Your help is appreciated. We depend on donations to help keep this site free and up to date for you. Can you please help us?

Donate

Native Plant Trust: Go Botany Discover thousands of New England plants

Isotrema tomentosum — woolly Dutchman's pipe

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

Facts

Woolly Dutchman's pipe, as both its common and species names suggest, is covered with woolly hairs on its stems and leaf undersides. Native to the southeastern U. S., this species is considered introduced in New England where it inhabits old home sites and roadsides. Unlike large-leaved Dutchman's pipe (Isotrema macrophyllum) which scrambles over rocks, this species tends to prefer river banks and other moist habitats.

Habitat

Anthropogenic (man-made or disturbed habitats)

New England distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America distribution

Adapted from BONAP data

enlarge

Characteristics

Habitat
terrestrial
New England state
Massachusetts
Growth form
the plant is a liana (i.e., a woody plant with a vine-like growth form)
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 no teeth or lobes
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
90–200 mm
Leaf blade width
80–150 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 ridged or plated
Twig winter color
  • green
  • white
Bud scale number
there are two scales on the winter bud, and their edges meet
Show all characteristics
  • Buds or leaf scars

    Bud scale number
    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 superposed buds above the main (terminal) bud
  • 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
    NA
    Flower symmetry
    there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
    Hairs on ovary (Amelanchier)
    NA
    Hypanthium present
    the flower does not have a hypanthium
    Inflorescence hairs
    there are hairs on some part of 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 has only one flower on it
    Number of pistils
    1
    Ovary position
    the ovary is below the point of petal and/or sepal attachment
    Petal and sepal arrangement
    the flower includes only one cycle of petals or sepals
    Petal appearance
    NA
    Petal fusion
    • NA
    • the perianth parts are fused to form a tube, cup, or bell shape
    Sepal appearance
    the sepals resemble petals 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 fused to each other (not other flower parts), at least near their bases
    Stamen number
    6
    Stamen position relative to petals
    NA
  • 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 capsule (splits along two or more seams, apical teeth or pores when dry, to release two or more 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 liana (i.e., a woody plant with a vine-like growth form)
  • Leaves

    Hairs on underside of leaf blade
    the underside of the leaf has hairs on it
    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)
    Leaf blade base symmetry
    the leaf blade base is symmetrical
    Leaf blade bloom
    the underside of the leaf has no noticeable bloom
    Leaf blade edges
    the edge of the leaf blade has no teeth or lobes
    Leaf blade edges (Acer)
    NA
    Leaf blade flatness
    the leaf is flat (planar) at the edges
    Leaf blade hairs
    the hairs on the leaf blade are different from the choices given
    Leaf blade length
    90–200 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 coriaceous (has a firm, leathery texture)
    • the leaf blade is membranaceous (thin, flexible, almost translucent)
    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 blade width
    80–150 mm
    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 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 edge of the leaf blade is entire (has no teeth or lobes)
    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
    there are no stipules on the plant, or they fall off as the leaf expands
  • Place

    Habitat
    terrestrial
    New England state
    Massachusetts
    Specific habitat
    man-made or disturbed habitats
  • Scent

    Plant odor
    the plant has a pleasantly aromatic odor
  • Stem, shoot, branch

    Aerial roots
    the plant has no aerial roots
    Bark texture
    the bark of an adult plant is ridged or plated
    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 no lenticels on the twigs, or they are very hard to see
    Pith shape
    the outline of the pith in a twig is roughly round
    Pith type
    the pith inside the twig is chambered (there are hollow sections with walls between them)
    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 hairs, but the hairs do not have glands
    Twig papillae (Vaccinium species only)
    NA
    Twig scales
    there are no scales on the twig surface
    Twig winter color
    • green
    • white
    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

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

In New England

Distribution

Connecticut
absent
Maine
absent
Massachusetts
present
New Hampshire
absent
Rhode Island
absent
Vermont
absent

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

2.  Isotrema tomentosum (Sims) Huber E

woolly Dutchman’s pipe. Aristolochia tomentosa Sims • MA. Roadsides and abandoned 
lots, near areas of human habitation. The report of this species in CT and VT by Kartesz (1999) was erroneous.

Native to North America?

Yes and no (some introduced)

Sometimes confused with

Isotrema macrophyllum:
stems and abaxial leaf surface glabrous to puberulent and peduncle with a bract near the middle (vs. I. tomentosum, with stems and abaxial leaf surface tomentose and the peduncle without a bract).

Synonyms

  • Aristolochia tomentosa Sims

Genus

Isotrema