Passport Oak Cliff

Established in 2005 on land once occupied with apartments, the five-acre Twelve Hills Nature Center is being restored to Blackland Prairie –the predominant ecoregion of North Texas for thousands of years. Less than 0.5% of the Blackland Prairie ecosystem remains intact, making restoration projects like ours all the more crucial to maintaining native biodiversity and North Texas’s ecological and cultural heritage.

Watch your step, as you move throughout the nature preserve you’ll find remnants of the old apartment complex. Bricks in the walkway, old telephone pole stumps, and bits of rebar can be seen poking out of the ground.

Please enjoy your walk around our little slice of blackland prairie.

Front Meadow

Look into the meadow and notice grasses from 3 feet to six feet tall. The long leaves are a blue-ish green. The dominant one is Indian grass, Sorghastrum nutans. Watch for it as you proceed on your walk. Some will have a plume with tiny yellow flowers.

The Blackland Prairie is composed to diverse plant communities. North Central Texas hosted a tallgrass prairie composed of the big four prairie grasses: Big Bluestem, Little Bluestem, Switchgrass and Indiangrass) and many other native grasses. Wildflowers grew throughout. Over three hundred different plants grew and provided sustenance for hundreds of different insects that support, birds, small animals, reptiles etc., which support bigger animals and so on. Twelve Hills has over 250 plant species today and is being restored to a Blackland Prairie.

Prairie grasslands serve as CO2 sinks and provide oxygen to the atmosphere. They remove CO2 from the air in the same way trees do. They provide habitat for prairie–specific plants and wildlife.

Top of the Hill

Look for a 12-18 inch tall plant with purple flowers. It is Liatris mucronata, also known as gayfeather or blazing star. It grows from a bulb and is very drought resistant.

Blooms in October and provides nectar to butterflies, bees, and other insects during fall, when fewer flowers are blooming.

This area is being restored to a short grass prairie. The soil here is shallow and limestone or chalk rock is not far beneath the surface. Some Blackland Prairie plants are adapted to grow in shallow areas of limestone-based soil. They are rare and not available from plant nurseries.


Back Meadow

Do you recognize the tall yellow flower? It is goldenrod! Solidagao specoes, which is in the aster family. It’s one of the most widespread plants that bloom in the fall and provides nectar when most other plants are not flowering. Monarch butterflies passing through as well as bees, wasps, flies and many other pollinators benefit. It’s easy to grow and drought resistant.

Look across the meadow to see many light blue-ish green tall grasses. They are some of the grasses that form a tallgrass prairie.

Creek Watershed

The creek, which runs through a ravine beyond the fence, drains water into Coombs Creek, and flows into the Trinity River, and on to the Gulf of Mexico. You are in the Trinity River Watershed.

By keeping the TRW clean, you protect aquatic plants and insects, fish and amphibians, birds, and land-based plants and wildlife. Some easy but important ways to keep our watershed clean include: picking up litter, picking-up after your dog and disposing of oil, grease, cleaning compounds, etc. properly. Join Oak Cliff Ploggers to find clean-up events in Oak Cliff.

Founder's Tree

Walk under the big live oak tree! It’s known as the Founder’s Tree because its long winding branches give the appearance of Mother Nature enveloping us in her arms. It’s a symbol of bringing this disturbed land back to a lush Blackland Prairie and nurturing visitors with the benefits nature.

There are many types of oak trees at Twelve Hills and in Oak Cliff, also. Did you know that they provide essential food for baby birds?

400+ species of moths reproduce on oak trees. Their caterpillars are packed with protein and carotenoids and are fairly big and easy to digest. They provide highly nutritious food for baby birds. Carolina chickadees have been observed bringing 350 to 570 caterpillars a day to their nestlings depending on the number of nestlings. Oaks are tremendously important for providing habitat for moths, and thus food for birds, cherries, willow, and other trees are less so. Oaks are essential to a bird’s successful reproduction! Without them, our bird populations would decline.

— Nature’s Best Hope, Douglas Tallemy, pages 130-146

Top of the Hill Timbergrove Side

Notice all the airy looking plants with tiny aster-like yellow flowers. This is broomweed. The plant was used as a broom by American Indians and early settlers, thus its name.

American Indians used many of the native plants of the Blackland Prairie for food and medicinal purposes. The Comanche tribe made a poultice of boiled broomweed flowers into a jelly and treated eczema and skin rashes with it used it.

Broomweed provides cover and food (seeds) for birds and other wildlife, but it’s toxic to cattle and most grazing mammals. Bobwhite quail love the seeds.

Sources: Vogel, American Indian Medicine, 213.

Front Meadow Timbergrove Side

As you finish the tour, be sure to observe the flowering plants in the butterfly garden, the areas around the walls. Watch the diverse group of butterflies, bees and flies nectaring on the flowers and spreading pollen at the same time. This ensures seeds will form. These seeds drop on the ground and grow into next years’ wildflowers.