OregonFlora: Peltandra virginica vs. Araceae

	Peltandra virginica	Araceae
	green arrow arum	arum family
Habit	Herbs to 150 cm.	Herbs aquatic or terrestrial; annual or perennial; generally monoecious.
Leaves	up to 50 cm long, 5–20 cm wide, with lateral veins of 2 different thicknesses.	basal; simple to pinnately or palmately compound, with a membranous basal sheath, or lacking true leaves and plant body highly reduced.
Inflorescences	spathes uniformly green or green with white or yellow-green margins; spadices 50% to almost as long as spathes.	indeterminate spikes with many unisexual or bisexual flowers clustered on a fleshy axis (spadix) that is subtended by a large; leaf-like or petaloid bract (spathe), or reduced to a single bisexual flower (interpreted by some to be 2 unisexual flowers) in a pouch or cavity.
Flowers		unisexual or bisexual; tepals usually absent, sometimes 4–6; fleshy and inconspicuous; stamens 1–6 and free or 2–12 and connate to form a synandrium; pistil 1; ovary 1; superior to half inferior and embedded in the spadix, 1(4)-locular; style 1.
Fruits	green to purple-green berries.	berries or follicles.
2n	=28.

	Peltandra virginica	Araceae
Distribution	[WildflowerSearch map] [BONAP county map]	[BONAP county map]
Discussion	Freshwater and low salinity wetlands. Flowering Apr–Sep. 0–50 m. CR. CA, WA; eastern North America. Exotic. This species is native to eastern North America and was likely introduced to Oregon as an ornamental.	Cosmopolitan, mostly tropical. Approximately 115 genera; 8 genera treated in Flora. Two different types of inflorescences are characteristic of this family. The typical aroid inflorescence is a spadix, a fleshy spike with many flowers, subtended by a spathe, a large, leaf- or petal-like bract. Plants in subfamily Lemnoideae (formerly family Lemnaceae) have inflorescences consisting of one or two stamens and a single pistil, which has been interpreted as either a single, highly reduced flower or a small inflorescence with two or three unisexual flowers. The minute, green, herbaceous plant bodies of the Lemnoideae lack true leaves and stems and have been referred to by various terms including thalli, thalloid stem/leaf units, and fronds. The phrase ‘plant body’ is used in this treatment. Reduction of both reproductive and vegetative parts leaves few characteristics to distinguish taxa within Lemnoideae. Reproduction by budding is common. Plants have one or two budding pouches or a basal cavity from which daughter plants arise. Turions (sometimes called winter buds) are smaller than the mother plant, usually darker in color, and filled with starch grains. They are produced in budding pouches in the fall, eventually detach, and then sink to the bottom of the water body. In the spring, they float to the surface and resume growth. Grown for showy inflorescences and glossy leaves, several exotic aroid species are cultivated in Oregon. Arum italicum, Peltandra virginica, and Zantedeschia aethiopica are occasionally escaped ornamentals treated fully in this volume. Dracunculus vulgaris (dragon arum or voodoo lily) was observed in a city park in St. Helens, Columbia County, and collected in a city park in Roseburg, Douglas County. It is probably persisting from cultivation and is not known to spread. Dracunculus vulgaris has a dark purple spadix and spathe with a fetid, rotting flesh odor, and large, palmately divided leaves. Pistia stratiotes (water lettuce) has been collected twice, once in the Willamette River in Portland (2013), and again in Fern Ridge Reservoir (2014). It is highly doubtful, however, that these plants have persisted. It is a free-floating aquatic plant with light green, spatulate to obovate leaves in a dense rosette 15–30(40) cm in diameter.
Source	Flora of Oregon, volume 1, page 150 Katie Mitchell	Flora of Oregon, volume 1, page 146
Web links	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: CA, OR Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Araceae

green arrow arum

arum family

Habit

Herbs to 150 cm.

Herbs aquatic or terrestrial; annual or perennial; generally monoecious.

Leaves

up to 50 cm long, 5–20 cm wide, with lateral veins of 2 different thicknesses.

basal; simple to pinnately or palmately compound, with a membranous basal sheath, or lacking true leaves and plant body highly reduced.

Inflorescences

spathes uniformly green or green with white or yellow-green margins;

spadices 50% to almost as long as spathes.

indeterminate spikes with many unisexual or bisexual flowers clustered on a fleshy axis (spadix) that is subtended by a large; leaf-like or petaloid bract (spathe), or reduced to a single bisexual flower (interpreted by some to be 2 unisexual flowers) in a pouch or cavity.

Flowers

unisexual or bisexual;

tepals usually absent, sometimes 4–6; fleshy and inconspicuous;

stamens 1–6 and free or 2–12 and connate to form a synandrium;

pistil 1;

ovary 1; superior to half inferior and embedded in the spadix, 1(4)-locular;

style 1.

Fruits

green to purple-green berries.

berries or follicles.

=28.

Peltandra virginica

Araceae

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Freshwater and low salinity wetlands. Flowering Apr–Sep. 0–50 m. CR. CA, WA; eastern North America. Exotic.

This species is native to eastern North America and was likely introduced to Oregon as an ornamental.

Cosmopolitan, mostly tropical. Approximately 115 genera; 8 genera treated in Flora.

Two different types of inflorescences are characteristic of this family. The typical aroid inflorescence is a spadix, a fleshy spike with many flowers, subtended by a spathe, a large, leaf- or petal-like bract. Plants in subfamily Lemnoideae (formerly family Lemnaceae) have inflorescences consisting of one or two stamens and a single pistil, which has been interpreted as either a single, highly reduced flower or a small inflorescence with two or three unisexual flowers. The minute, green, herbaceous plant bodies of the Lemnoideae lack true leaves and stems and have been referred to by various terms including thalli, thalloid stem/leaf units, and fronds. The phrase ‘plant body’ is used in this treatment. Reduction of both reproductive and vegetative parts leaves few characteristics to distinguish taxa within Lemnoideae. Reproduction by budding is common. Plants have one or two budding pouches or a basal cavity from which daughter plants arise. Turions (sometimes called winter buds) are smaller than the mother plant, usually darker in color, and filled with starch grains. They are produced in budding pouches in the fall, eventually detach, and then sink to the bottom of the water body. In the spring, they float to the surface and resume growth. Grown for showy inflorescences and glossy leaves, several exotic aroid species are cultivated in Oregon. Arum italicum, Peltandra virginica, and Zantedeschia aethiopica are occasionally escaped ornamentals treated fully in this volume. Dracunculus vulgaris (dragon arum or voodoo lily) was observed in a city park in St. Helens, Columbia County, and collected in a city park in Roseburg, Douglas County. It is probably persisting from cultivation and is not known to spread. Dracunculus vulgaris has a dark purple spadix and spathe with a fetid, rotting flesh odor, and large, palmately divided leaves. Pistia stratiotes (water lettuce) has been collected twice, once in the Willamette River in Portland (2013), and again in Fern Ridge Reservoir (2014). It is highly doubtful, however, that these plants have persisted. It is a free-floating aquatic plant with light green, spatulate to obovate leaves in a dense rosette 15–30(40) cm in diameter.

Source

Flora of Oregon, volume 1, page 150
Katie Mitchell

Flora of Oregon, volume 1, page 146

Web links