lamina— The blade or expanded part of a petal or leaf.
lance-elliptic— Descriptive of a leaf shape that falls between lance-shaped and elliptic.
lanceolate— Lance-shaped; several times longer than wide, broadest toward the base and tapering to the apex.
languid— A leisurely or relaxed pace.
lapilli— Pyroclastic rock (volcanic ejecta) in the general size range of 2 to 64 mm.
lapse rate— The decrease of air temperature with height.
larva(e)— A juvenile insect; usually does not look like the adult.
legume— The fruit of a pealike flower; members of the Family or Superfamily Leguminosae.
leks— Tightly clumped assemblies of courting males to which females are attracted for mating.
lepidopteran— A member of the Order Lepidoptera, comprising the butterflies and moths, which possess wings covered with scales.
ligule— Strap-shaped or tongue-shaped; the straight-sided part of a flower ("petal") in the Chicory Tribe of the Aster (Sunflower) Family.
limestone— Rock composed chiefly of calcium carbonate; soils derived from those rocks.
lithospheric plate— A layer of the Earth that includes the crust and part of the upper mantle, approximately 100 km thick.
loam— An easily crumbled mixture of clay, silt, and sand; said of soil; usually favorable for plant growth.