By Amy Grotta and Brad Withrow-Robinson, OSU Forestry & Natural Resources Extension
Last week, a large contingent of the OSU Forestry & Natural Resources Extension team traveled to the Gulf Coast of Mississippi for a biennial conference of natural resources Extension professionals. Besides the chance to exchange ideas with our colleagues from across the country, these meetings afford the opportunity to learn about the ecology and natural resources issues that define the geography of the meeting location.
We learned that the forests of Mississippi are quite diverse. They are defined by their topography, proximity to the coast, and (as in Oregon) landowner objectives. While on the surface they seem about as far from Oregon’s forests as you can get, there are some similarities to the forest systems and issues we have back home. We thought we’d share a bit about the interesting forests that we saw and learned about on our visit.
Low lying areas near the Gulf Coast are covered by slow moving water in bayous and swamps. There are a number of trees that are adapted to these inundated conditions, creating otherworldly forests. As you move farther inland, the salinity of the water decreases and the vegetation also changes. Marsh grasslands give way to bald cypress trees, which in turn become mixed with a variety of other trees adapted to standing water. Really the best way to explore these forests is by boat, which is what we did.
Many of these trees feature large buttresses at their base. I suppose this contributes to their stability in mucky conditions. Bald cypress is a deciduous conifer with strange “knees” that jut out of the water around them. The knees are a part of the tree’s roots, but their function is debated.
Pines in Lines
The Southeast produces more wood fiber than any other region in the U.S., and much of that is in southern yellow pine plantations on private forestlands. Southern yellow pine can refer to one of several pine species, depending on the location, but the biggest plantation species are loblolly and slash pine. They are fast-growing, and rotations can be as short as 25 years. We didn’t visit these plantation forests, but drove past some and heard various references to “pines in lines” throughout the conference. We learned that in light of declining pine markets, Extension services in the South are encouraging smaller private forest owners to manage mixed hardwood-conifer systems that have potential for diverse revenue streams. In addition, southern yellow pine plantations have been hard hit by hurricanes. These issues felt somewhat familiar to us.
Longleaf Pine Restoration
Longleaf pine forests and savannas once dominated the sandy lowlands of Mississippi and much of the South. Longleaf pine now covers only a tiny percent of its former area, having been replaced by agriculture and plantations of loblolly and slash pine. Eliminating fire (another familiar story) has allowed many hardwood trees and shrubs to fill in, altering the open habitat structure upon which many local wildlife species depend.
We visited the De Soto National Forest which is now actively restoring longleaf pine in many areas. Managers are harvesting older loblolly plantations, planting or leaving longleaf seed trees, and importantly, restoring fire to the landscape with an active prescribed fire program. This work is benefiting local species including the gopher tortoise and red cockaded woodpecker while also producing a significant amount of forest products.
We got a nice look at the effects of frequent prescribed fires in coastal wet longleaf pine savanna after 40 years of active restoration management at the Mississippi Sandhill Crane National Wildlife Refuge northeast of Biloxi.
Longleaf pine has an interesting fire adaptation strategy. It starts life in a “grass stage” which keeps the sensitive growing point below ground and safe from fire, generally for several years. Once it has built a strong root system, it puts on a growth spurt to get its buds up above the reach of fire.
So that’s our photo tour of the forests of southern Mississippi. In 2020, when this meeting comes to central Oregon (hosted by OSU Forestry & Natural Resources Extension), we’ll have a chance to showcase Oregon’s diverse forests to our national colleagues.