The savannas can be found in all of the regions in Thailand. Some are the result of major geological shifts like earthquakes or volcano eruptions occurring hundreds of thousands years ago, leaving infertile soil with very little vegetation. This type of forest is also the result of deforestation for agriculture. The mobile plantation results in the dried, infertile soil so the grasses grow over the land and dry season wildfires are common. The fires generally extend close to the tree line causing the grassland to expand every year. The savannas are characterized by grass and trees that are fire resistant. Yet, some useful herbs can be found even in these zones, such as Cotton wool grass, Thorn apple, Devil weed, Tio khon and bolete mushrooms. Each year, increasing in savannas means more deforestation, a serious threat that must be reversed immediately through forest and animal conservation.
Cotton wool grass
Imperata cylindrica (POACEAE )
Root: cool and moist taste; as diuretic, to treat excessive internal heat, fever, thirsty, inflammation of the urinary bladder.
Leaf: boil in water and use to take a bath to treat urticarial, itchy rash and to relieve muscular pain for post-labor.
Tio khon
Cratoxylum formosum subsp. pruniflorum (CLUSIACEAE)
Root: as diuretic for dysuria.
Thorn Apple
Datura metel var. metel (SOLANACEAE)
Ground fresh leaf: apply externally to relieve inflammation of abcesses and sprains.
Flower: air-dry, mix with tobacco, smoke for antiasthma.
Seed: boil in vegetable oil and applied to treat ringworm and itchy rashes.
Leaf and twig: as antispasmodic, bronchodilator for asthmatic patients, and depress vomiting center in the brain, useful to control motion sickness.
Caution: causes dry mouth and throat.
Dusita
Utricularia delphinioides (LENTIBULARIACEAE )
Whole plant: as blood tonic
Devil weed
Chromolaena odorata (COMPOSITAE )
Leaf: grind with little lime water or salts, put on the wound to stop bleeding; contains 4,5,6,7-tetramethoxyflavone and calcium, which decrease blood clotting time. The leaf extract inhibit the growth of pus induced bacteria,Staphyllococcus aureus and Bacillus subtilis.