Sensitive

Description:

A creeper with a thorny stem about 1 to 1,5 m in length; producing compound leaves and very attractive pink flower heads. Thanks to its symbiotic relationship with nitrogen-fixing bacteria , the plant is capable of transforming the atmospheric nitrogen and storing it in root nodules, where the bacteria establish itself.

Habitat:

Native to American continents, now it is spread almost everywhere... I observed it in rural areas of every African country I travelled to, and in Asia too - but I never saw it in Europe. Here, as a weed on agricultural lands, road shoulders, and beach edges.

Notes:

The plant has two very interesting characteristics - first is the well known and well-described the phenomenon of movement. It is capable to close its leaves when touched (thought to be a defense mechanism), or when needing water (reducing the evapotranspiration). The second is the capacity, like all Fabaceae members, to fix the nitrogen from air. In that respect, and thanks to its resilience to drier conditions it was an interesting plant for agriculture in nitrogen poor dry soils. Today, in most cases is considered an invasive weed.