Introduced
`Ihi 'ai is also known as 'Ihi 'ai, 'Ihi 'awa, 'Ihi maka 'ula, 'Ihi makole, or the Hawaiian Waterclover.
The branches of wood sorrel are erect, creeping, about 11" long borne with small hairs while the roots are fibrous and branched. The leaves are small, slightly ovate and about .1" to .5" long and .3" to .7" broad. The flowers are inflorescence yellow growing in cluster of 1-6 and petals are 19 to 22 feet long. The fruit is a cylindrical capsule .3" to .7" long, containing seeds.
`Ilhi 'ihi prefers impoverished soils, growing in abandoned fields and along roadsides. It thrives best in well-drained and loamy acidic soil, preferring no shade.
http://www.spicesmedicinalherbs.com/oxalis-corniculata.html#cultivation