Gossypium tomentosum

Gossypium tomentosum, commonly known as maʻo, huluhulu or Hawaiian cotton, is a species of cotton plant that is endemic to the Hawaiian Islands. Genetic studies indicate that Hawaiian cotton is related to American species of Gossypium, with its closest relative Gossypium hirsutum.^[2]

Gossypium tomentosum
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Malvales
Family:	Malvaceae
Genus:	Gossypium
Subgenus:	G. subg. Karpas
Species:	G. tomentosum
Binomial name
Gossypium tomentosum Nutt. ex Seem.[1]

Description

Maʻo is a shrub that reaches a height of 1.5–5 ft (0.46–1.52 m) and a diameter of 5–10 ft (1.5–3.0 m).^[3] The seed hairs (lint) are short and reddish brown, unsuitable for spinning or twisting into thread. Its flowers are bright yellow and have from 3-5 lobes that bloom in late summer to winter.^[4]

Distribution

Its ancestor may have come to the islands from the Americas as a seed on the wind or in the droppings of a bird, or as part of floating debris.^[5]

Habitat

It inhabits low shrublands at elevations from sea level to 120 m (390 ft).^[6] They can be found on all main Hawaiian islands besides Hawai'i, otherwise known as the Big Island.^[7]

Modern use

Gossypium tomentosum has been bred with other cotton plants to try and get a more persistent cotton plant for.^[8] Ma’o has also been studied with the interest in greater pollination consistency.^[9][10] Additionally, Ma’o has been used to breed with other cotton plants to try and build up more resilience to salt.^[11] The salinity of its habitat is high due to its close proximity to the ocean and thus has a resistance to salt more than other species.

Cultural significance

Native Hawaiians use maʻo flowers to make a yellow dye.^[12] They were also used to aid childbirth and mitigate stomach aches.^[13]

Conservation status

Gossypium tomentosum is under the G2 status and is considered at risk of extinction due to its lack of reach around the world.^[14] This conservation status comes from the NatureServe definitions on different elements that affect species diversity.^[15]