The Eastern red cedar rapidly colonizes and takes over recently opened-up habitats. Shaw Nature Reserve had a long history, previous to the purchase of the property by the Missouri Botanical Garden in 1925, of logging, grazing, and agriculture. The many cedars here are a sign of past ecological disturbance.
With their dense, year-round shade and acidifying needle duff, cedars make the ground beneath them unsuitable for the growth of many other plant species and for the animals that depend on these plants for survival. Reducing the cedar population makes room for these other species to exist. Many attractive wildflowers that were once common at Shaw Nature Reserve became rarer as the cedar population grew in recent years.
Before Euro-American settlement, the native upland vegetation of this part of Missouri was much more open than it is today. The land was covered with a sort of prairie studded with oak and hickory trees called savanna by ecologists. Only in the moistest, most protected sites, such as river flood plains and shaded valleys, did the closed-canopy woodlands we think of as "normal" forest occur.
Native Americans that lived here for at least 10,000 years before the arrival of settlers from Europe were truly a part of their environment. They knew the plants and animals of their surroundings well, and had learned not only how to utilize these species for food, fiber, medicine, etc., but also knew how to manage their environment to favor these species. The major management tool in "presettlement" times was annual burning. During dry spells, from late fall through early spring, the Native Americans set fire to the fields and savannas, which could then spread unchecked for miles and miles. In wet years, fires burned irregularly, often not even entering the shaded areas.
The thinning of cedar stands at Shaw Nature Reserve is an ecological management tool which complements use of fire, and is meant to set back ecological changes set forth by the arrival of Europeans to this area in the early 1800s. These practices will enable us to regain the pristine beauty and biological richness of the Reserve's relatively tiny island of natural vegetation in a sea of agriculture and development.