Horticulture Study

Saint Louis Zoo researchers are counting and identifying a wide variety of native and exotic plant species, including species of conservation concern, at the Saint Louis Zoo WildCare Park. The diversity of plants growing at this site is important to native animals that need these botanical habitats for survival.

Important First Step

Identifying what species are present on the property is an important first step in making informed decisions about future property uses, including collection planning and management, native wildlife corridor management, habitat management and restoration, and educational program development in terms of property design and use.


Over 100 species of plants have been identified so far in 2020. Some of the highlights include:

  • Pumpkin ash tree (critically endangered species)
  • Beakgrain
  • Bird's foot violet
  • Black cherry
  • Blackgum
  • Black oak
  • Black walnut
  • Blue vervain
  • Boxelder
  • Broadleaf arrowhead
  • Buckbrush
  • Butterweed
  • Chinkapin oak
  • Common milkweed
  • Cornsalad
  • Cottonwood
  • Ferns
  • Frostweed
  • Gray dogwood
  • Greenbriar
  • Groundnut
  • Hackberry
  • Hickory
  • Jewel weed
  • Lizard tail
  • Marsh milkweed
  • Monkey flower
  • Northern red oak
  • Overcup oak
  • Pawpaw
  • Persimmon
  • Sassafras
  • Sedges
  • Silver maple
  • Slippery Elm
  • Solomon's seal
  • Spicebush
  • Sugarberry
  • Sugar maple
  • Swamp white oak
  • Tick trefoil
  • White oak

  • Autumn olive (invasive)
  • Barberry (invasive)
  • Bush honeysuckle (invasive)
  • Chinese elm (invasive)
  • Japanese hops (invasive)

Scientific Methods

Observers walk transects, or sample areas, throughout the property's varying landscapes to identify plant species. Plants are identified by foliage, flowers, bark, buds, habit, location, and other visually identifiable characteristics.

Only non-invasive monitoring methods were used during this survey to determine species identification and population estimates.


Missouri is home to countless flowering and non-flowering plant species, including 735 species of conservation concern at the federal and state level. The variety of natural plant communities offers potential for great diversity among plant species at the WildCare Park. The federally threatened Boltonia decurrens (a species of aster) has been located on nearby property and the WildCare Park may serve as a site for further conservation of this listed species.

Zoo Conservation Programs

How You Can Help