Lewis & Short

calvesco, ĕre,

  1. I. v. inch. n. [calveo], to become bald (post-Aug.), Col. 6, 14, 7; Veg. 3, 4, 27; Plin. 10, 29, 41, § 78.
  2. II. Transf. to plants, to grow up thin or far apart, Col. 4, 33, 3.