• You are here:
• Full Key
• All other flowering non-woody plants
• All other herbaceous, flowering dicots
• Mentzelia oligosperma

Mentzelia oligosperma — stickleaf mentzelia

Facts

Stickleaf mentzelia is native to central and southern North America, and has not been found elsewhere, except in Massachusetts, in the waste area of a nineteenth-century wool-carding factory. The leaves are covered with hooked hairs and cling tightly to clothing or sheeps' wool.

Habitat

Anthropogenic (man-made or disturbed habitats)

Characteristics

• 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)

  Corona lobe length

  0 mm

  Epicalyx

  the flower does not have an epicalyx

  Epicalyx number of parts

  0

  Flower description

  the flower has an inferior ovary, with or without a hypanthium

  Flower petal color

  yellow

  Flower reproductive parts

  the flower has both pollen- and seed-producing parts

  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

  Fusion of sepals and petals

  both the petals and sepals are separate and not fused

  Horns in hoods (Asclepias)

  NA

  Hypanthium

  the flower has a hypanthium

  Inner tepals (Rumex)

  NA

  Nectar spur

  the flower has no nectar spurs

  Number of pistils

  1

  Number of sepals, petals or tepals

  there are five petals, sepals, or tepals in the flower

  Number of styles

  1

  Ovary position

  the ovary is below 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

  yellow

  Petal appearance

  the petals are thin and delicate, and pigmented (colored other than green or brown)

  Petal hairs (Viola)

  NA

  Petal number

  5

  Petal tips (Cuscuta)

  NA

  Reproductive system

  NA

  Sepal appendages

  the sepals do not have appendages on them

  Sepal appendages (Oenothera)

  NA

  Sepal number

  5

  Stamen attachment

  the stamens are attached at or near the bases of the petals or tepals

  Stamen number

  13 or more

  Stamen position relative to petals

  NA

  Stamens fused

  the stamens are not attached to one another

  Stigma position

  the stigmas are positioned at the tip of the style

  Style petal-like

  the styles are not petal-like

  Umbel flower reproductive parts

  NA

• Fruits or seeds

  Achene surface (Polygonum)

  NA

  Capsule color (Viola)

  NA

  Fruit (pyxis) dehiscence

  NA

  Fruit features (Brassicaceae)

  NA

  Fruit length

  10 mm

  Fruit locules

  one

  Fruit shape

  the fruit is roughly cylindrical (with parallel sides that do not taper, and flat across the top and bottom)

  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)

  Legumes (Fabaceae)

  NA

  Mericarp length

  anything

  Mericarp segment shape (Desmodium)

  NA

  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

  Septum in fruit (Brassicaceae)

  NA

  Wings on fruit

  the fruit does not have wings on it

• 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 subshrub (small shrub with partially herbaceous stems)
  • the plant is an herb (it has self-supporting stems)

  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

  there are spines on the plant

• Leaves

  Bracteole number (Apiaceae)

  0

  Bracts in plantain (Plantago)

  NA

  Hairs on underside of leaf

  the underside of the leaf is fuzzy or hairy

  Hairs on upper side of leaf

  the upper side of the leaf is fuzzy or hairy

  Leaf arrangement

  alternate: there is one leaf per node along the stem

  Leaf blade base

  • the leaf has a distinct leaf stalk (petiole)
  • the leaf has no stalk

  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 edges

  • the edge of the leaf blade has lobes, or it has both teeth and lobes
  • the edge of the leaf blade has teeth

  Leaf blade length

  30–60 mm

  Leaf blade shape

  • 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 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 stalk

  • the leaves have leaf stalks
  • the leaves have no leaf stalks, but attach directly to the stem

  Leaf teeth and lobes

  • the leaf blade margin has forward-pointing teeth
  • the leaf blade margin is wavy, but does not have teeth

  Leaf type

  the leaves are simple (lobed or unlobed but not separated into leaflets)

  Leaf variation

  the leaves are nearly similar in size, prominence of teeth, and length of stalks throughout the stem

  Leaves per node

  there is one leaf per node along the stem

  Specific leaf type

  the leaves are simple (lobed or unlobed but not separated into leaflets)

  Stipule features

  NA

• Place

  Habitat

  terrestrial

  New England state

  Massachusetts

  Specific habitat

  man-made or disturbed habitats

• Stem, shoot, branch

  Branched tendrils

  NA

  Hair between stem nodes

  the stem has hairs between the nodes

  Hairs between stem nodes

  at least some of the hairs on the stem are branched

  Leaves on stem

  there is at least one full leaf above the base of the flowering stem

  Plant height

  Up to 100 cm

  Stem hair distribution

  the hairs on the stem are distributed more of less uniformly

  Stem orientation

  the stems are upright or angled outwards

  Tendril origin

  NA

  Tendrils

  the plant does not have tendrils

Wetland status

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae