Be aware of the following:

Caprock Coulee

Nature Trail

National Park Service

U.S. Department of the Interior

Theodore Roosevelt National Park

Wildlife Poison Ivy Rattlesnakes

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the box when you finish hiking.

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Stairs
The Caprock Coulee Nature Trail is a 0.8 mile section of the Caprock Coulee Trail. 

This part of the trail shows the natural and geologic variety of the badlands. It also 

provides a rare look at a densely wooded area of the park.

When you reach the end of the nature trail, turn back for a trip totaling 1.6 miles. 

Or, if you are prepared for a longer hike, continue on the Caprock Coulee Trail for 

a hike of 4.1 miles. Wear sturdy shoes and appropriate clothing. Carry extra water 

and a trail map.

The pattern on the hillside is rivulet 

erosion. Rain carves a maze of 

channels over the face of the butte. 

These narrow rills merge to form a 

network of larger channels. 

2. Rivulet Erosion 

Caprock Coulee Nature Trail

1. Coulees 

Take a left where the trail forks. 

The trail to the right leads to the Buckhorn Trail.

Coulees are steep, narrow valleys 

like the one you are about to enter. 

Although they are formed by water 

erosion, coulees are usually dry in 

summer, except during thunderstorms. 

In the 1800s French fur trappers 

began referring to these valleys as 

“coulée” meaning “flow.” Since then 

the name has stuck.

Rivulet erosion is one of many never 

ending systems of erosion taking place 

in the badlands. With each rain shower, 

the land changes shape.
Dark purple chokecherries hang from 

these branches in late summer. Plains 

Indians enjoyed the fresh berries and 

also ground and dried them for winter 

use. Beware! The leaves, roots, and 

seeds are poisonous.

4. Chokecherry (Prunus virginiana)

Look for the differences in the 

vegetation patterns on the buttes 

around you. Notice the moist, cool, 

north-facing slopes supporting stands 

of juniper and other woody plants. 

South-facing slopes receive more 

direct sun rays making them hotter and 

drier. They are the ideal place for more 

desert-like plants. Explore these two 

plant communities on the trail ahead.

5 Badlands Slopes 

Rainfall influences the amount and 

type of plants that can grow in an 

area. This region receives only about 

15 inches of precipitation each year, 

making it well suited for grasses. 

Prairie grass is an important food 

source for grazers like bison, deer, and 

other wildlife.

3. Grass 

green needle grass

(Bouteloua gracilis)

needle-and-thread

(Stipa comata)

western wheatgrass

(Agropyron smithii)

North

shady, cool, moist

South

sunny, hot, dry
On the slope to your left is a thin black 

seam of lignite coal. Coal forms when 

vegetation is buried and subjected to 

great heat and pressure. Coal seams 

and other fossils tell us this region was 

once a lush, thickly vegetated swamp.

8. Lignite

Silver-green sagebrush is a common 

sight throughout the western United 

States. Here, it grows abundantly on 

terraces above the Little Missouri 

River. Look closely at the leaves on 

7. Sagebrush

several of the bushes as you walk along 

the trail. You should find three different 

shapes belonging to three different 

species. Notice how each species has a 

unique smell.

silver sagebrush

(Artemisia cana)

big sagebrush

(Artemisis tridentata)

fringed sagebrush

(Artemisia frigida)

The thin layers of rust-red rock on 

the butte in front of you are ironimpregnated sandstone. Because they 

are harder than the soft gray sediments 

that make of up the rest of the butte, 

they erode more slowly. Notice how 

these hard layers form shelves that 

protect soft sediments below. This type 

of erosion, called differential erosion, is 

the main shaping force of the badlands. 

6. Differential Erosion 
The blue-grey sediment on the hillside 

across the coulee is bentonite clay. 

Bentonite contains 

volcanic ash and is 

common throughout the 

badlands. It can absorb 

several times its volume 

in water and has many 

industrial uses. After 

heavy rains or when 

soaked by melting snow, it 

expands and flows down 

hillsides. Notice the wildlife trails 

crossing the steep bentonite slope.

9. Bentonite

Prickly pear cactus (Opuntia 

polyacantha) grows in clusters on the 

hill in front of you. It is one of few 

cactus species to grow this far north, 

and one of four in the park. Prickly 

pear is adapted to withstand periodic 

droughts. Its leaves have been reduced 

to spines to help preserve moisture and 

protect the plant.

10 Prickly Pear Cactus 

Light-colored pieces of petrified 

wood dot the far hillside. They are the 

fossilized remains of trees that grew 

here 55 million years ago. Parts of the 

trees were covered by sediment which 

prevented decay. Ground water slowly 

filled the cell spaces with minerals. The 

minerals hardened, preserving the trees 

as rocks. Much later in time, erosion 

exposed the petrified wood. The trees, 

likely cypress or magnolia, are further 

evidence of the area’s swampy past. 

11. Petrified Wood 

Leave No Trace

Help preserve the park for future generations by leaving everything just the 

way you find it. Remember - all natural features of the park are protected. 
Across the coulee to the right is a 

small slump. Notice its layers are 

diagonal instead of horizontal. Unlike 

a landslide where earth and rock break 

up as they tumble down, slump blocks 

remain whole as they slide. Match the 

colors in the slump to the rock layers 

on the wall above to find where the 

slump came from. 

Right: an example of slumping visible 

from the park’s North Unit Scenic Drive. 

12. Slump

The vertical “pipes” in the coulee walls 

are formed by a type of erosion called 

piping. Rainwater enters small surface 

openings, like rodent burrows or tree 

root tracks, and saturates the ground. 

The saturated ground then collapses, 

forming a pipe. The size of some pipes, 

up to several feet deep and wide, makes 

them a significant force of change in 

the badlands.

13. Piping

The next part of the trail explores 

a north-facing slope. Notice the 

difference in temperature. 

Animals and hikers alike 

appreciate these pockets of 

vegetation for the shade and 

protection they provide. 

Three types of juniper grow 

on north-facing slopes. See if 

you can locate them all.

14. North-facing Slopes

Rocky Mountain juniper

 (Juniperus scopulorum)

 - upright tree shape

 - scale-like needles

creeping juniper

(Juniperus horizontalis)

- low ground cover, scale-like needles

common juniper

(Juniperus communis)

- shrub size, sharp needles
Small sources of water, like the one 

you just passed, become gathering 

places for wildlife. Seeps and springs 

draw bison, coyotes, and other animals 

looking for a drink. Look for signs of 

their presence, such as tracks or scat, 

on the trail.

17. Wildlife Tracks

Forest “litter,” made of fallen leaves, 

trees, and other dead plant matter, is 

an important part of the north-slope 

habitat. Many animals use forest litter 

for food, shelter, or nesting places. As 

time passes, the dead plant materials 

decay into the ground to nourish a new 

cycle of plant growth.

18. Forest Litter 

Rabbitbrush is the last flower of the 

season to bloom, hinting at the arrival 

of winter. During the hot summer, 

rabbitbrush provides shade and shelter 

for small animals. In the winter it serves 

as food for deer and elk.

15. Rabbitbrush

A slump that begins on the butte 

ahead has completely blocked the 

coulee. Water from the seep above you 

saturated a layer of bentonite clay. The 

force of gravity on the wet, slippery 

clay was too much and a section of land 

gave way, sliding into the coulee. While 

the seep water is unfit for human use, 

animals welcome it in this semi-arid 

country. Watch your footing - seep 

water can make this area slippery.

16. Active Slump

deer

coyote

bison

mountain lion

• 3.5 - 5 in. wide

• foot pad has 3 

 bottom lobes

• claw marks usually 

 absent

• circular shape and 

 asymmetrical with a 

 leading toe

• 2.25 in. wide

• claw marks present

• oval shaped and symmetrical 

• 4.5 -6 in. long

• 3 in. long
This trail brochure was printed using your fee dollars. 

Thank you for your support!

EXPERIENCE YOUR AMERICATM

You have reached the end of the 

Caprock Coulee Nature Trail. The 

shortest way back to your car is to turn 

around here. If you continue ahead 

you will have to hike another 3.3 miles 

to return to where you started. Only 

continue if you are prepared with extra 

water, appropriate clothing, and a map.

21. Trail’s End

The bright-colored splashes on the 

tree trunks are lichens (pronounced 

li-kens). Lichens consist of two 

different organisms – fungi and 

algae. The two live together in a 

balanced relationship as if they were 

one organism. The alga makes food, 

while the fungus gathers and holds 

water for both organisms. Lichens 

20. Lichens

We hope you enjoyed your hike! 

Please return this brochure to the box at the start of the trail.

Download this brochure at 

www.nps.gov/thro/planyourvisit/hiking-and-trail-information.htm

can be indicators of changes in 

the environment; some species are 

sensitive to changes in air quality.

Green ash grows in ravines and 

coulees throughout the park. 

Songbirds build their nest in the ash 

tree’s shady branches. Bison use trees 

as scratching posts. Can you feel 

where their scratching has rubbed the 

bark smooth?

19. Green Ash