The ornamental design for a treetent, as shown and described.
FIG. 1 shows a top perspective view of a tree tent.
FIG. 2 shows a bottom perspective view thereof.
FIG. 3 shows a top plan view thereof.
FIG. 4 shows a bottom plan view thereof.
FIG. 5 shows an enlarged side elevation view thereof; the opposite side being a mirror image.
FIG. 6 shows an enlarged front side view thereof; and,
FIG. 7 shows an enlarged back side view thereof.
The broken lines shown are included for the purpose of illustrating the environment in which the article resides and form no part of the claimed design.