The Arboretum has undergone two expansions. In 1992, the southeast area near the old Haynes Gym was added. The drainage basin between the Student Union Building and Rotary Hall, and the lower pond were constructed in 1996. Adding vegetation to the drainage basins has slowed runoff and limited erosion of the clay hills.
The existing canopy consists of the surviving trees from the time of Centenary's move to Shreveport in 1909; many of these are past maturity and in decline, and some have since died. The larger trees are at least 125 years old. These include white oak, southern red oak, loblolly pine, and post oak. The Arboretum area has lost several post oaks to oak wilt. The Arboretum plantings are intended to eventually replace these trees, while displaying the tremendous diversity of Louisiana and southeastern native species. Emphasis has been placed on trees and shrubs first. In the past five years, now that growth potential for larger specimens is clear, there has been an attempt to add a significant herbaceous under-story plant component. The Arboretum collection is intended to serve both an aesthetic purpose and an educational purpose for Centenary students and the Shreveport community alike.