The Magnificence of Old Growth
the trees. A single large tree can add more than two tons of wood to the forest floor when it falls. Fallen trees decompose slowly and retain moisture during dry spells.
Downed logs are beneficial to at least 35 species of birds, bats, snakes, salamanders, skinks and frogs.
Not all the dead wood is on the ground. In Missouri old-growth forests about one out of every 10 standing trees is dead. Some standing dead trees (called snags) are completely intact; others are just stubs left standing after their tops have broken out. They remain standing for years.
Snags and the cavities they contain provide room and board for a host of other wildlife species. The habitat created by snags and fallen logs is not unique to old-growth forests, but old-growth forests typically have more of it than younger forests do, and the large snags and large fallen logs in old-growth forests persist for many decades as they gradually decompose.
In time, high winds, heavy snow and ice damage all leave their mark on old-growth forests. Such disturbances are unavoidable over a century or two. Severe weather can rapidly change the appearance of an old-growth forest and add large volumes of dead wood to the forest floor.
A 1994 ice storm at Kirksville in northern Missouri severely damaged about 7 percent of the trees in the nearby Dark Hollow old-growth tract. Overnight that one event increased the accumulated dead wood on the forest floor by 25 percent. For many years to come that forest will be less prone to ice or wind damage because the most susceptible trees are already down, and the hardy ones survived. In time the forest will fill in the canopy gaps with new branches and new trees as it renews itself once again
Old Growth Sites
- The best way to discover more about old-growth forests in Missouri is to walk in one. Listed here are some sites to visit. Each is unique, from the wet bottomlands of Big Oak Tree State Park to the fertile slopes of Engelmann Woods to the rocky hills of Roaring River State Park. The Directory of Missouri Natural Areas includes locations of other old-growth tracts, as well as many other interesting natural areas to visit. For a copy of the directory, write to Natural History, Missouri Department of Conservation, P.O. Box 180, Jefferson City MO 65102-0180.
- Big Spring Pines Natural Area (U.S. Park Service) is about one-half mile south of Big Spring near Van Buren in Carter County. White oak, black oak, scarlet oak and shortleaf pine are abundant in the overstory. The area offers a unique old-growth mixture of shortleaf pine and oaks and lies within the Ozark National Scenic Riverway.
- Engelmann Woods (Conservation Department) is located about five miles northeast of Labadie on Highway T in Franklin County. This area is in the Missouri River hills and overlooks the river valley along its north border. Sugar maple, red oak, chinkapin oak and white ash dominate the overstory. The area is noted for spring wildflowers and fall colors; the largest trees are over 30 inches in diameter and over 100 feet tall.
- Dark Hollow Natural Area (Conservation Department) is within Union Ridge Conservation Area, north of Green City in Sullivan County. Access is by foot; a map is advisable. White oak, red oak, basswood and hickories are abundant. Some sections show serious damage from a 1994 ice storm.
- Big Oak Tree Natural Area (Department of Natural Resources) is within Big Oak Tree State Park. This unique bottomland oak forest includes nine state champion trees (largest of the species in Missouri) and is sometimes called the "Park of Champions." Some trees exceed 140 feet in height. The area is a great site for bird watching.
- Mudlick Mountain (Department of Natural Resources) is located within Sam A. Baker State Park in Wayne County. The white and black oak forest grows on ancient igneous (volcanic origin) rock. This is one of the largest high-quality old-growth tracts in Missouri, though it was damaged by a tornado in 1985.
- Roaring River Cove Hardwoods (Department of Natural Resources) is in Roaring River State Park near Cassville in Barry County. Accessible by foot, this secluded site has numerous white oaks, black oaks, red oaks and hickories. Some trees are more than 250 years old, but in general trees on this dry site are smaller than on more fertile sites, such as Engelmann Woods.