- You are here:
- Dichotomous Key
- Euphorbiaceae
- Mercurialis
- Mercurialis annua
Mercurialis annua — annual mercury
Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.
Facts
Annual mercury is native to Europe and introduced nearly worldwide. Its North American distribution is scattered, and in New England it has been collected only in Massachusetts and Maine. It may have been introduced in ships' ballast, as early collections were from ballast dump sites.
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
- Leaf type
- the leaves are simple (i.e., 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 has teeth
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Fruit type (general)
-
- the fruit is dry and splits open when ripe
- the fruit is dry but does not split open when ripe
-
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 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)
- 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 symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Flowers sunken into stem
- no
- Fused stamen clusters
- NA
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower does not have a hypanthium
- Inner tepals (Rumex)
- NA
- Nectar spur
- the flower has no nectar spurs
- 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 appearance
- NA
- Petal hairs (Viola)
- NA
- Petal number
- 0
- Petal tips (Cuscuta)
- NA
- 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
- anything
- 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 surface (Polygonum)
- NA
- Achene type
- NA
- Berry color
- NA
- Capsule color (Viola)
- NA
- Fruit (pyxis) dehiscence
- NA
- Fruit beak length
- anything
- Fruit features (Brassicaceae)
- NA
- 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
- 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
- Schizocarpic fruit segments
- anything
- 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
- 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 to width ratio (compound lvs only)
- 0
- Final leaf segment width (compound lvs only)
- 0 mm
- Leaf arrangement
- opposite: there are two leaves per node along the stem
- Leaf blade edges
- the edge of the leaf blade has teeth
- 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 leaf blade margin has forward-pointing teeth
- the leaf blade margin has rounded teeth
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaflet petiolules
- NA
- Leaves per node
- there are two leaves per node along the stem
- Pinnately compound leaf type
- NA
- Stipule features
- NA
- Stipules
- the plant has stipules
-
Place
- Habitat
- terrestrial
- Specific habitat
- man-made or disturbed habitats
-
Scent
- Plant odor
- the plant does not have much of a smell
-
Stem, shoot, branch
- Branched tendrils
- NA
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- present
- 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
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
1. Mercurialis annua L. E
annual mercury. MA, ME. Yards, roadsides, ballast, waste areas.