Xanthium strumarium var. canadense (Beach clotbur)

Xanthium strumarium L. var. canadense (Mill.) Torr. & A. Gray

Xanthium acerosum Greene

Xanthium californicum Greene

Xanthium campestre Greene

Xanthium canadense Mill.

Xanthium cavanillesii Schouw

Xanthium californicum Greene var. rotundifolium Widder

Xanthium cenchroides Millsp. & Sherff

Xanthium commune Britton

Xanthium echinatum Murray

Xanthium glanduliferum Greene

Xanthium italicum Moretti

Xanthium macounii Britton

Xanthium oligacanthum Piper

Xanthium oviforme Wallr.

Xanthium pensylvanicum Wallr.

Xanthium saccharatum Wallr.

Xanthium speciosum Kearney

Xanthium strumarium L. ssp. italicum (Moretti) D. Löve

Xanthium strumarium L. var. oviforme (Wallr.) M. Peck

Xanthium strumarium L. var. pensylvanicum (Wallr.) M. Peck

Xanthium varians Greene

Beach clotbur, Canada cocklebur, rough cocklebur

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Magnoliopsida	Dicotyledons—plants with two initial seed leaves
Subclass	Asteridae	A large class that encompasses asters
Order	Asterales	Flowering plants with a central disk flower and surrounding petals, like daisies
Family	Asteraceae	The aster family, which also includes daisies and sunflowers; from the Greek ἀστήρ, “star,” for the star-shaped flowers
Genus	Xanthium	Cocklebur family, from Greek xanthos, “yellow”, possibly because a yellow dye can be prepared from this
Species	strumarium	From Latin strumosus, “swollen,” for the cockleburs
var.	canadense	“From Canada”

About plant names...

These plants are North American natives.

Identification: Cockleburs are 8-48" (20-121 cm) tall, and generally found near wet areas. Leaves are 2-6" (5-15 cm) long, on stalks about the same length, shaped like a cross between a heart and a maple leaf, with scalloped edges. Flowers are greenish, with male and female flowers on same plant. The oval-shaped burs that form from female flowerheads are the most distinctive identifying feature. They are ½-1½" (1.3-3.8 cm) long.

From Britton, Nathaniel Lord, and Brown, Addison, An illustrated flora of the northern United States, Canada and the British Possessions, 1913.

Online References:

Xanthium strumarium var. canadense on Forest and Kim Starr’s Starr Environmental site

Xanthium strumarium var. canadense on Wikimedia Commons

Xanthium strumarium var. canadense at the Lady Bird Johnson Wildflower Center

Xanthium strumarium var. canadense on SEINet—the Southwest Environmental Information Network

Xanthium strumarium var. canadense on luirig.altervista.org

Xanthium strumarium var. canadense description by Thomas H. Kent, last updated 25 May 2020.

10/4/2008 · Parker River National Wildlife Refuge, Plum Island, Massachusetts
≈ 4½ × 7" (11 × 17 cm)

9/23/2010 · Nova Scotia, Canada · By Kathy Williamson

10/4/2008 · Parker River National Wildlife Refuge, Plum Island, Massachusetts
≈ 9 × 6" (23 × 15 cm)

Range: Zones 3a-11:

About this map...