Nabalus boottii DC.

Boott's rattlesnake-root

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

Boott's rattlesnake-root is a globally-rare species, endemic to the Northeastern United States and represented by a handful of populations in New York and New England, where it occurs only in alpine habitats of Maine, New Hampshire and Vermont. It is named after John Wright Boott (1788-1845) who first collected the plant in 1829 in the White Mountains of New Hampshire.

Habitat

Alpine or subalpine zones, ridges or ledges

Characteristics

Habitat
terrestrial
New England state
  • Maine
  • New Hampshire
  • Vermont
Leaf type
leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
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 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 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
Ray flower color
white
Tuft or plume on fruit
at least a part of the plume is made up of fine bristles
Spines on plant
the plant has no spines
Leaf blade length
20–80 mm
Disk flower number
NA
Show All Characteristics
  • Flowers
    Bract color
    the bracts are not colored or tinged with pink, red or purple
    Bract cycle number
    there is one main cycle of bracts
    Bract outer side hair type
    the bracts are not hairy on their outer surface
    Bract outer side hairs
    the bracts are not 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 of a different shape than the given options
    Bract spines
    the bracts have no spines
    Bract tip shape
    the tips of the bracts acute (have a sharp point)
    Bracts
    the bracts in separate cycles are similar or gradually changing from the outer to inner cycles
    Disk flower color
    NA
    Disk flower lobe number
    NA
    Disk flower number
    NA
    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
    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 rounded across the top
    Flower head shape
    • NA
    • the sides of the flower head are roughly parallel, like a cylinder
    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
    8–12 mm
    Inflorescence shape
    the inflorescence is not flat-topped but appears rounded, with some flower heads distinctly higher than others
    Number of bracts at flower head base
    3–15
    Ovary beak
    • there is a beak on the ovary
    • there is no beak on the ovary
    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 lines or ribs
    • there are seven to nine ribs visible on the ovary
    • there are ten or more ribs visible on the ovary
    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 both carpels and stamens
    Ray flowers
    • 11-15
    • 16-25
    • 6-10
    Ray length
    7–13 mm
    Reproductive system
    NA
    Smaller bracts at base of bracts
    there is no smaller, outer cycle of bracts
    Swelling at base of flower head
    the peduncles are not swollen, or only slightly
    Width of flower head base
    5–6 mm
  • Fruits or seeds
    Number of pappus parts
    11 or more
    Ovary length in developed fruit
    5–6 mm
    Seed hair tuft color
    • the pappus hairs are another color
    • the pappus hairs are tan to dark brown
    Seed hair tuft details
    the pappus hairs are hooked or barbed
    Seed hair tuft length
    6–8 mm
    Seed hair tuft tips
    the pappus hairs are slender
    Seed tuft type
    the pappus is made of very fine hairs or bristles
    Tuft or plume on fruit
    at least a part of the plume is made up of fine bristles
  • Glands or sap
    Sap
    the sap is milky and opaque, and may be white or colored
  • 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 one or more swollen storage organs underground, such as bulbs, tubers or corms
    • there is a thickened taproot on the plant
  • 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
    • 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 is cordate (heart-shaped) or sagittate (arrow-shaped)
    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
    20–80 mm
    Leaf blade shape
    • the leaf blade is elliptic (widest near the middle and tapering at both ends)
    • the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
    • 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 tip
    • the tip of the leaf blade is acute (sharply pointed)
    • the tip of the leaf blade is obtuse (bluntly pointed)
    Leaf blade width
    5–30 mm
    Leaf disposition
    the lower leaves are larger, toothier, and/or on longer stalks than the upper leaves
    Leaf spines
    there are no spines on the leaf edges
    Leaf type
    leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
    Leaflet number
    0
    Specific leaf type
    the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
  • Place
    Habitat
    terrestrial
    New England state
    • Maine
    • New Hampshire
    • Vermont
    Specific habitat
    • alpine or subalpine zones
    • ridges or ledges
  • 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
    • 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

Wetland Status

Not classified

New England Distribution and Conservation Status

Distribution

Connecticut
absent
Maine
present
Massachusetts
absent
New Hampshire
present
Rhode Island
absent
Vermont
present

Conservation Status

Exact status definitions can vary from state to state. For details, please check with your state.

Maine
extremely rare (S-rank: S1), endangered (code: E)
New Hampshire
extremely rare (S-rank: S1), endangered (code: E)
Vermont
extremely rare (S-rank: S1), endangered (code: E)

Native to North America?

Yes

Sometimes Confused With

Nabalus trifoliolatus:
rays green-yellow to yellow-white, axis of capitulescence and stem glabrous, and lower leaf blades pinnately or palmately lobed (vs. N. boottii, with rays white, axis of capitulescence and often upper portion of stem villous-puberulent, and lower leaf blades simple, triangular-sagittate).

Synonyms

  • Prenanthes boottii (DC.) Gray

Family

Asteraceae

Genus

Nabalus

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Information from Dichotomous Key of Flora Novae Angliae

3.  Nabalus boottii DC. NC

Boott’s rattlesnake-root. Prenanthes boottii (DC.) Gray • ME, NH, VT. Alpine plateaus and ridges.