from wiki, i really dont know what their
function is, just
what they are
"In
botany,
stipule (
Latin stipula: straw, stalk
[1]) is a term coined by
Linnaeus[1] which refers to outgrowths borne on either side of the base of a leafstalk (the
petiole). A pair of stipules is considered part of the anatomy of the
leaf of a typical
flowering plant, although in many species the stipules are inconspicuous or entirely absent (and the leaf is then termed
exstipulate).
Stipules are morphologically variable and might appear as
glands, scales,
hairs,
spines, or laminar (leaf-like) structures. A relationship exists between the anatomy of the stem node and the presence or absence of stipules. Most plants with
trilacunar nodes have stipules; species with
unilacunar nodes lack stipules "