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- Amaranthaceae
- Amaranthus
- Amaranthus retroflexus
Amaranthus retroflexus — red-rooted amaranth
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Facts
Red-rooted amaranth is native to North America and introduced nearly worldwide. In New England it is mainly found in human-disturbed, sandy soils. The young leaves and seeds are edible, and were used for food by many Native American tribes.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields, shores of rivers or lakes
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
- Flower petal color
- NA
- Leaf type
- the 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 is entire (has no teeth or lobes)
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- both the petals and sepals are separate and not fused
- Stamen number
-
- 3
- 4
- 5
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit length
- 1.5–2.5 mm
-
Clonal plantlets
- Bulbils
- the plant does not appear to have bulbils
- Bulblets replace flowers
- there are no bulblets where the flowers are located
-
Flowers
- Anther attachment
- the anther is attached near its midpoint to the filament
- Anther color
- the anthers show no hint of a pink, reddish or purplish tint
- Anther length
- 0.9–1 mm
- Anther opening
- the anthers have narrow slits or furrows that run lengthwise along the anthers
- Anther spurs
- the anthers do not have spurs on them
- Calyx symmetry
- there are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
- Carpels fused
- the carpels are fused to one another
- Cilia on petals
- NA
- Cleistogamous flowers
- there are no cleistogamous flowers on the plan
- Corolla morphology
- NA
- Corolla palate
- NA
- Corona lobe length
- 0 mm
- Epicalyx
- the flower does not have an epicalyx
- Epicalyx number of parts
- 0
- Filament surface
- the filament is smooth, with no hairs or scales
- Flower description
- the flower has a superior ovary, and lacks a hypanthium
- Flower petal color
- NA
- Flower reproductive parts
- the flower has either only pollen- or only seed-producing parts
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Flowers sunken into stem
- no
- Form of style
- the style is lobed at the tip, and unbranched
- Fringed petal edges
- NA
- Fusion of sepals and petals
- both the petals and sepals are separate and not fused
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Hypanthium length
- 0 mm
- Inflorescence length
- 20–300 mm
- Inflorescence one-sided
- the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks
- Inflorescence width
- 10–50 mm
- Inner tepals (Rumex)
- NA
- Marks on petals
- NA
- Nectar spur
- the flower has no nectar spurs
- Number of branches in umbel
- 0
- Number of carpels
- 2–4
- Number of pistils
- 1
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Number of styles
- 3
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- Petal and sepal arrangement
- the flower includes only one cycle of petals or sepals
- Petal and sepal colors
- green to brown
- Petal appearance
- NA
- Petal base
- NA
- Petal folds or pleats
- NA
- Petal glandular dots or scales
- NA
- Petal hairs (Viola)
- NA
- Petal hairs on inner/upper surface
- NA
- Petal length
- 0 mm
- Petal length relative to sepals
- NA
- Petal nectaries
- NA
- Petal number
- 0
- Petal shape
- NA
- Petal tip shape
- NA
- Petal tips (Cuscuta)
- NA
- Petal width
- 0 mm
- Raceme attachment (Veronica)
- NA
- Reproductive system
- each flower has only carpels or only stamens, but both types of flower are present on each plant (monoecious)
- Scales inside corolla
- NA
- Sepal and petal color
- NA
- Sepal appearance
- the sepals are green or brown, and leaf-like in texture
- Sepal appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Sepal color
-
- green to brown
- other
- pink to red
- Sepal length
- 2–4 mm
- Sepal number
- 5
- Sepal orientation
-
- the sepals are pressed against the corolla, or jutting stiffly upward
- the sepals are slightly curved outwards from the corolla
- Sepal relative length
- NA
- Sepal shape
-
- the sepal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)
- the sepal outline is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
- the sepal outline is spatulate (roughly spoon-shaped; narrow near the base, suddenly widening to a rounded tip)
- Sepal texture
- the sepals are thin and dry, paperlike
- Sepal tip shape
- the sepal tip is obtuse (is bluntly pointed)
- Sepals fused only to sepals
- the sepals are separate from one another
- Stamen attachment
- the stamens are not attached to the petals or tepals
- Stamen number
-
- 3
- 4
- 5
- Stamen position relative to petals
- the stamens are lined up with the sepals
- Stamen relative length
- anything
- Stamens fused
- the stamens are not attached to one another
- Staminodes
- there are no staminodes on the flower
- Stigma length
- 0.7–0.9 mm
- Style length
- 0.1–1 mm
- Style petal-like
- the styles are not petal-like
- Umbel flower reproductive parts
- NA
- Upper lip of bilabiate corolla
- NA
-
Fruits or seeds
- Achene relative orientation
- NA
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Capsule ribs
- NA
- Capsule splitting
- NA
- Fruit (pyxis) dehiscence
- the pyxis splits on or near the middle
- Fruit cross-section
- the fruit is at least somewhat flattened
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 1.5–2.5 mm
- Fruit length relative to sepals
- the fruit is shorter than its associated sepals
- Fruit locules
- one
- Fruit shape
-
- the fruit is ellipsoid (widest in the middle and tapering to each end)
- the fruit is obovoid (egg-shaped, but with the widest point above the middle)
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
- the fruit is a pyxis (when dry it splits around the middle, and the top falls off, exposing the seeds)
- Fruit width
- 1–1.3 mm
- Hair type on fruit
- NA
- Hairs on fruit
- the fruits are not hairy
- Legumes (Fabaceae)
- NA
- Mericarp length
- 0 mm
- Mericarp segment shape (Desmodium)
- NA
- Other markings on berry
- NA
- Ovary stipe
- the ovary or fruit does not have a stipe
- Placenta arrangement
- the plant has basal placentation, where one or a few ovules develop at the base of a simple or compound ovary
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Seed length
- 1–1.3 mm
- Seed number
- 1
- Seed relative length
- the seed is about as long as it is wide
- Seed surface
- the seed is smooth or without clear markings
- Seeds comose
- no hairs
- Septum in fruit (Brassicaceae)
- NA
- Wings on fruit
- the fruit does not have wings on it
- prickles on fruits
- the fruits do not have thorn-like defensive structures
-
Glands or sap
- Glands on leaf blade
- the leaf blades do not have glandular dots or scales
- Sap
- the sap is clear and watery
- Sap color
- the sap is clear
-
Growth form
- Growth form
- the plant is an herb (it has self-supporting stems)
- Horizontal rooting stem
- the plant does not have stolons
- Lifespan
- the plant lives only a single year or less
- Parasitism
- the plant is not parasitic
- Plant color
- the leaves or young stems of the plant are green
- Plants darken when dry
- no
- Spines on plant
- the plant has no spines
- Underground organs
- there is a thickened taproot on the plant
-
Leaves
- Bracteole edges
-
- the bracteole margins are entire (without teeth, lobes or hairs)
- the bracteole margins have teeth
- Bracteole length
- 3–6 mm
- Bracteole number (Apiaceae)
- 0
- Bracteole shape
- the bracteoles are subulate (narrowly tapering from the base to the apex; awl-shaped)
- Bracteoles
-
- the plant has bracteoles between the primary bracts and the flowers
- there are no bracteoles on the plant
- Bracts in plantain (Plantago)
- NA
- Final leaf segment length (compound lvs only)
- 0 mm
- Final leaf segment length to width ratio (compound lvs only)
- 0
- Final leaf segment width (compound lvs only)
- 0 mm
- Floral bract texture
- the floral bracts are thin, dry and papery, possibly with a narrow green stripe at the center
- Floral bracts
- the flower has one or more bracts associated with it
- Flower bract length
- 2.5–6 mm
- Hairs on leaf stalk
- the petiole has hairs on it
- Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
- Hairs on upper side of leaf
- the upper side of the leaf is fuzzy or hairy
- Hooked hairs on underside of leaf
- no
- Inflated hairs on leaf
- the leaf blade does not have inflated hairs on it
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade base
- the leaf has a distinct leaf stalk (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
- the base of the leaf blade is rounded
- Leaf blade bloom
- the underside of the leaf has no noticeable bloom
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- the leaf blade has simple hairs with no glands, and not tangled or wooly
- Leaf blade length
- 20–150 mm
- Leaf blade primary vein pattern
- the secondary veins branch off at intervals from the primary vein
- Leaf blade shape
-
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is rhombic (roughly diamond-shaped)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade vein pattern
- the major veins of the leaf blade branch, but do not rejoin
- Leaf blade veins
- the leaf blade has one main vein running from the base towards the tip (it may or may not have secondary veins)
- Leaf blade width
- 10–70 mm
- Leaf duration
- the leaves drop off in winter (or they whither but persist on the plant)
- Leaf form
- the leaves are green, with an expanded blade and a leaf-like texture
- Leaf spines
- there are no spines on the leaf edges
- Leaf stalk
- the leaves have leaf stalks
- Leaf stalk attachment to leaf
- the petiole attaches at the basal margin of the leaf blade
- Leaf stalk base
- the petiole base clasps the stem or sheathes the stem
- Leaf stalk length
- 15–55 mm
- Leaf teeth and lobes
-
- the edge of the leaf blade is entire (has no teeth or lobes)
- the leaf blade margin is wavy, but does not have teeth
- Leaf tip
-
- the tip of the leaf blade is acute (sharply pointed)
- the tip of the leaf blade is obtuse (bluntly pointed)
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf types
- There is a gradual change in appearance of the leaves from the base (or near the base) of the plant to those from further up on the stem, with leaves progressively changing as one moves higher on the stem (often becoming shorter, or less toothed/lobed, and/or with shorter petioles).
- Leaf variation
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaflet number
- 0
- Leaflet petiolules
- NA
- Leaves per node
- there is one leaf per node along the stem
- Pinnately compound leaf type
- NA
- Specific leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Stipels
- NA
- Stipule edges
- NA
- Stipule features
- NA
- Stipule fused to leaf stalk
- NA
- Stipule length
- 0 mm
- Stipule shape
- NA
- Stipules
- there are no stipules on the plant
- Teeth per side of leaf blade
- 0
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
- shores of rivers or lakes
-
Stem, shoot, branch
- Branched tendrils
- NA
- Direction of stem hairs
- the hairs point mostly upwards to outwards
- Flowering stem cross-section
- the flowering stem is circular, or with lots of small angles so that it is roughly circular
- Hair between stem nodes
- the stem has hairs between the nodes
- Hairs between stem nodes
- the hairs on the stem are plain, without glands or branches, and not tangled
- Hooked hairs on stem between nodes
- no
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Plant height
- 20–200 cm
- Stem hair distribution
- the hairs on the stem are distributed more of less uniformly
- Stem orientation
- the stems are upright or angled outwards
- Stem roughness between nodes
- the stem feels rough due to hairs or prickles
- Stem succulence
- the stems are not succulent
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
- Wings on stem
- 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
- unranked (S-rank: SNR)
From Flora Novae Angliae dichotomous key
15. Amaranthus retroflexus L. N
red-rooted amaranth. Amaranthus retroflexus L. var. salicifolius I.M. Johnston • CT, MA, ME, NH, RI, VT. Gardens, fields, roadsides, waste areas, disturbed sandy soils, sandy shorelines.
Native to North America?
Yes
Sometimes confused with
- Amaranthus hybridus:
- sepals of fruit-bearing flowers acute at apex and inflorescence with many, short, croweded, thick branches of flowers (vs. A. retroflexus, with sepals of fruit-bearing flowers rounded to truncate at apex and inflorescence with few to many, slender, lax branches of flowers). Amaranthus powellii: sepals of fruit-bearing flowers acute at apex and inflorescence with few, rigid, widely spaced branches of flowers (vs. sepals of fruit-bearing flowers rounded to truncate at apex and inflorescence with few to many, slender, lax branches of flowers).
Synonyms
- Amaranthus retroflexus var. salicifolius I.M. Johnston