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- Nabalus
- Nabalus altissimus
Nabalus altissimus — tall rattlesnake-root
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Facts
Tall rattlesnake-root is native to eastern North America, and is found in deciduous forests in New England. The Iroquois made a poultice of the roots of tall rattlesnake root to treat rattlesnake bites.
Habitat
Forests
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 (i.e., 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 lobes, or it has both teeth and lobes
- 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
-
- green to brown
- white
- yellow
- 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
- 40–150 mm
- Disk flower number
- 0
-
Flowers
- Bases of bract appendages
- NA
- 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 linear (long and very narrow)
- Bract tip shape
- the tips of the bracts acute (have a sharp point)
- Disk flower color
- NA
- Disk flower lobe number
- 0
- Disk flower number
- 0
- Disk flower proportions
- NA
- Disk flower reproductive parts
- NA
- Disk flower shape
- NA
- 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 shape
- 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
- 9–14 mm
- Inflorescence branching (Solidago)
- NA
- 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
- 4–6
- Ovary beak
- 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 four to six lines or ribs visible on the ovary
- 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
-
- green to brown
- white
- yellow
- Ray flower reproductive parts
- the ray flowers have both carpels and stamens
- Ray flowers
-
- 1-5
- 6-10
- Ray length
- 7–15 mm
- Reproductive system
- all the flowers on the plant contain 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
- there are no obvious branches on the style
- Swelling at base of flower head
- the peduncles are not swollen, or only slightly
- Width of flower head base
- 2–3 mm
-
Fruits or seeds
- Ovary beak length
- 0 mm
- Ovary length in developed fruit
- 4–5 mm
- Seed hair tuft color
-
- the pappus hairs are pale red to red-brown or purple
- the pappus hairs are white or off-white
- Seed hair tuft details
- the pappus hairs are hooked or barbed
- Seed hair tuft length
- 5–6 mm
- Seed hair tuft tips
- the pappus hairs are slender
- Seed tuft scale number
- 0
- Seed tuft type
- the pappus is made of very fine hairs or bristles
- Top of disk flower ovary
- NA
- Tuft or plume on fruit
- at least a part of the plume is made up of fine bristles
-
Glands or sap
- Leaf blade glands
- the leaf blades have no glandular (translucent) dots or scales
- 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
- 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 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 a distinct petiole
- the leaf has no petiole
- Leaf blade base shape
-
- the base of the leaf blade is truncate (ends abruptly in a more or less straight line as though cut off)
- the base of the leaf is cordate (heart-shaped) or sagittate (arrow-shaped)
- Leaf blade bloom
- there is a noticeable powdery or waxy bloom on the underside of the leaf
- 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 no teeth or lobes
- the edge of the leaf blade has teeth
- Leaf blade length
- 40–150 mm
- Leaf blade shape
-
- the leaf blade is elliptic (widest near 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 surface colors
- there is no noticeable color variation on the upper surface of the leaf
- Leaf blade width
- 20–160 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
- the leaves have no leaf stalks, but attach directly to the stem
- Leaf stalk length
- At least 0 mm
- Leaf tip extension
- NA
- Leaf type
- leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Specific leaf type
-
- the leaf has a row of two or more lobes on each side of the central axis
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
- Teeth per side of leaf blade
- At least 0
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
- forests
-
Scent
- Plant odor
- the plant does not have much of an odor
-
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 bloom
-
- the stem has a powdery or waxy film on it that can be rubbed away
- there is no powdery or waxy film on the stem
- Stem internode hair direction
- the hairs point mostly upwards to outwards
- Stem internode hairs
-
- the stem has hairs between the nodes
- the stem has no hairs between the nodes
- Stem wings
- the stem does not have wings on it
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
- fairly widespread (S-rank: S4S5)
From Flora Novae Angliae dichotomous key
2. Nabalus altissimus (L.) Hook. N
tall rattlesnake-root. Harpalyce altissima (L.) D. Don ex Beck; Nabalus altissimus (L.) Hook. var. hispidulus House; Prenanthes altissima L.; P. altissima L. var. cinnamomea Fern.; P. altissima L. var. hispidula Fern. • CT, MA, ME, NH, RI, VT. Deciduous forests, rarely ascending to high elevation.
Native to North America?
Yes
Sometimes confused with
- Nabalus trifoliolatus:
- each flower head with 9-20 flowers and 7-14 longer involucral bracts (vs. N. altissimus, with each flower head with 5 or 6 flowers and 4-6 longer involucral bracts).
- Nabalus albus:
- each capitulum with 7–9 inner involucral bracts and 9–15 flowers, and pappus deep red-brown (vs. N. latissimus, with each capitulum with 4–6 inner involucral bracts and 5 or 6 flowers, and pappus white to pale yellow).
Synonyms
- Harpalyce altissima (L.) D. Don ex Beck
- Nabalus altissimus var. hispidulus House
- Prenanthes altissima L.
- Prenanthes altissima L. var. cinnamomea Fern.
- Prenanthes altissima L. var. hispidula Fern.