The Collaborative International Dictionary of English v.0.48:

Sparse \Sparse\, a. [Compar. Sparser; superl. Sparsest.] [L.
   sparsus, p. p. of spargere to strew, scatter. Cf. Asperse,
   Disperse.]
   1. Thinly scattered; set or planted here and there; not being
      dense or close together; as, a sparse population.
      --Carlyle.
      [1913 Webster]

   2. (Bot.) Placed irregularly and distantly; scattered; --
      applied to branches, leaves, peduncles, and the like.
      [1913 Webster]