Lewis & Short

ablăquĕātĭo, ōnis, f. [ablaqueo],

  1. I. a digging or loosening of the soil round the roots of a tree, Col. 4, 4, 2; 4, 8, 2; Plin. 12, 15, 33, § 66 al.
  2. II. Concr., the trench itself made by digging, Col. 5, 10, 17 Schneid.