In the temperate uplands of the interior, as about Luang Prabang, Himalayan and Japanese species occur - oaks, pines, chestnuts, peach and great apple trees, raspberries, honeysuckle, vines, saxifrages, Cichoraceae, anemones and Violaceae; there are many valuable timber trees - teak, sappan, eagle-wood, wood-oil (Hopea), and other Dlpterocarpaceae, Cedrelaceae, Pterocarpaceae, Xylia, ironwood and other dye-woods and resinous trees, these last forming in many districts a large proportion of the more open forests, with an undergrowth of bamboo.
Examples are Umbelliferae as a family, saxifrages, holly, Acer, Rhamnus, Euonymus, Euphorbia, &c.
The green moss-like saxifrages are also a very distinct group, with dense tufted leaves which appear greener in winter than in summer.
Of Phanerogams, only the Dryas octopetala covers small areas of the debris, interspersed with isolated Cochlearia, &c., and, where a layer of thinner clay has been deposited in sheltered places, the surface is covered with saxifrages, &c.; and a carpet of mosses allows the arctic willow (Salix polaris) to develop. Where a thin sheet of humus, fertilized by lemmings, has accumulated, a few flowering plants appear, but even so their brilliant flowers spring direct from the soil, concealing the developed leaflets, while their horizontally spread roots grow out of proportion; only the Salix lanata rises to 7 or 8 in., sending out roots I in.