tip, but otherwise narrow and tapering)
- Bract tip color
- the tips are a different color from the center of the bract
- Disk flower color
- white
- Disk flower lobe number
- 5
- Disk flower number
-
- 21-50
- 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
- 4–8 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 papery scales on it
- Flower head platform surface
- the scales are slightly hairy, at least near the top
- 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)
- the sides of the flower head are roughly parallel, like a cylinder
- Flower head width
- 4–8 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
- Height of flower head base
- 4–5 mm
- Inflorescence branching (Solidago)
- NA
- Inflorescence shape
- the inflorescence is flat-topped in profile
- Inflorescence stem
- the stem of the inflorescence is not hairy
- Number of bracts at flower head base
- 25–30
- Ovary cross-section
- the ovary is compressed (flattened)
- Ovary hair type
- the ovary has no hairs on it
- Ovary hairs
- the ovary has no hairs on it
- Ovary lines or ribs
-
- there are three lines or ribs visible on the ovary
- there are two lines or ribs visible on the ovary
- Ovary profile
-
- in profile, the ovary is oblong (roughly rectangular but rounded at the ends)
- in profile, the ovary is roughly egg-shaped, but widest above the middle
- Ray flower color
- white
- Ray flower reproductive parts
- the ray flowers have carpels or stamens, but not both
- Ray flowers
-
- 1-5
- 11-15
- 6-10
- Ray length
- 3–5 mm
- Reproductive system
- some of the flowers on the plant have only carpels or stamens, while others have both carpels and stamens
- 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
- 2–5 mm
-
Fruits or seeds
- Dispersal unit
- the seeds fall off or are dispersed separately from one another
- Number of pappus parts
- 0
- Ovary length in developed fruit
- 1.5–2 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
-
- NA
- there is no plume, or the plume is made up of scales, awns, a crown, or a rim
-
Glands or sap
- 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
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
-
Leaves
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment width (compound lvs only)
- 0 mm
- Hairs on underside of leaf blade
- 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 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 no teeth or lobes
- the edge of the leaf blade has teeth
- Leaf blade hairs
- NA
- Leaf blade length
- 30–100 mm
- Leaf blade shape
-
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is linear (very narrow with more or less parallel sides)
- 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 acuminate (tapers to a long, thin point)
- Leaf blade veins
- the leaf blade has one main vein running from the base towards the tip
- Leaf blade width
- 2–6 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 stalk length
- 0 mm
- Leaf tip extension
- NA
- Leaf tufts in axils
- there are clusters of smaller leaves growing out of axils
- Leaf type
- leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaflet number
- At least 15
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
- sea beaches
-
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
-
- 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
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
4. Achillea ptarmica L. E
pearl yarrow. CT, MA, ME, NH, RI, VT. Roadsides, fields, abandoned homesteads, gravel beaches.