Gypsum

Gypsum [ Geology - Ecology ]
Adjective: Gypseous - Gypsiferous

Dictionary of botanic terminology - index of names


	*The gypsum is a natural crystalline colourless to white mineral consisting of hydrated calcium sulphate, with the chemical formula of CaSO₄ - 2H₂O*

Gypsum is a common rock that occurs naturally in sedimentary rocks formed under heat and pressure from sediments in ocean salt water or by evaporation. It is the most common natural sulphate mineral and forms beds and lenses interstratified with limestone, shale, and clay. Gypsum also occurs in volcanic fumarolic deposits and as an accessory mineral in metalliferous veins; the mineral often appears as outward-curving flowers which have the shape of a petal. The rock is softer than limestone.
It is a dry natural fertilizer or amendment that supplies two important micronutrients: calcium and sulphur, it is used to ameliorate soils with a high exchangeable sodium fraction.
Also used in potting-mix for ornamental plants that need substrates rich in calcium.

Gypseous = Of, relating to, or containing gypsum
Gypsiferous = Containing gypsum

The particular plants adapted to live in such a gypsiferous habitat are called Gypsophiles or Gypsophilous plant.
A number of cactus and succulents are gypsophiles and need some gypsum grit/sand in the potting mix.

Gypsiferous soil [ Geology - Ecology ]
(also: Gypseous soil)


	*A soil rich in gypsum, containing at least a percent of gypsum.*

The range varies widely from 1% to 5% in the different country.

Advertising

Holdfast roots [ Botany ]
Dictionary of botanic terminology - index of names

Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.

Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans), develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994