Gossypium tomentosum, commonly known as Mao or Hawaiian cotton, is a species of cotton plant

Gossypium

Gossypium is the cotton genus. It belongs to the tribe Gossypieae, in the mallow family, Malvaceae, native to the tropical and subtropical regions from both the Old and New World. The genus Gossypium comprises around 50 species , making it the largest in species number in the tribe Gosssypioieae....

 that is endemic to the Hawaiian Islands

Hawaiian Islands

The Hawaiian Islands are an archipelago of eight major islands, several atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll...

. It inhabits low shrublands

Hawaiian tropical low shrublands

The Hawaiian tropical low shrublands are a tropical savanna ecoregion in the Hawaiian Islands. These shrublands cover an area of in the leeward lowlands of the main islands and most of the smaller islands, including the Northwestern Hawaiian Islands. The ecoregion includes both grasslands and...

 at elevations from sea level to 120 m (393.7 ft). Mao is a shrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

 that reaches a height of 1.5–5 ft (0.4572–1.5 m) and a diameter of 5–10 ft (1.5–3 m). The seed hairs (lint) are short and reddish brown, unsuitable for spinning or twisting into thread.

Genetic studies indicate that Hawaiian cotton is related to American species of Gossypium, with its closest relative Gossypium hirsutum

Gossypium hirsutum

Gossypium hirsutum, known as Upland Cotton or Mexican Cotton, is the most widely planted species of cotton in the United States, constituting some 95% of all cotton production and is native to Central America and possibly Mexico Worldwide, the figure is about 90% of all production for this...

. Its ancestor may have come to the islands from the Americas

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

as a seed on the wind or in the droppings of a bird, or as part of floating debris.

External links

• Gossypium tomentosum (ma'o) information from the Hawaiian Ecosystems at Risk project (HEAR)
• Gossypium tomentosum (ma'o) images from Forest & Kim Starr