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- Nabalus
- Nabalus boottii
Nabalus boottii — Boott's rattlesnake-root
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Facts
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
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
-
- 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
-
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
In New England
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)
From Flora Novae Angliae dichotomous key
3. Nabalus boottii DC. NC
Boott’s rattlesnake-root. Prenanthes boottii (DC.) Gray • ME, NH, VT. Alpine plateaus and ridges.
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