  We address the existence and origin of the lithium (Li) desert, a region in
the Li - T_eff plane sparsely populated by stars. Here we analyze some of the
explanations that have been suggested for this region, including mixing in the
late main sequence, a Li dip origin for stars with low Li abundances in the
region, and a possible relation with the presence of planets. To study the Li
desert, we measured the atmospheric parameters and Li abundance of 227 late-F
dwarfs and subgiants, chosen to be in the T_eff range of the desert and without
previous Li abundance measurements. Subsequently, we complemented those with
literature data to obtain a homogeneous catalog of 2318 stars, for which we
compute masses and ages. We characterize stars surrounding the region of the Li
desert. We conclude that stars with low Li abundances below the desert are more
massive and more evolved than stars above the desert. Given the unexpected
presence of low Li abundance stars in this effective temperature range, we
concentrate on finding their origin. We conclude that these stars with low Li
abundance do not evolve from stars above the desert: at a given mass, stars
with low Li (i.e., below the desert) are more metal-poor. Instead, we suggest
that stars below the Li desert are consistent with having evolved from the Li
dip, discarding the need to invoke additional mixing to explain this feature.
Thus, stars below the Li desert are not peculiar and are only distinguished
from other subgiants evolved from the Li dip in that their combination of
atmospheric parameters locates them in a range of effective temperatures where
otherwise only high Li abundance stars would be found (i.e., stars above the
desert).
