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• Amaranthaceae
• Amaranthus
• Amaranthus palmeri

Amaranthus palmeri — Palmer's amaranth

Facts

Palmer's amaranth is native to the southwest United States and Mexico, but it has greatly expanded its range, becoming invasive in many parts of the world. It rarely shows up in the northeast, having been collected in dump sites of nineteenth-century wool carding factories in Massachusetts. This plant was widely used for food by Native Americans of the Southwest.

Habitat

Anthropogenic (man-made or disturbed habitats)

Characteristics

• 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 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

  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 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

  • NA
  • the style is unbranched, but it has two or more narrow appendages that are part of the stigma

  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

  Inflorescence one-sided

  the flowers are arrayed in a spiral around the inflorescence axis or branches, or occur singly, or in several ranks

  Inner tepals (Rumex)

  NA

  Nectar spur

  the flower has no nectar spurs

  Number of pistils

  • 0
  • 1

  Number of sepals, petals or tepals

  there are five petals, sepals, or tepals in the flower

  Number of styles

  2–3

  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 folds or pleats

  NA

  Petal hairs (Viola)

  NA

  Petal number

  0

  Petal tip shape

  NA

  Petal tips (Cuscuta)

  NA

  Reproductive system

  all the flowers on each plant have only carpels or only stamens, with only one type being present on each plant (dioecious)

  Scales inside corolla

  NA

  Sepal and petal color

  NA

  Sepal appendages

  the sepals do not have appendages on them

  Sepal appendages (Oenothera)

  NA

  Sepal number

  5

  Stamen attachment

  • NA
  • NA
  • the stamens are not attached to the petals or tepals
  • the stamens are not attached to the petals or tepals

  Stamen number

  • 0
  • 5

  Stamen position relative to petals

  • NA
  • the stamens are lined up with the sepals

  Staminodes

  there are no staminodes on the flower

  Umbel flower reproductive parts

  NA

  Upper lip of bilabiate corolla

  NA

• Fruits or seeds

  Achene relative orientation

  the achenes are perpendicular to the plane of the perianth (vertical)

  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 features (Brassicaceae)

  NA

  Fruit length

  2–3 mm

  Fruit locules

  one

  Fruit shape

  • the fruit is obovoid (egg-shaped, but with the widest point above the middle)
  • the fruit is spherical

  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)

  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

  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

  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

• Leaves

  Bracteole number (Apiaceae)

  0

  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

  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

  Leaf blade edges

  the edge of the leaf blade is entire (has no teeth or lobes)

  Leaf blade length

  15–70 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 obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
  • 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 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 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 type

  the leaves are simple (i.e., 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).

  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 (i.e., lobed or unlobed but not separated into leaflets)

  Stipels

  NA

  Stipule features

  NA

  Stipules

  there are no stipules on the plant

• Place

  Habitat

  terrestrial

  New England state

  Massachusetts

  Specific habitat

  man-made or disturbed habitats

• Stem, shoot, branch

  Branched tendrils

  NA

  Flowering stem cross-section

  the flowering stem is circular, or with lots of small angles so that it is roughly circular

  Hairs between stem nodes

  • the hairs on the stem are plain, without glands or branches, and not tangled
  • the stem has no hairs between the nodes

  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

  30–130 cm

  Stem roughness between nodes

  the stem does not feel rough

  Tendril origin

  NA

  Tendrils

  the plant does not have tendrils

Wetland status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae