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- Fabaceae
- Glycine
- Glycine max
Glycine max — soybean
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Facts
Soybean is cultivated throughout the temperate and tropical regions, and is one of the most significant sources of protein and oils globally. It has escaped cultivation to become weedy in some parts of eastern North America, although it is rarely encountered in New England.
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
- Flower petal color
-
- blue to purple
- white
- Leaf type
- the leaves are compound (made up of two or more discrete leaflets
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Number of sepals, petals or tepals
-
- there are five petals, sepals, or tepals in the flower
- there are four petals, sepals, or tepals in the flower
- Stamen number
- 10
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit length
- 30–70 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 is only one way to evenly divide the calyx (the calyx is bilaterally symmetrical)
- Carpels fused
-
- NA
- 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 a hypanthium
- Flower number
- 1–8
- Flower orientation
-
- the flower bends downwards or hangs downwards
- the flower points upwards or is angled outwards
- Flower petal color
-
- blue to purple
- white
- Flower reproductive parts
- the flower has both pollen- and seed-producing parts
- Flower symmetry
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Flowers sunken into stem
- no
- Fused stamen clusters
- there are two clusters of fused stamens
- Hairs on inflorescence
- the axis of the inflorescence has hairs entirely without glands
- Horns in hoods (Asclepias)
- NA
- Hypanthium
- the flower has a hypanthium
- Inflorescence length
- 10–20 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
- Length of peduncle
- 10–35 mm
- Nectar spur
- the flower has no nectar spurs
- Number of carpels
- 1
- Number of pistils
- 1
- Number of sepals, petals or tepals
-
- there are five petals, sepals, or tepals in the flower
- there are four 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
-
- blue to purple
- white
- 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 arranged in a cycle with edges overlapping like roof shingles (imbricate)
- Petal folds or pleats
-
- the petals of the flower do not have folds or plaits
- the petals of the flower have folds or plaits on them
- Petal hairs (Viola)
- NA
- Petal length
- 5–7 mm
- Petal length relative to sepals
-
- the petals are about equal in length to the sepals
- the petals are longer than the sepals
- Petal number
- 5
- Petal shape
-
- the petal outline is obovate (roughly egg-shaped, but with the widest point above the middle of the leaf blade)
- the petal outline is orbicular (roughly circular, as wide as long)
- Petal tip shape
- the petal tip is rounded
- Petal tips (Cuscuta)
- NA
- Raceme attachment (Veronica)
- NA
- 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 length
- 4–6 mm
- Sepal number
- 5
- Sepal orientation
- the sepals are slightly curved outwards from the corolla
- Sepal relative length
-
- the sepal lobes are approximately the same length as the fused portion
- the sepal lobes are shorter than the fused portion
- Sepal shape
- the sepal outline is lanceolate (lance-shaped; narrow, gradually tapering from the base to the tip)
- Sepal tip shape
-
- the sepal tip is acuminate (tapers to a very narrow point)
- the sepal tip is acute (is sharply pointed)
- Sepal uniformity
- one or more of the sepals is much narrower or shorter than the others
- Sepals fused only to sepals
- the sepals are fused to each other (not other flower parts), at least near their bases
- Stamen morphology
- the stamens within each cycle are the same
- Stamen number
- 10
- Stamens fused
- the stamens are attached to one another at or near their bases
- 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
- Capsule splitting
-
- NA
- the capsule splits by two main valves, teeth or pores
- Fruit (pyxis) dehiscence
- NA
- Fruit cross-section
- the fruit is round in cross-section
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 30–70 mm
- Fruit length relative to sepals
- the fruit is longer than its associated sepals
- Fruit locules
- one
- Fruit shape
- the fruit is obloid (longer than wide and with rounded ends)
- 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 legume (a fruit that splits into two valves, but only has a single carpel; think of a pea pod)
- Fruit width
- 10–15 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)
- the legume has none of the mentioned special features
- 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 parietal placentation, where ovules develop on the wall or slight outgrowths of the wall forming broken partitions within a compound ovary
- Rows of seeds in fruit (Brassicaceae)
- NA
- Schizocarpic fruit compression
- NA
- Schizocarpic fruit segments
- 0
- Seed length
- 10 mm
- Seed number
- 2–5
- Seed surface
- the seed is smooth or without clear markings
- 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 a vine (it cannot support its own weight)
- 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
-
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)
- 70–120 mm
- Final leaf segment width (compound lvs only)
- Up to 1.5 mm
- Floral bracts
- the flower has one or more bracts associated with it
- Hairs on leaf stalk
- the petiole has hairs on it
- Leaf arrangement
- alternate: there is one leaf 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
- the base of the leaf blade is rounded
- Leaf blade base symmetry
- the leaf blade base is symmetrical
- 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 primary vein pattern
- the secondary veins branch off at intervals from the primary vein
- Leaf blade shape
-
- the leaf blade is elliptic (widest near the middle and tapering at both ends)
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade texture
- the leaf blade is scarious (thin and dry like paper) or membranaceous (thin and flexible and almost translucent like a membrane)
- 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 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 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
- 20–200 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 acute (sharply pointed)
- the tip of the leaf blade is rounded, with no point
- Leaf type
- the leaves are compound (made up of two or more discrete leaflets
- Leaf types
- There is a gradual change in appearance of the leaves from the base (or near the base) of the plant to those from further up on the stem, with leaves progressively changing as one moves higher on the stem (often becoming shorter, or less toothed/lobed, and/or with shorter petioles).
- Leaf variation
- the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem
- Leaflet number
- 3
- Leaflet petiolules
- the leaflets of the compound leaf have petiolules
- Leaves per node
- there is one leaf per node along the stem
- Pinnately compound leaf type
- the pinnately compound leaves have a terminal leaflet (and usually have an odd number of leaflets per axis)
- Specific leaf type
- the leaf has a row of two or more lobes on each side of the central axis
- Stipels
- the petiolules have stipels at their bases
- Stipule features
- NA
- Stipule length
- 3–7 mm
- Stipule shape
- the stipules are ovate (widest below the middle and broadly tapering at both ends)
- Stipules
- the plant has stipules
- Teeth per side of leaf blade
- 0
-
Place
- Habitat
- terrestrial
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Branched tendrils
- NA
- Direction of stem hairs
- 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
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Plant height
- 30–90 cm
- Stem hair distribution
- the hairs on the stem are distributed more of less uniformly
- Stem orientation
- the stems are upright or angled outwards
- Stem spacing
- the plant is solitary, or a few plants are growing together
- 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
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- present
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. Glycine max (L.) Merr. E
soybean. Phaseolus max L. • MA, VT. Fields, roadsides, areas of cultivation.