Fabaceae is a large and economically important family of flowering plants and for the lay person it is not always easy to sort out the orders, the subfamilies, the genera and the species in this family. The group is the third largest land plant family in terms of number of species, behind only the Orchidaceae and Asteraceae (http://en.wikipedia.org/wiki/Fabaceae).
The name Fabaceae comes from the Latin “faba” which means “bean”. Fabaceae is also called the pea family. Leguminosae is an older name still used and refers to the fruit of these plants which are called legumes.
There are three subfamilies:
In the Faboideae, the flowers have a specialized structure. “The upper petal, called the banner, is large and envelops the rest of the petals in bud, often reflexing when the flower blooms. The two adjacent petals, the wings, surround the two bottom petals. The two bottom petals are fused together at the apex (remaining free at the base), forming a boat-like structure called the keel.”(http://en.wikipedia.org/wiki/Fabaceae)
In the Mimosoideae, the flowers are globose inflorescences. All of the flowers in an inflorescence open at once.
The third group, the Caesalpinioideae mainly comprises of trees distributed in the moist tropics.
The subfamily Mimosoideae is subdivided into four tribes: Acacieae, Ingeae, Mimoseae, and Mimozygantheae.
After learning all this comes the task of discovering the binomial name. Does the acacia I know belong in one of these three subfamilies? Is it in the Acacieae tribe of the Mimosoideae subfamily? After checking out the internet images and the distribution information, Robinia pseudoacacia appeared to be the correct candidate. Is it named as pseudo acacia because it is not classified under the genus Acacieae but in the subfamily Faboideae? For the answers I would need to make the acquaintance of a botanist.
Robinia pseudoacacia is a deciduous tree of the genus Robinia in the subfamily Faboideae. It grows 4–25 meters tall. The leaves are pinnate and the flowers are white or pink, in pendulous racemes.
R. pseudoacacia is naturalized in Europe, Southern Africa and Asia. It grows so abundantly in Istanbul that it surprised me to learn that it is native to the southeastern United States and northern Mexico. The genus is named after the royal French gardeners Jean Robin and his son Vespasien Robin, who introduced the plant to Europe in the beginning of the 17th century.
Have I been able to make the description as complicated for you as it was for me?
Here is a stanza and my approximate translation from a classic song called Akasyalar Açarken-‘When the acacia are blooming’, that everybody still enjoys immensely. The very talented Yesari Asım Arsoy (1900-1992) must have found love to be uncomplicated when he wrote this song:
Yarim gelir yanıma, Kanı kaynar kanıma My love comes to my side, Gives me much love
Neşe katar canıma, Akasyalar açarken Adds joy to my soul, When the acacia are blooming