VISITOR INFORMATION 



Grand Gulf State Park 

 Route 3, Box 3554 

 Thayer, MO 65791 

 417-264-7600 



www.mostateparks.com/grandgulf.htm 



Mammoth Spring State Park 

 P O. Box 36 



Mammoth Spring, AR 72554 

 870-625-7364 



www.arkansasstateparks. com/parks/park. asp?id=25 



fact it IS considered a wetland species. 



In 1921 a tornado churned 

 through the area, uprooting trees and 

 blowing some of them into the 

 canyon. Downed trees washed into 

 the entrance of the underground 

 cave, largely blocking it. Nowadays, 

 after heavy rains, additional debris 

 accumulates in the cave entrance, and 

 Grand Gulf can fill quickly with 

 water, sometimes to a depth of nearly 

 a hundred feet. Eventually, though, 

 the ponded water does drain away, 

 and in fact the streambed is often dry. 

 The cave entrance, once open to ex- 

 ploration, remains, by most accounts, 

 impenetrable to human adventurers. 



In 1967, Tony Aid, then a high 

 school student from nearby West 

 Plains, placed dye in the water of 

 Bussell Branch where it entered the 

 underground cave. After several days, 

 the dyed water appeared more than 

 seven miles to the south in Mam- 

 moth Spring, Arkansas. 



Fed in part by the water from 

 Grand Gulf, Mammoth Spring flows 

 at an average of 9.78 million gallons 

 an hour. Emerging with a constant 

 temperature of 58 degrees, the spring 

 is the source for beautiful Spring 

 Lake, a main attraction of Mammoth 

 Spring State Park. Because the spring 

 vent is eighty feet below the surface of 



the lake, however, there's no bubbhng 

 springwater to be seen. From the lake, 

 which was formed by damming, the 

 waters join Spring River, popular 

 with trout anglers. 



In the nineteenth century a town 

 called Head of the River (now called 

 Mammoth Spring) arose near the 

 spring. A gristmill was built there to 

 tap the spring's water for power. In 

 1886 the railroad line came to town. 

 The original train depot is now an 

 added attraction in Mammoth Spring 

 State Park. 



Robert H. Mohlenbrock is a distin- 

 ^iiished professor emeritus of phut biology at 

 Soiitlicni Illinois Uiiiivrsity Carhoiidalc. 



Habitats 



Dry forest Several oaks dominate 

 the dry rim of Grand Gulf, including 

 blackjack oak, chinquapin oak, 

 northern red oak, post oak, scarlet 

 oak, and southern red oak. Other 

 trees include black cherry, red cedar, 

 shagbark hickory, and winged elm. 

 Among the shrubs are dwarf hack- 

 berry, farkleberry (a kind of blueber- 

 ry), and (though a wetland species) 

 ninebark. A common low-growing 

 plant is poverty grass, readily recog- 

 nized by the curled-up leaves at its 

 base. Spring wildflowers include 

 downy phlox, pussytoes, rose verbe- 

 na, and stiff bluets. Among the sum- 

 mer and autumn bloomers are blue 

 wood aster, goat's rue, pencil 



flower, scurf-pea, spreading aster, 

 woodland sunflower, and a wiry- 

 stemmed member of the mint family 

 known as dittany. 



Where the cliffs make enough 

 shade, the moister conditions sup- 

 port black gum, Carolina buckthorn, 

 flowering dogwood, persimmon, red- 

 bud, shagbark hickory, white ash, and 

 white oak. 



Canyon bottom If you make it down 

 to the bottom of Grand Gulf (there is 

 a trail with stairs), you'll find Ameri- 

 can elm, bitternut hickory, black wil- 

 low, blue beech, box elder, cotton- 

 wood, honey locust, pawpaw, and 

 sycamore. Spicebush is the most 



common shrub; among the more 

 scattered ones is American bladder- 

 nut. Wildflowers along the stream 

 include bitter cress, ditch stonecrop, 

 hooked buttercup, pale corydalis, 

 seedbox, small-flowered crowfoot, 

 white avens, and various kinds of 

 smartweed. 



Lake The water in Spring Lake is so 

 clear that waterweed, an aquatic 

 plant, is visible floating just beneath 

 the surface. Watercress, a common 

 plant in springwater, is plentiful. Nu- 

 merous smartweeds, as well as false 

 nettle, nodding beggar ticks, and wa- 

 ter purslane grow in muddy areas 

 along the shoreline. 



February 2006 N.MURAl lllsIOl(.^ 



