The saxaul, black saxaul, sometimes sacsaoul or saksaul (Russian: saksaul, which is from Kazakh: seksevil, scientific name Haloxylon ammodendron), is a plant belonging to the Amaranthaceae.
The saxaul ranges in size from a large shrub to a small tree, 2-8 (rarely 12) m tall. It has a brown trunk 4-10 (up to 25) cm in diameter. The wood is heavy and coarse and the bark is spongy and water-soaked. The branches of the current year are green, older branches are brown, or grey to white. The leaves are reduced to very small cusp-like scales, so that the plant appears nearly leafless.
The inflorescences consist of short lateral shoots borne on stems of the previous year. The flowers are bisexual or male, very small, as long as or shorter than the bracteoles. The flowering period is from March to April.
In fruit, the perianth segments develop spreading pale brown or white wings. The diameter of the winged fruit is about 8 mm. The seed is 1,5 mm in diameter. The fruiting period is October to November.