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- Ranunculus
- Ranunculus rhomboideus
Ranunculus rhomboideus — prairie crowfoot
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Facts
Prairie crowfoot is native to the priaries of north-central North America, and introduced elsewhere, including in New England, where it has been collected in Massachusetts and Rhode Island.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
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
- 
                                
                                    - Massachusetts
- Rhode Island
 
- Flower petal color
- yellow
- Leaf type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
- Leaf arrangement
- alternate: there is one leaf 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)
- Number of sepals, petals or tepals
- there are five petals, sepals, or tepals in the flower
- Fusion of sepals and petals
- both the petals and sepals are separate and not fused
- Stamen number
- 13 or more
- Fruit type (general)
- the fruit is dry but does not split open when ripe
- Fruit length
- 1.8–2.2 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- 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 are two or more ways to evenly divide the calyx (the calyx is radially symmetrical)
 - Carpels fused
- the carpel is solitary or (if 2 or more) the carpels are not fused to one another
 - Cleistogamous flowers
- there are no cleistogamous flowers on the plan
 - 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 lacks a hypanthium
 - 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 style is narrow at the tip and unbranched
 - Fused stamen clusters
- NA
 - Fusion of sepals and petals
- both the petals and sepals are separate and not fused
 - 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
- 6 or more
 - Number of sepals, petals or tepals
- there are five 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 folds or pleats
- the petals of the flower do not have folds or plaits
 - Petal hairs (Viola)
- NA
 - Petal number
- 5
 - 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
- 13 or more
 - Stamen position relative to petals
- NA
 - 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
- the achenes are perpendicular to the plane of the perianth (vertical)
 - Achene surface (Polygonum)
- NA
 - Achene type
- the fruit is an achene (dry, indehiscent, and usually one-seeded)
 - Berry color
- NA
 - Capsule color (Viola)
- NA
 - Capsule ribs
- NA
 - Capsule splitting
- NA
 - Fruit (pyxis) dehiscence
- NA
 - Fruit features (Brassicaceae)
- NA
 - Fruit length
- 1.8–2.2 mm
 - Fruit locules
- one
 - Fruit type (general)
- the fruit is dry but does not split open when ripe
 - Fruit type (specific)
- the fruit is an achene (dry, usually one-seeded, does not separate or split open at maturity)
 - Legumes (Fabaceae)
- NA
 - Mericarp length
- 0 mm
 - Mericarp segment shape (Desmodium)
- NA
 - Other markings on berry
- NA
 - Placenta arrangement
- 
                                
                                    - marginal
- the plant has basal placentation, where one or a few ovules develop at the base of a simple or compound ovary
 
 - Rows of seeds in fruit (Brassicaceae)
- NA
 - Schizocarpic fruit compression
- NA
 - Schizocarpic fruit segments
- 0
 - 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 more than two years
 - 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
 
- 
                        Leaves- Bracteole number (Apiaceae)
- 0
 - Bracts in plantain (Plantago)
- NA
 - Final leaf segment length (compound lvs only)
- At least 0 mm
 - Final leaf segment length to width ratio (compound lvs only)
- At least 0
 - Hairs on underside of leaf
- the underside of the leaf is fuzzy or hairy
 - Leaf arrangement
- alternate: there is one leaf per node along the stem
 - Leaf blade base
- 
                                
                                    - the leaf has a distinct leaf stalk (petiole)
- the leaf has no stalk
 
 - 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 has teeth
 - Leaf blade length
- 11–53 mm
 - Leaf blade shape
- 
                                
                                    - the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- the leaf blade is rhombic (roughly diamond-shaped)
 
 - 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 type
- the leaves are simple (lobed or unlobed but not separated into leaflets)
 - 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
- 0
 - Leaflet petiolules
- NA
 - Leaves per node
- there is one leaf 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
- there are no stipules on the plant
 
- 
                        Place- Habitat
- terrestrial
 - New England state
- 
                                
                                    - Massachusetts
- Rhode Island
 
 - 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
 - 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
- 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
 - Plant height
- 10–20 cm
 - Tendril origin
- NA
 - Tendrils
- the plant does not have tendrils
 
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- 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)
From Flora Novae Angliae dichotomous key
18. Ranunculus rhomboideus Goldie E
prairie crowfoot. MA, RI. Fields, roadsides, waste areas.
Native to North America?
No
![Leaves: Ranunculus rhomboideus. ~ By Curtis Bjork. ~ Copyright © 2025 Curtis Bjork. ~ crbjork[at]gmail.com ~ E-Flora BC - www.geog.ubc.ca/biodiversity/eflora/](https://newfs.s3.amazonaws.com/taxon-images-239x239/Ranunculaceae/ranunculus-rhomboideus-le-cbjork.jpg) 
                         
                         
                         
                         
                         
                         
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