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- Rubiaceae
- Houstonia
- Houstonia purpurea
Houstonia purpurea — large bluet
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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.
Facts
Large bluet inhabits dry fields, meadows and clearings in four of the six New England states. It closely resembles a much less common species, H. longifolia, which is considered very rare in a number of states. To tell them apart, look for leaves along the stem that are wider (5-12 mm wide) and rounded at the base, with sepals that are 3-6 mm (longer) when the flowers are in bloom.
Habitat
Forest edges, meadows and fields
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- Vermont
- Flower petal color
-
- blue to purple
- 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 length
- 0.25–0.35 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
-
- blue to purple
- 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 style is lobed at the tip, and unbranched
- Fused stamen clusters
- NA
- 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 folds or pleats
- the petals of the flower do not have folds or plaits
- 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 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
- Capsule color (Viola)
- NA
- Capsule splitting
- the capsule splits by two main valves, teeth or pores
- Fruit (pyxis) dehiscence
- NA
- Fruit features (Brassicaceae)
- NA
- Fruit length
- 0.25–0.35 mm
- Fruit locules
- two
- 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)
- 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 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
- 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 no stalk
- Leaf blade base shape
-
- the base of the leaf blade is cordate (heart-shaped, has rounded lobes at the base)
- the base of the leaf blade is rounded
- Leaf blade edges
- the edge of the leaf blade is entire (has no teeth or lobes)
- Leaf blade length
- 20–50 mm
- Leaf blade shape
-
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- 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 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
- Stipels
- NA
- Stipule features
- NA
- Stipules
- the plant has stipules
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- Vermont
- Specific habitat
-
- edges of forests
- 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 roughly square
- Hair between stem nodes
-
- the stem has hairs between the nodes
- the stem has no hairs between the nodes
- Leaves on stem
- there is at least one full leaf above the base of the flowering stem
- Plant height
- 15–50 cm
- Tendril origin
- NA
- Tendrils
- the plant does not have tendrils
Wetland status
Not classified
New England distribution and conservation status
Distribution
- Connecticut
- present
- Maine
- present
- 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.
var. purpurea
- Massachusetts
- unranked (S-rank: SNR)
Native to North America?
Yes
Sometimes confused with
Family
Genus
From the dichotomous key of Flora Novae Angliae
3. Houstonia purpurea L. var. calycosa Gray E
large bluet. Hedyotis lanceolata Poir.; H. purpurea (L.) Torr. & Gray var. calycosa (Gray) Fosberg; Houstonia calycosa (Gray) C. Mohr; H. lanceolata (Poir.) Britt. • CT, MA, ME, VT. Dry fields, meadows, and clearings.