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• All other flowering non-woody plants
• All other herbaceous, flowering dicots
• Arachis hypogaea

Arachis hypogaea — peanut

Facts

Peanut was probably domesticated in Paraguay or Bolivia around seven thousand years ago, and is now cultivated throughout the tropical and warm-temperate zones of the world. Aside from food, peanuts and peanut oil are used in a wide variety of products. New England occurrences are rare, collected from waste areas in Massachusetts.

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 is only one way to evenly divide the calyx (the calyx is bilaterally symmetrical)

  Carpels fused

  • NA
  • the carpel is solitary or (if 2 or more) the carpels are not fused to one another

  Cleistogamous flowers

  the plant has some cleistogamous flower

  Corolla morphology

  NA

  Corolla palate

  no

  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 a hypanthium

  Flower length

  10–20 mm

  Flower number

  At least 3

  Flower petal color

  yellow

  Flower reproductive parts

  the flower has both pollen- and seed-producing parts

  Flower symmetry

  there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)

  Flowers sunken into stem

  no

  Form of style

  the style is narrow at the tip and unbranched

  Fused stamen clusters

  there is one cluster of fused stamens

  Hairs on flower stalk

  NA

  Horns in hoods (Asclepias)

  NA

  Hypanthium

  the flower has a hypanthium

  Hypanthium length

  30–50 mm

  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

  Length of flower stalk

  0 mm

  Length of peduncle

  0 mm

  Nectar spur

  the flower has no nectar spurs

  Number of carpels

  1

  Number of pistils

  1

  Number of sepals, petals or tepals

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

  Number of styles

  1

  Ovary position

  the ovary is above the point of petal and/or sepal attachment

  Petal and sepal arrangement

  the flower includes two cycles of petal- or sepal-like structures

  Petal and sepal colors

  yellow

  Petal appearance

  the petals are thin and delicate, and pigmented (colored other than green or brown)

  Petal folding in bud

  the petals in bud are arranged in a cycle with edges overlapping like roof shingles (imbricate)

  Petal folds or pleats

  • the petals of the flower do not have folds or plaits
  • the petals of the flower have folds or plaits on them

  Petal hairs (Viola)

  NA

  Petal number

  At least 4

  Petal tips (Cuscuta)

  NA

  Raceme attachment (Veronica)

  NA

  Reproductive system

  all the flowers have both carpels and stamens (synoecious)

  Scales inside corolla

  no

  Sepal and petal color

  the sepals are different from the petals

  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 number

  4–5

  Sepals fused only to sepals

  the sepals are fused to each other (not other flower parts), at least near their bases

  Stamen attachment

  the stamens are attached at or near the bases of the petals or tepals

  Stamen lengths differ

  the stamens are didynamous (two long stamens and two short ones)

  Stamen morphology

  the stamens within a cycle differ in length or width

  Stamen number

  10

  Stigma position

  the stigmas are positioned at the tip of the style

  Style petal-like

  the styles are not petal-like

  Style relative length

  the stigma does not protrude beyond the mouth of the corolla

  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
  • the capsule splits by two main valves, teeth or pores

  Fruit (pyxis) dehiscence

  NA

  Fruit cross-section

  the fruit is round in cross-section

  Fruit features (Brassicaceae)

  NA

  Fruit length

  20–40 mm

  Fruit length to width ratio

  2

  Fruit locules

  one

  Fruit shape

  the fruit is obloid (longer than wide and with rounded ends)

  Fruit stalk orientation

  NA

  Fruit type (general)

  the fruit is dry but does not split open when ripe

  Fruit type (specific)

  the fruit is a legume (a fruit that splits into two valves, but only has a single carpel; think of a pea pod)

  Fruit width

  10–20 mm

  Hair type on fruit

  NA

  Hairs on fruit

  the fruits are not hairy

  Legumes (Fabaceae)

  the legume has none of the mentioned special features

  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

  Ovary stipe length

  0 mm

  Placenta arrangement

  the plant has parietal placentation, where ovules develop on the wall or slight outgrowths of the wall forming broken partitions within a compound ovary

  Rows of seeds in fruit (Brassicaceae)

  NA

  Schizocarpic fruit compression

  NA

  Schizocarpic fruit segments

  0

  Seed number

  1–6

  Seed relative length

  the seed is longer than 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)

  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

  Spines on plant

  the plant has no spines

• Leaves

  Bracteole number (Apiaceae)

  0

  Bracteole shape

  the bracteoles are another shape than those given

  Bracteoles

  the plant has bracteoles between the primary bracts and the flowers

  Bracts in plantain (Plantago)

  NA

  Final leaf segment length (compound lvs only)

  20–40 mm

  Final leaf segment length to width ratio (compound lvs only)

  1.5–2

  Final leaf segment width (compound lvs only)

  6.6–20 mm

  Floral bracts

  the flower has one or more bracts associated with it

  Hairs on leaf stalk

  the petiole has hairs on it

  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)

  Leaf blade length

  50–100 mm

  Leaf blade shape

  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)
  • the leaf blade is ovate (widest below the middle and broadly tapering at both ends)

  Leaf blade surface colors

  the upper side of the leaf blade is relatively uniform in color

  Leaf blade texture

  the leaf blade is herbaceous (has a leafy texture)

  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 length

  50–100 mm

  Leaf teeth and lobes

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

  Leaf tip

  the tip of the leaf blade is rounded, with no point

  Leaf type

  the leaves are compound (made up of two or more discrete leaflets

  Leaflet number

  At least 4

  Leaves per node

  there is one leaf per node along the stem

  Pinnately compound leaf type

  the pinnately compound leaves lack a terminal leaflet (and usually have an even number of leaflets per axis)

  Specific leaf type

  the leaf has a row of two or more lobes on each side of the central axis

  Stipels

  there are no stipels at the bases of the petiolules

  Stipule features

  NA

  Stipule fused to leaf stalk

  the stipules are fused to the petioles for some or most of their length

  Stipules

  the plant has stipules

• Place

  Habitat

  terrestrial

  Specific habitat

  man-made or disturbed habitats

• Stem, shoot, branch

  Branched tendrils

  NA

  Hair between stem nodes

  the stem has hairs between the nodes

  Leaves on stem

  there is at least one full leaf above the base of the flowering stem

  Plant height

  20–100 cm

  Stem orientation

  • the stems are upright or angled outwards
  • the stems trail at the base, but may turn upwards at the tips

  Stem spacing

  the plant is solitary, or a few plants are growing together

  Tendril origin

  NA

  Tendrils

  the plant does not have tendrils

Wetland status

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae