Oxalis corniculata — creeping yellow wood sorrel

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 attachment

  the anther is attached by its base to the filament

  Anther color

  the anthers show no hint of a pink, reddish or purplish tint

  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

  Anther tube length

  0 mm

  Calyx growth after flowering

  the calyx does not grow to cover or partially cover the fruit

  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

  the petal margins do not have cilia

  Cleistogamous flowers

  there are no cleistogamous flowers on the plan

  Corolla morphology

  the tube of the flower is curved upwards

  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 lacks a hypanthium

  Flower length

  4–8 mm

  Flower number

  1–6

  Flower orientation

  the flower points upwards or is angled outwards

  Flower petal color

  yellow

  Flower reproductive parts

  the flower has both pollen- and 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 flower has two or more completely separate styles
  • the style is knob-like at the tip, and unbranched

  Fringed petal edges

  the petals are not fringed

  Fused stamen clusters

  there are two clusters of fused stamens

  Fusion of sepals and petals

  • both the petals and sepals are separate and not fused
  • the petals or the sepals are fused into a cup or tube

  Hairs on flower stalk

  the flower stalk has hairs on it

  Horns in hoods (Asclepias)

  NA

  Hypanthium

  the flower does not have a hypanthium

  Hypanthium length

  0 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

  Interior flower disk

  the flower does not have an interior disc

  Length of flower stalk

  4–20 mm

  Marks on petals

  there are no noticeable marks on the petals

  Nectar spur

  the flower has no nectar spurs

  Number of branches in umbel

  0

  Number of carpels

  5

  Number of pistils

  1

  Number of sepals, petals or tepals

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

  Number of styles

  5

  Ovary position

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

  Perianth shape

  • the perianth is campanulate (bell-shaped, with a tube about as long as wide, flaring at the mouth)
  • the perianth is rotate (platter-shaped, the corolla flattened, circular, with nearly horizontally spreading lobes)

  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 base

  the petal narrows abruptly at the base

  Petal folding in bud

  the petals in bud are rolled like an umbrella, each petal having one edge tucked inside and the other edge exposed (convolute)

  Petal folds or pleats

  the petals of the flower do not have folds or plaits

  Petal glandular dots or scales

  no

  Petal hairs (Viola)

  NA

  Petal hairs on inner/upper surface

  there are no hairs on the inner/upper petal surface

  Petal length

  4–7 mm

  Petal length relative to sepals

  the petals are longer than the sepals

  Petal nectaries

  the petals do not have nectaries

  Petal number

  5

  Petal shape

  • the petal outline is oblong (rectangular, but with rounded ends)
  • the petal outline is obovate (roughly egg-shaped, but with the widest point above the middle of the leaf blade)

  Petal tip shape

  • the petal tip is retuse (with a blunt or rounded apex and a notch at the center)
  • the petal tip is rounded

  Petal tips (Cuscuta)

  NA

  Petal width

  3–4 mm

  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 auricles

  the sepals have no auricles

  Sepal cilia

  the sepals have cilia on their edges

  Sepal color

  green to brown

  Sepal features

  NA

  Sepal length

  3.5–5 mm

  Sepal number

  5

  Sepal orientation

  the sepals are pressed against the corolla, or jutting stiffly upward

  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 oblong (rectangular, but with rounded ends)

  Sepal texture

  the sepals are either very thin but flexible, like a membrane, or they are leaf-like in texture

  Sepal tip shape

  the sepal tip is acute (is sharply pointed)

  Sepal uniformity

  all the sepals are about the same size

  Sepals fused only to sepals

  the sepals are separate from one another

  Spur length

  0 mm

  Spur number

  NA

  Stamen appendages

  stamen appendages are absent

  Stamen attachment

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

  Stamen position relative to petals

  NA

  Stamen relative length

  anything

  Stamens fused

  • the stamens are attached to one another at or near their bases
  • the stamens are not attached to one another

  Staminodes

  there are no staminodes on the flower

  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

  the capsule has five prominent ribs or wings

  Capsule splitting

  the capsule splits by five main valves, teeth or pores

  Fruit (pyxis) dehiscence

  NA

  Fruit beak length

  0 mm

  Fruit cross-section

  the fruit is pentagonal in cross-section

  Fruit features (Brassicaceae)

  NA

  Fruit length

  8–25 mm

  Fruit length relative to sepals

  the fruit is longer than its associated sepals

  Fruit length to width ratio

  4–8.3

  Fruit locules

  five

  Fruit shape

  the fruit is roughly cylindrical (with parallel sides that do not taper, and flat across the top and bottom)

  Fruit stalk orientation

  the fruits curve or droop downwards

  Fruit type (general)

  the fruit is dry and splits open when ripe

  Fruit type (specific)

  the fruit is a capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more seeds)

  Fruit width

  2–3 mm

  Hair type on fruit

  the hairs on the fruits are simple (not branched), don’t have glands, and are not woolly

  Hairs on fruit

  the fruits have hairs on them

  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

  Ovary stipe length

  0 mm

  Placenta arrangement

  the plant has axile placentation, in which the ovules are attached where the septa of a compound ovary are united, usually on the central axis, or to the septa themselves

  Rows of seeds in fruit (Brassicaceae)

  NA

  Schizocarpic fruit compression

  NA

  Schizocarpic fruit segments

  0

  Seed length

  1–1.5 mm

  Seed number

  25–70

  Seed relative length

  the seed is longer than it is wide

  Seed surface

  the seed has parallel ridges on it (ribbed)

  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 more than two years
  • 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 number (Apiaceae)

  0

  Bracts in plantain (Plantago)

  NA

  Floral bracts

  the flower has one or more bracts associated with it

  Flower bract length

  2–4 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
  • the underside of the leaf is not hairy, or it has very few hairs

  Hairs on upper side of leaf

  • the upper side of the leaf is fuzzy or hairy
  • the upper side of the leaf is not hairy, or it has very few hairs

  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
  • whorled: there are three or more leaves 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 base symmetry

  the leaf blade base is symmetrical

  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

  5–18 mm

  Leaf blade primary vein pattern

  the secondary veins branch off at intervals from the primary vein

  Leaf blade shape

  • the leaf blade is cordate (heart-shaped with backward-facing rounded lobes), or sagittate (arrow-shaped with backward-facing pointed lobes)
  • the leaf blade is obovate (egg-shaped, but with the widest point above the middle of the leaf blade)

  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 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

  8–23 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 hair orientation

  • NA
  • the hairs are flat against the leaf surface, mostly pointing towards the leaf tip

  Leaf sheath length

  0 mm

  Leaf shiny

  the upper side of the leaf is dull or slightly shiny

  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 is narrow where it attaches to the stem

  Leaf stalk length

  10–130 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 retuse (blunt or rounded, with a notch at the tip)

  Leaf tufts in axils

  there are no clusters of smaller leaves growing out of axils

  Leaf type

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

  Leaf types

  NA

  Leaf variation

  • the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
  • the lower leaves are larger, toothier, and/or on longer stalks than the upper leaves

  Leaflet number

  3

  Leaflet petiolules

  the leaflets of the compound leaf lack petiolules

  Leaves per node

  there is one leaf per node along the stem

  Specific leaf type

  the leaf has lobes that radiate from the base, somewhat like a hand

  Stipels

  the petiolules have stipels at their bases

  Stipule edges

  the stipule margins do not have teeth

  Stipule features

  NA

  Stipule shape

  the stipules are another shape than the choices given

  Stipules

  the plant has stipules

  Teeth per side of leaf blade

  0

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Vermont

  Specific habitat

  • man-made or disturbed habitats
  • meadows or fields

• Scent

  Plant odor

  the plant does not have much of a smell

• Stem, shoot, branch

  Branched tendrils

  NA

  Direction of stem hairs

  • the hairs are pressed flat against the plant, pointing towards the plant's tip
  • the hairs point downwards, or they bend outwards and then downwards
  • 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

  Up to 50 cm

  Stem bloom

  there is no powdery or waxy film on the stem

  Stem hair distribution

  the hairs on the stem are distributed more of less uniformly

  Stem nodes swollen

  the stem is not swollen at the nodes

  Stem orientation

  the stems trail at the base, but may turn upwards at the tips

  Stem roughness between nodes

  the stem does not feel rough

  Stem spacing

  the plant is growing in tufts, or compact clusters with closely spaced stems, or it is densely matted together in clumps, cushionlike

  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

From Flora Novae Angliae dichotomous key