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- Diodia virginiana
Diodia virginiana — Virginia buttonweed
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Facts
Virginia buttonweed is native to the eastern U.S., reaching the northern edge of its range just south of New England. It is a spreading, prostrate perennial that can show up as a weed in lawns and other disturbed areas of the south. However, it is listed as rare farther north in New Jersey and Indiana. Look for its distinctive, four-parted white flowers borne in the leaf axils along floppy, squarish stems. The opposite leaves are joined across the stem by a hairy tissue, and they sometimes are mottled yellow due to a virus. It has thick roots by which it can spread vegetatively. It resembles Diodia teres, but the latter is much more upright-growing, much hairier, and has narrower leaves.
Habitat
Anthropogenic (man-made or disturbed habitats)
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
- Flower petal color
-
- pink to red
- white
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- opposite: there are two leaves 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 four petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- Stamen number
- 4
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Fruit length
- 0.6–0.9 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
- 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 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 an inferior ovary, with or without a hypanthium
- Flower petal color
-
- pink to red
- white
- 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
- Fusion of sepals and petals
- the petals or the sepals are fused into a cup or tube
- 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
- 1
- Number of sepals, petals or tepals
- there are four petals, sepals, or tepals in the flower
- Petal and sepal arrangement
- the flower includes two cycles of petal- or sepal-like structures
- Petal and sepal colors
-
- pink to red
- white
- Petal appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal hairs (Viola)
- NA
- Petal number
- 4
- Petal tips (Cuscuta)
- 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 appendages
- the sepals do not have appendages on them
- Sepal appendages (Oenothera)
- NA
- Stamen attachment
- the stamens are not attached to the petals or tepals
- Stamen number
- 4
- Stamen position relative to petals
- the stamens are lined up with the petals
- 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
- NA
- Achene shape
- NA
- Achene surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Capsule ribs
- NA
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 0.6–0.9 mm
- Fruit locules
- two
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Fruit type (specific)
- the fruit is a schizocarp (when dry it splits into sections, each holding one or more seeds)
- Legumes (Fabaceae)
- NA
- 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 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
- Septum in fruit (Brassicaceae)
- NA
- 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
- 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
- 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
- Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
- Leaf arrangement
- opposite: there are two 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 edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf blade length
- 20–32 mm
- Leaf blade shape
-
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is oblanceolate (lance-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 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 teeth and lobes
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaflet number
- 0
- Leaflet petiolules
- NA
- Leaves per node
- there are two leaves 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 features
- NA
- Stipules
-
- the plant has stipules
- there are no stipules on the plant
-
Place
- Habitat
- terrestrial
- New England state
- Connecticut
- Specific habitat
- man-made or disturbed habitats
-
Stem, shoot, branch
- Branched tendrils
- NA
- Flowering stem cross-section
- the flowering stem is roughly square
- 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
- 20–80 cm
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- absent
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
2. Diodia virginiana L. var. virginiana E
Virginia buttonweed. Diodia hirsuta Pursh; D. tetragona Walt. • CT. Gardens, waste areas.
Native to North America?
Yes
Sometimes confused with
Synonyms
- Diodia hirsuta Pursh
- Diodia tetragona Walt.