The Unique Plant: Mimosa Plant
Mimosa is a genus of about 400 species of herbs and shrubs, in the subfamily Mimosoideae of the legume family Fabaceae. There are two species in the genus that are notable. One is Mimosa pudica, because of the way it folds its leaves when touched or exposed to heat. It is native to southern Central and South America but is widely cultivated elsewhere for its curiosity value, both as a houseplant in temperate areas, and outdoors in the tropics. Outdoor cultivation has led to weedy invasion in some areas, notably Hawaii. The other is Mimosa tenuiflora, which is best known for its use in shamanic ayahuasca brews due to the psychedelic drug dimethyltryptamine found in its root bark.
Mimosa pudica
Mimosa pudica (from Latin: pudica "shy, bashful or shrinking"; also called sensitive plant, sleepy plant and the touch-me-not), is a creeping annual or perennial herb, the compound leaves fold inward and droop when touched or shaken, to protect them from predators, re- opening minutes later. The species is native to South America and Central America, but is now a pantropical weed. It grows mostly in shady areas, under trees or shrubs. The stem is erect in young plants, but becomes creeping or trailing with age. It can hang very low and become floppy. The stem is slender, branching, and sparsely to densely prickly, growing to a length of 1.5 m (5 ft). The leaves of the mimosa pudica are compound leaves. The leaves are bipinnately compound, with one or two pinnae pairs, and 10–26 leaflets per pinna. The petioles are also prickly. Stalked pale pink or purple flower heads arise from the leaf axils in mid summer with more and more flowers as the plant gets older. The globose to ovoid heads are 8–10 mm in diameter. On close examination, it is seen that the floret petals are red in their upper part and the filaments are pink to lavender. The fruit consists of clusters of 2–8 pods from 1–2 cm long each, these being prickly on the margins. The pods break into 2–5 segments and contain pale brown seeds some 2.5 mm long. The flowers are pollinated by the wind and insects. The seeds have hard seed coats which restrict germination.
Plant movement
Mimosa pudica is well known for its rapid plant movement. Like a number of other plant species, it undergoes changes in leaf orientation termed "sleep" or nyctinastic movement. The foliage closes during darkness and reopens in light. The leaves also close under various other stimuli, such as touching, warming, blowing, or shaking. These types of movements have been termed seismonastic movements. The movement occurs when specific regions of cells lose turgor pressure, which is the force that is applied onto the cell wall by water within the cell vacuoles and other cell contents. When the plant is disturbed, specific regions on the stems are stimulated to release chemicals including potassium ions which force water out of the cell vacuoles and the water diffuses out of the cells, producing a loss of cell pressure and cell collapse; this differential turgidity between different regions of cells results in the closing of the leaflets and the collapse of the leaf petiole. This characteristic is quite common within the Mimosoideae subfamily of the legume family, Fabaceae. The stimulus can also be transmitted to neighboring leaves. It is not known exactly why Mimosa pudica evolved this trait, but many scientists think that the plant uses its ability to shrink as a defense from herbivores. Animals may be afraid of a fast moving plant and would rather eat a less active one. Another possible explanation is that the sudden movement dislodges harmful insects.
Mimosa tenuiflora
Mimosa tenuiflora, syn. Mimosa hostilis is a perennial tree or shrub native to the northeastern region of Brazil and found as far north as southern Mexico. It is most often found in lower altitudes, but it can be found as high as 1000 m. The fern-like branches have leaves that are Mimosa like, finely pinnate, growing to 5 cm long. Each compound leaf contains 15–33 pairs of bright green leaflets 5–6 mm long. The tree itself grows up to 8 m tall and it can reach 4–5 m tall in less than 5 years. The white, fragrant flowers occur in loosely cylindrical spikes 4–8 cm long. In the Northern Hemisphere it blossoms and produces fruit from November to June or July. In the Southern Hemisphere it blooms primarily from September to January. The fruit is brittle and averages 2.5–5 cm long. Each pod contains 4–6 seeds that are oval, flat, light brown and 3–4 mm in diameter. There are about 145 seeds/g. In the Southern Hemisphere, the fruit ripens from February to April. The tree's bark is dark brown to gray. It splits lengthwise and the inside is reddish brown. The tree's wood is dark reddish brown with a yellow center. It is very dense, durable and strong, having a density of about 1.11 g/cm³. Mimosa tenuiflora does very well after a forest fire, or other major ecological disturbance. It is a prolific pioneer plant. It drops its leaves on the ground, continuously forming a thin layer of mulch and eventually humus. Along with its ability to fix nitrogen, the tree conditions the soil, making it ready for other plant species to come along.
Medicinal uses
The Mayans of Mexico have used roasted Mimosa tenuiflora "tepezcohuite" bark to treat lesions of the skin for over a thousand years. A tea made of the leaves and stem has been used to treat tooth pain. For cases of cough and bronchitis, a water extract (decoction) of Mimosa tenuiflora is drunk. A handful of bark in one liter of water is used by itself or in syrup. The solution is drunk until the symptoms subside. One preliminary clinical study found Mimosa tenuiflora to be effective in treating venous leg ulcerations.
Other uses
The tree is an acceptable source of forage or fodder for animals, providing vital protein and other nutrients. It does well in the dry season and in drought, while providing life saving food for local livestock and animals. Cows, goats and sheep eat the pods and leaves. There seems to be evidence that Mimosa tenuiflora forage or fodder causes development defects to pregnant ruminants in Brazil. The tree is an important source of forage for bees, especially during the dry season and in the beginning of the wet season. Like most plants in the Fabaceae family, Mimosa tenuiflora fertilizes the soil via nitrogen fixing bacteria. The tree is useful in fighting soil erosion and for reforestation. Mimosa tenuiflora is a very good source of fuel wood and works very well for making posts, most likely because of its high tannin content (16%), which protects it from rot. Due to its high tannin content, the bark of the tree is widely used as a natural dye and in leather production. It is used to make bridges, buildings, fences, furniture and wheels. It is an excellent source of charcoal.
Source: Google