Spiraea thunbergii — Thunberg's meadowsweet
![Flowers: Spiraea thunbergii. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Rosaceae/spiraea-thunbergii-fl-ahaines.jpg)
![Plant form: Spiraea thunbergii. ~ By Arthur Haines. ~ Copyright © 2024 Arthur Haines. ~ arthur.d.haines[at]gmail.com](https://newfs.s3.amazonaws.com/taxon-images-1000s1000/Rosaceae/spiraea-thunbergii-ha-ahaines.jpg)
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Facts
This shrub is native to Asia. It was brought to New England for horticulture and has escaped the cultivated setting.
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.
enlargeCharacteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Growth form
- the plant is a shrub (i.e., a woody plant with several stems growing from the base)
- Leaf type
- the leaf blade is simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaves per node
- there is one leaf per node along the stem
- Leaf blade edges
- the edge of the leaf blade has teeth
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- armature on plant
- the plant does not have spines, prickles, or thorns
- Leaf blade length
- 20–40 mm
- Leaf blade width
- 3–7 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Bark texture
- the bark of an adult plant is thin and smooth
- Twig winter color
-
- brown
- red
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
-
Buds or leaf scars
- Bud scale number
- there are three or more scales on the winter bud, and they overlap like shingles, with one edge covered and the other edge exposed
- Bud scar shape (Fraxinus)
- NA
- Collateral buds
- there are no collateral buds on the sides of the branches
- Superposed buds
- there are no superposed buds on the branch
- Winter bud shape
- the winter buds are ovoid (egg-shaped)
-
Flowers
- Carpels fused
- the carpel is solitary or (if 2 or more) the carpels are not fused to one another
- Enlarged sterile flowers
- there are no enlarged sterile flowers on the plant
- Flower petal color
- white
- Flower symmetry
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- Hairs on ovary (Amelanchier)
- NA
- Hypanthium present
- the flower has a hypanthium
- Inflorescence type
-
- the inflorescence is a corymb (with long lower branches and shorter upper branches, giving it a more or less flat-topped look)
- the inflorescence is an umbel (with an axis so short it appears the flowers all originate from the same point)
- Number of pistils
- 5
- 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 appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal fusion
- the perianth parts are separate
- Sepal cilia (Ilex)
- NA
- Stamen number
- 13 or more
-
Fruits or seeds
- Berry color
- NA
- Fruit tissue origin
- there are no flower parts that form part of the fruit
- Fruit type (general)
- the fruit is dry and splits open when ripe
- Fruit type (specific)
- the fruit is a follicle (has one ovary that splits along one side to release the seeds)
- Nut with spines (Fagaceae)
- NA
- Wings on fruit
- there are no wings on the fruit
-
Glands or sap
- Sap color
- the sap is clear and watery
- Stalked glands on fruit (Rosa)
- NA
-
Growth form
- Growth form
- the plant is a shrub (i.e., a woody plant with several stems growing from the base)
-
Leaves
- Hairs on upper side of leaf blade
- the upper side of the leaf is not hairy, or has very few hairs
- 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 edges (Acer)
- NA
- Leaf blade flatness
- the leaf is flat (planar) at the edges
- Leaf blade hairs
- NA
- Leaf blade length
- 20–40 mm
- Leaf blade scales
- there are no scales on the leaf blades
- Leaf blade shape
- the leaf blade is lanceolate (lance-shaped; widest below the middle and tapering at both ends)
- Leaf blade translucent dots
- there are no translucent dots on the leaf blade
- Leaf blade width
- 3–7 mm
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf lobe tips (Quercus)
- NA
- Leaf midrib glands
- the midrib of the leaf blade lacks glands on the upper surface
- Leaf stalk
- the leaves have leaf stalks
- Leaf teeth
- the leaf blade margin is serrate (with forward-pointing) or dentate (with outward-pointing) with medium-sized to coarse teeth
- Leaf teeth hairs (Carya)
- NA
- Leaf type
- the leaf blade is simple (i.e., lobed or unlobed but not separated into leaflets)
- Leaves per node
- there is one leaf per node along the stem
- Specific leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Scent
- Plant odor
- the plant does not have much of an odor, or it has an unpleasant or repellant odor
-
Stem, shoot, branch
- Aerial roots
- the plant has no aerial roots
- Bark texture
- the bark of an adult plant is thin and smooth
- Branch brittleness (willows only)
- NA
- Branch cross-section
- the branch is circular in cross-section, or it has five or more sides, so that there are no sharp angles
- First-year cane (Rubus)
- NA
- Twig papillae (Vaccinium species only)
- NA
- Twig winter color
-
- brown
- red
- Wings on branch
- the branch does not have wings on it
- armature on plant
- the plant does not have spines, prickles, or thorns
Wetland status
Not classified
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
5. Spiraea thunbergii Sieb. ex Blume E
Thunberg’s meadowsweet. CT, ME; also reported from MA by Magee and Ahles (1999), but specimens are unknown. Fields, roadsides, waste areas, abandoned homesteads.
Native to North America?
No
Sometimes confused with
- Spiraea chamaedryfolia:
- inflorescences except sometimes the uppermost borne on a peduncle, with 5–12 flowers, and petioles 4–7 mm long (vs. S. thunbergii, with inflorescences sessile, with 3–7 flowers, and petioles 1–4 mm long).
- Spiraea prunifolia:
- leaf blades ovate to oblong-lanceolate, pubescent on the abaxial surface, and pedicels 10–24 mm long, pubescent (vs. S. thunbergii, with leaf blades narrow-lanceolate, glabrous on the abaxial surface, and pedicels 6–10 mm long, glabrous).