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- Tilia
- Tilia americana
Tilia americana — American linden
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Facts
American linden or basswood is the only tall tree among the New England members of the mallow family (Malvaceae). And a grand tree it is, one of the most commonly planted, statuesque street trees. Young leaves of this species have star-shaped (stellate) hairs on the upper surfaces. The leaves of Tilia species have rounded bases that are asymmetrical on either side of the petiole. Tilia wood is light and easy to work; it is made into yardsticks, crates, parts for musical instruments, cabinets and pulp. The inner bark is very fibrous and excellent for weaving baskets and rope. Trunks often develop cavities, which become nesting sites for woodpeckers and other animals. The flowers are very fragrant and their nectar attracts bees that convert it to good honey.
Habitat
Floodplain (river or stream floodplains), forests
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
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Growth form
- the plant is a tree
- 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
- 70–200 mm
- Leaf stalk
- the leaves have leaf stalks
- Fruit type (general)
-
- the fruit is dry but does not split open when ripe
- the fruit is fleshy
- Bark texture
-
- the bark of an adult plant is ridged or plated
- the bark of an adult plant is thin and smooth
- Twig winter color
-
- brown
- gray
- 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
- there are two scales on the winter bud, and their edges meet
-
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
- there are two scales on the winter bud, and their edges meet
- Bud scar shape (Fraxinus)
- NA
- Collateral buds
- there are no collateral buds on the sides of the branches
- Leaf scar arrangement
- there is one leaf scar per node on the stem or twig
- Superposed buds
- there are no superposed buds on the branch
- Terminal bud
- there is no terminal bud on the branch
- Winter bud stalks
- the winter buds have no stalks
-
Flowers
- Carpels fused
- the carpels are 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 does not have a hypanthium
- Inflorescence hairs
- there are no hairs on the inflorescence
- Inflorescence type
-
- the flowers grow out of the axil (point where a branch or leaf is attached to the main stem)
- the inflorescence is a dichasial cyme (an axis with a terminal flower, below it a pair of branches, each with a terminal flower, these branches may in turn each have a pair of branches and so on)
- Number of pistils
- 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 appearance
- the petals are thin and delicate, and pigmented (colored other than green or brown)
- Petal fusion
- the perianth parts are separate
- Sepal appearance
- the sepals resemble leaves in color and texture
- Sepal cilia (Ilex)
- NA
- Sepal tip glands
- there are no glands at the tips of the sepal lobes
- Sepals fused only to sepals
- the sepals are separate from one another
- Stamen number
-
- 10
- 11
- 12
- 13 or more
- Stamen position relative to petals
- the stamens are lined up with the petals (antepetalous)
- Stamens fused
- the stamens are fused to one another at or near their bases
-
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 but does not split open when ripe
- the fruit is fleshy
- Fruit type (specific)
- the fruit is a drupe (fleshy, with a firm inner ovary wall that encloses a single seed)
- 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 tree
-
Leaves
- Hairs on underside of leaf blade
-
- the underside of the leaf has hairs on it
- the underside of the leaf has no hairs
- 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 cordate (heart-shaped, with rounded lobes)
- the base of the leaf blade is truncate (ends abruptly in a more or less straight line as though cut off)
- Leaf blade base symmetry
- the leaf blade base is asymmetrical
- Leaf blade bloom
- the underside of the leaf has no noticeable bloom
- 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
- at least some of the hairs on the leaf blade are branched
- Leaf blade length
- 70–200 mm
- Leaf blade scales
- there are no scales on the leaf blades
- Leaf blade shape
-
- the leaf blade is orbicular (roughly circular, as wide as long)
- the leaf blade is ovate (widest below the middle and broadly tapering at both ends)
- Leaf blade texture
- the leaf blade is herbaceous (has a leafy texture)
- Leaf blade translucent dots
- there are no translucent dots on the leaf blade
- Leaf blade vein pattern
- the main veins of the leaf blade are palmate (radiate out from the base, like a hand)
- Leaf blade veins
- the leaf blade has three or more main veins running from the base (or near the base) towards the tip
- Leaf duration
- the leaves drop off in winter (or they wither but persist on the plant)
- Leaf form
- the plant is broad-leaved (with broadly flattened leaf blades)
- 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 stalk attachment to leaf
- the petiole attaches at the basal margin of the leaf blade
- Leaf stalk nectaries
- there are no nectaries on the leaf stalk
- Leaf stalk shape
- the leaf stalk is not flattened
- 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
- Stipules
- the plant has stipules
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- forests
- river or stream floodplains
-
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 ridged or plated
- 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
- Lenticels on twigs
- there are clearly lenticels on the twigs
- Pith shape
- the outline of the pith in a twig is roughly round
- Short shoots
- there are no peg- or knob-like shoots present
- Twig bloom
- there is no bloom on the twig
- Twig hairs
- the twigs have few or no hairs on them
- Twig papillae (Vaccinium species only)
- NA
- Twig scales
- there are no scales on the twig surface
- Twig winter color
-
- brown
- gray
- 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
Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- unranked (S-rank: SNR)
var. americana
- Massachusetts
- widespread (S-rank: S5)
var. heterophylla
- Massachusetts
- not applicable (S-rank: SNA)
Subspecies and varieties
Tilia americana L. var. americana is native and known from CT, MA, ME, NH, RI, VT.T. americana var. heterophylla (Vent.) Loud. is non-native and known from MA, ME.
From Flora Novae Angliae dichotomous key
1. Tilia americana L. n
American linden. 1a. Tilia americana L. var. neglecta (Spach) Fosberg; T. glabra Vent.; T. neglecta Spach; 1b. Tilia heterophylla Vent.; T. heterophylla Vent. var. michauxii (Nutt.) Sarg.; T. michauxii Nutt.; T. monticola Sarg. • CT, MA, ME, NH, RI, VT. Mesic, deciduous forests, including rich and riparian types. Tilia neglecta is a phase of T. americana var. americana in which the abaxial surface of the leaf blades has a sparse covering of stellate hairs; however, other features (e.g., peduncle and pedicel indumentum) are as in var. americana.
1a. Leaf blades pubescent with bulbous glands, slender hairs, and sometimes scattered stellate hairs on the abaxial surface; peduncles and pedicels glabrous or sparsely puberulent in fruit … 1a. T. americana var. americana
1b. Leaf blades densely pubescent with stellate hairs on the abaxial surface (rarely becoming puberulent in age, but stellate hairs persisting along the major veins); peduncles and pedicels pubescent with stellate hairs in fruit … 1b. T. americana var. heterophylla (Vent.) Loud.
Variety americana is native and known from CT, MA, ME, NH, RI, VT. Variety heterophylla is non-native and known from MA, ME.
Native to North America?
Yes
Sometimes confused with
- Tilia cordata:
- leaf blades mostly 3-9 cm long and fruit 4.5-6.6 mm long (vs. T. americana, with leaf blades 7-20 cm long and fruit mostly 6-8 mm long).
- Tilia petiolaris:
- petioles more than 50% as long as the blade, pubescent, mature branchlets usually at least sparsely pubescent, and fruit pericarp verrucose and 5-grooved (vs. T. americana, with petioles less than 50% as long as the blade, glabrous, mature branchlets glabrous, and fruit pericarp +/- smooth).
Synonyms
- Tilia americana var. neglecta (Spach) Fosberg
- Tilia glabra Vent.
- Tilia neglecta Spach