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Euphorbia polygonifolia — seaside sandmat

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New England distribution

Adapted from BONAP data

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North America distribution

Adapted from BONAP data

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Facts

Contact with the latex of seaside sandmat can cause poison ivy-like symptoms on the skin.

Habitat

Coastal beaches (sea beaches), dunes

Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
Flower petal color
NA
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
  • NA
  • there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
Number of sepals, petals or tepals
there are no petals, sepals, or tepals in the flower, or they are not clearly present
Fusion of sepals and petals
NA
Stamen number
1 or 2
Fruit type (general)
  • the fruit is dry and splits open when ripe
  • the fruit is dry but does not split open when ripe
Fruit length
3–4.5 mm
Show all 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 growth after flowering
    NA
    Calyx symmetry
    NA
    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
    NA
    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 number
    At least 3
    Flower petal color
    NA
    Flower reproductive parts
    the flower has either only pollen- or only seed-producing parts
    Flower symmetry
    • NA
    • 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
    Fringed petal edges
    NA
    Fused stamen clusters
    NA
    Fusion of sepals and petals
    NA
    Hairs on inflorescence
    at least some of the hairs on the axis of the inflorescence have glands
    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 has an interior disc
    Marks on petals
    NA
    Nectar spur
    the flower has no nectar spurs
    Number of carpels
    3
    Number of pistils
    1
    Number of sepals, petals or tepals
    there are no petals, sepals, or tepals in the flower, or they are not clearly present
    Number of styles
    3
    Ovary position
    the ovary is above the point of petal and/or sepal attachment
    Perianth shape
    NA
    Petal and sepal arrangement
    the flower includes neither petals nor sepals
    Petal and sepal colors
    NA
    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
    NA
    Sepal appendages
    NA
    Sepal appendages (Oenothera)
    NA
    Sepal auricles
    NA
    Sepal cilia
    NA
    Sepal color
    NA
    Sepal features
    NA
    Sepal length
    0 mm
    Sepal number
    0
    Sepal orientation
    NA
    Sepal relative length
    NA
    Sepal shape
    NA
    Sepal texture
    NA
    Sepal tip shape
    NA
    Sepal uniformity
    NA
    Sepals fused only to sepals
    NA
    Stamen number
    1 or 2
    Stamens fused
    the stamens are not attached to one another
    Staminodes
    there are no staminodes on the flower
    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
    • the capsule has no prominent ribs or wings
    Capsule splitting
    • NA
    • the capsule splits by three main valves, teeth or pores
    Carpel beak length
    0 mm
    Fruit (pyxis) dehiscence
    NA
    Fruit beak length
    0 mm
    Fruit features (Brassicaceae)
    NA
    Fruit length
    3–4.5 mm
    Fruit locules
    three
    Fruit type (general)
    • the fruit is dry and splits open when ripe
    • the fruit is dry but does not split 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
    4–5 mm
    Legumes (Fabaceae)
    NA
    Mericarp length
    3–3.5 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 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
    the fruit is not flattened
    Schizocarpic fruit segments
    0–3
    Seed length
    2–2.6 mm
    Seed number
    3
    Seed relative length
    the seed is longer than it is wide
    Seed surface
    the seed is smooth or without clear markings
    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 milky and opaque, and may be white or colored
    Sap color
    the sap is white

  • 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
    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
    Bracteoles
    the plant has bracteoles between the primary bracts and the flowers
    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 bracts
    the flower has one or more bracts associated with it
    Hairs on underside of leaf
    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 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
    opposite: there are two leaves per node along the stem
    Leaf blade base
    the leaf has a distinct leaf stalk (petiole)
    Leaf blade base symmetry
    the leaf blade base is asymmetrical
    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
    NA
    Leaf blade length
    4–12.5 mm
    Leaf blade primary vein pattern
    the secondary veins branch off at intervals from the primary vein
    Leaf blade shape
    • the leaf blade is linear (very narrow with more or less parallel sides)
    • the leaf blade is oblong (rectangular but with rounded ends)
    Leaf blade surface colors
    the upper side of the leaf blade is relatively uniform in color
    Leaf blade texture
    the leaf blade has a fleshy or spongy texture
    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
    1–3 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
    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
    1.5 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 obtuse (bluntly pointed)
    Leaf type
    the leaves are simple (lobed or unlobed but not separated into leaflets)
    Leaf types
    NA
    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 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
    Stipule fused to leaf stalk
    the stipules are not fused to the petioles
    Stipule length
    1 mm
    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
    • Rhode Island
    Specific habitat
    • dunes
    • sea beaches

  • Stem, shoot, branch

    Branched tendrils
    NA
    Direction of stem hairs
    NA
    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 no hairs between the nodes
    Hairs between stem nodes
    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
    Length of hairs between stem nodes
    0 mm
    Plant height
    Up to 18 cm
    Stem hair distribution
    NA
    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 succulent
    Tendril origin
    NA
    Tendrils
    the plant does not have tendrils
    Wings on stem
    the stem does not have wings on it

Wetland status

Occurs only in non-wetlands. (Wetland indicator code: UPL)

New England distribution and conservation status

Distribution

Connecticut
absent
Maine
absent
Massachusetts
absent
New Hampshire
absent
Rhode Island
absent
Vermont
absent

Conservation status

Exact status definitions can vary from state to state. For details, please check with your state.

Massachusetts
unranked (S-rank: SNR)
New Hampshire
historical (S-rank: SH), -- (code: --)

Native to North America?

Yes

Synonyms

  • Chamaesyce polygonifolia (L.) Small

Family

Euphorbiaceae

Genus

Euphorbia

Help

From the dichotomous key of Flora Novae Angliae

14.  Euphorbia polygonifolia L. N

seaside sandmat. Chamaesyce polygonifolia (L.) Small • CT, MA, ME, NH, RI; coastal sites. Sea beaches, dunes, sandy areas near the Atlantic coast.