Leaves

A massive food factory that is one of a kind,
Taking in all CO2 leaving Oxygen behind!
Chlorophyll is a pigment that makes it look green,
When it varies in level, colours can be seen!
Caterpillar, locusts and insects do feed,
To a varying degree based on their need.
Modifications at times, they are definitely made,
As a thorn or tendril - whatever it takes!
Reticulate and parallel venations get seen,
Depending on the plant type, if you knew what I mean!