Variations in the morphological characteristics of Stipa tenacissima fiber: The case of Tunisia

Esparto fibers are cellulose-based fibers extracted from esparto (Stipa tenacissima) leaves. Morphological characteristics (length, width, and coarseness) of esparto fibers are analyzed in relation to growing conditions and plant biology. Seven localized sites in Kasserine in central western Tunisia are examined. The analysis of variance showed that all investigated characteristics vary significantly with site, season, and leaf level. Leaves reach minimum level in winter and maximum level in fall. Fiber differentiation is closely related to the vegetative cycle. Fibers are short and wide at the leaf base (basal level) and grow longer and thinner above the leaf. Results on the raw material (esparto leaves) were confirmed by results on esparto pulp.

► Esparto grass is used as a main source of fiber for paper making.
► The fibers of the esparto leaf begin elongating in the basal part of the leaf in winter and finish in fall when the leaves mature.
► Fiber differentiation is closely related to the vegetative cycle.
► The results of this study could be used to develop a suitable harvesting program for this natural resource that respects its biology.