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- Xyridaceae
- Xyris
- Xyris difformis
Xyris difformis — bog yellow-eyed-grass
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Facts
Bog yellow-eyed-grass is native to southern and eastern North America, and is common in much of New England. It grows in lake and pond shores, and in bogs and fens, on sandy or peaty soils.
Habitat
Bogs, fens, shores of rivers or lakes
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
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade shape
- the leaf blade is linear (very narrow with more or less parallel sides)
- Leaf blade length
- 50–500 mm
- Flower petal color
-
- white
- yellow
- Flower petal length
- 4 mm
- Petal fusion
- the perianth parts are separate
- Inflorescence type
- the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- 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)
-
Clonal plantlets
- Axillary bulblets
- there are no bulblets being produced in axils
-
Flowers
- Anther attachment
- the anther is attached by its base to the filament
- Bulblets replace flowers
- there are no bulblets where the flowers are located
- Carpels fused
- the carpels are fused (the number of carpels equals the number of locules)
- Flower petal color
-
- white
- yellow
- Flower petal length
- 4 mm
- Flower symmetry
-
- there are two or more ways to evenly divide the flower (the flower is radially symmetrical)
- there is only one way to evenly divide the flower (the flower is bilaterally symmetrical)
- Form of style
- the style is branched above the base
- Fringed petal edges
- the petals are not fringed
- Hairs on flower stalk
- NA
- Inflorescence length
- 5–15 mm
- Inflorescence type
- the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)
- Marks on petals
- there are no noticeable marks on the petals
- Nectar spur
- the flower has no nectar spurs
- Number of pistils
- 1
- Number of styles
- 1
- Ovary position
- the ovary is above the point of petal and/or sepal attachment
- 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 length
- 5–7 mm
- Sepals fused only to sepals
- the sepals are separate from one another
- Spathe
- the plant does not have a spathe
- Spathe form
- NA
- Stamen number
- 3
- Stamen position relative to petals
- the stamens are lined up with the sepals
- Stamens fused outwards
- the stamens are fused to the petals or tepals at or near their bases
- Style petal-like
- the style is not broad and flattened like a petal
- Tepals
- the petals and sepals are different in size and color
-
Fruits or seeds
- Berry color
- NA
- Capsule ridges
- there are no ribs or wings on the capsule
- Fruit compartments
- there is only one locule in 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)
- Other markings on berry
- NA
-
Glands or sap
- Sap
- the sap is clear and watery
-
Growth form
- Lifespan
- the plant lives more than two years
- Underground organs
-
- the plant has a rhizome (a horizontal underground stem with roots growing from it)
- the plant has one or more swollen storage organs underground, such as bulbs, tubers or corms
-
Leaves
- Leaf arrangement
- alternate: there is one leaf per node along the stem
- Leaf blade basal lobes
- the leaf blades do not have basal lobes
- Leaf blade base
- 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
- Leaf blade cross-section
- the leaf blade is more or less flat in cross-section
- Leaf blade faces
- the surfaces of the leaf blade are composed of tissues from the abaxial side only
- Leaf blade form
- Fully-formed (i.e., expanded), +/- green leaf blades are found somewhere on the plant
- Leaf blade length
- 50–500 mm
- Leaf blade shape
- the leaf blade is linear (very narrow with more or less parallel sides)
- Leaf blade surface colors
- the upper side of the leaf blade is relatively uniform in color
- Leaf blade veins
- the lateral veins are parallel or slightly arched in the direction of the tip
- Leaf blade width
- Up to 7 mm
- Leaf type
- the leaves are simple (i.e., lobed or unlobed but not separated into leaflets
- Stipule twining
- NA
- Stipules
- there are no stipules on this plant
-
Place
- Habitat
- wetlands
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- bogs
- fens
- shores of rivers or lakes
-
Scent
- Plant odor
- the leaves have no particular smell
-
Stem, shoot, branch
- Flowering stem growth form
- the flowering stem is held upright
- Flowering stem leaves
- there are no true leaves on the flowering stem
Wetland status
Occurs only in wetlands. (Wetland indicator code: OBL)
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)
- Vermont
- historical (S-rank: SH)
var. difformis
- Massachusetts
- widespread (S-rank: S5)
Subspecies and varieties
Our variety is Xyris difformis Chapman var. difformis.
From Flora Novae Angliae dichotomous key
1. Xyris difformis Chapman var. difformis N
bog yellow-eyed-grass. CT, MA, ME, NH, RI, VT. Sandy and peaty lake and pond shores, bogs, acidic fens.
Native to North America?
Yes
Sometimes confused with
- Xyris montana:
- sheaths minutely papillose, leaves mostly 0.8–2 mm wide, floral scales mostly 3–4 mm long, erose or minutely fimbriate along the margins, lacking a well-defined, green central region (vs. X. difformis, with sheaths smooth, leaves than 2–7 mm wide, floral scales mostly 5–7 mm long, entire, with a well-defined, green central area).
- Xyris smalliana:
- tips of lateral sepals exserted beyond floral scales, seeds 0.6-0.8 mm long, and spikes mostly 10–20 mm tall, the apex usually rounded (vs. X. difformis, with the tips of lateral sepals concealed by floral scales, seeds 0.5 mm long, and spikes 5–15 mm tall, the apex usually acute).