Trees and Oak Savanna

Link to Google Map of all labeled trees

Click to read about the Thurston Nature Center Oak Savanna


Oak Savanna

The Thurston Nature Center Oak Savanna was established in 2009 with the planting of 20 oak trees after a successful 2008 proposal to the Michigan Department of Natural Resources Urban and Community Forestry Program.

This precious Oak Savanna habitat is 0.7 acres at the south side of the Thurston Nature Center and the northeast side of the Thurston Elementary School playground. Twenty oaks were planted in 2009, with Thurston Elementary students helping. Since then there have been two Eagle Scout projects, and help from Thurston students, to convert the unmowed, non-native turf grass to a diverse planting of native ground-level grasses and flowers. These activities occurred in 2015-2017. Subsequent work included mowing and burning to reduce weeds while the native plants took hold. By 2023, the Savanna was a fully functioning native-plant habitat, attracting butterflies, moths, bees, grasshoppers, many bird species and even garter snakes.

The Thurston Nature Center oak savanna includes five each of these four species of native Michigan oaks

  • Bur Oak
  • Chinkapin Oak
  • Swamp White Oak
  • White Oak

Background on Oak Savannas: Between 4000 and 6000 years ago, long before Europeans settled here,
oak savannas (also called oak openings) were quite common around what is now Ann Arbor. Native Americans regularly burned savannas (and other habitats) to improve conditions for game birds and mammals. When the earliest land surveyors first explored our area in the early 1800s, they noted seeing many of these oak savannas. Like prairies, oak savannas are a fire-dependent habitat type in an area with limited rainfall, but the rolling grassland of the savanna is scattered with isolated trees. The trees are primarily large, old oaks, and there is between 10 and 60% canopy, with or without a shrubby layer below. The predominantly grass-covered ground layer is composed of species associated with both prairie and forest communities. Sadly, oak savannas were virtually eliminated in Michigan long ago, as they were some of the easiest areas to convert to agriculture. The Thurston community is proud of having replanted and lovingly cared for this Oak Savanna.

Map of Oak Savanna 2024 – records their size in 2024, 15 years after the 20 trees were planted, showing that 14 of the 20 are now over 6″ in diameter. All 20 trees planted in 2009 have survived, helping the area grow into an excellent demonstration of the oak savanna plant community.

Here is a drone photo of oak savanna in July, 2024 showing a healthy habitat area for this rare habitat type:

July, 2024 aerial photo of the Thurston oak savanna, showing an ecologically health area of this rare habitat type.

Learn more about the Oak Savanna and its history in these founding documents:

Additional photos from the planting of the Oak Savanna in 2009:

Here is the same location as the photo above, but in 2024, showing all the growth in the intervening 15 years:

Some additional photos of the oak savanna trees, showing examples of verifying the size (circumference and diameter) in September of 2024:

Measuring an oak savanna tree in September, 2024.
Measuring oak savanna tree in September, 2024
Measuring an oak savanna tree in September 2024.
An oak savanna tree with  chinquapin oak label, in September 2024, 15 years after being planted