I believe the plants you are referring to are the sorrels- of the genus
mame "Oxalis". The oxalis comes from oxalic acid which gives the leaves
of this plant a sour taste. When I was a boy I remember my mother
putting sorrel in her soups to give them a little tang.
Here in the woodland areas of Chicago, Illinois (USA) the most prominent
sorrel is the is the wood sorrel (Oxalis stricta). It is a short little
plant with small 5-petal yellow flowers. As you said, its leaves are
distinctly clover-like which droop and fold together at night.
JANVIER TRACY wrote:
>> Does anyone know of the plant name, in which it is open a majority of
> the day and closes at night. It looks like a clover, I think it is part
> of that family