Over Christmas holiday break, our kids and grandkids came to visit and we took everyone on a walk on a nature preserve near our house. I pointed out the various plants as we walked along the trails, as I am wont to do.
I showed them the longleaf pines (Pinus palustris) (also known as southern yellow pine) growing there and how their growing habits make them more tolerant of frequent fires. Unlike other pines, they start out with a grassy stage for a couple of years when they develop a deep root system. If a fire passes during this stage, they only lose that year's needles and can easily start growing again. Once they start growing vertically, they grow quickly (up to five feet a year!) and do not put out any side branches for a year or more. Again, if fire passes through, they have only topknots of needles and don't provide much ladder fuel for the fire to climb higher. Their buds are covered with a dense layer of white hair, and their bark is thick. When they finally produce side branches, they are shorter than branches of other pines and point upward. Most other pine seedlings grow into a pyramid shape, like Christmas trees with broad, horizontal lower branches.
Young longleaf pines can grow up to five feet a year to keep their tops, where new growth occurs, above passing ground fires. With no branches to ignite, a dense covering on its buds, and a thick-barked trunk, a tree this size might just lose its needles in a fire and then continue to grow soon after.
A longleaf pine forest that has experienced periodic ground fires will have a lovely park-like feeling with a wealth of interesting undergrowth that would be crowded out in a weedier environment. This environment is important for many species of Florida's wildlife including the endangered red cockaded woodpecker.
These pines are a good drought-tolerant choice for urban landscapes because of their fast growth and their narrow habit. Also their deep root system provides more wind-resistance than other pines. If you have a sandy, sunny spot on your property, plant some of these interesting native pines.
How Grassy is the Grass Stage?
What I realized after our Christmas walk is that a dark green grassy plant, which had been growing on the side of our septic drainfield mound* for more than a year, was a longleaf pine. Finding it there surprised me because most of the pines in the immediate vicinity are loblollies (P. taeda). I wasn't on the lookout for longleaf pines in my yard and the grassy stage really did look like a grass or a rush. I transplanted it to a sunny, sandy spot in the front meadow. I'm not sure the transplant will take because I didn't want to dig a deep hole into the drainfield to get all of its roots, but we couldn't leave it there. (Update: This pine was slow to get started, but it has survived and has grown to about 5 feet tall in 2014.)
I hope that while you are out in the yard working on gardening projects that Mother Nature will provide you with some surprises, too. If she does, let me know. Happy gardening in 2009!
For more information on longleaf pines click this link:
*We have let the septic drainfield mound on the side of our back yard become a meadow, but we remove all the trees that sprout because their deep root systems will damage the drainfield. Since it's a drainfield, it was built with sandy soil to achieve the best drainage. This is produces a harsh, desert-like environment and the irrigation necessary to keep turf grass healthy is excessive. The previous owner had planted the mound with St. Augustine turf grass that did not do well at all, but other more drought-tolerant plants do better and it's the perfect environment for longleaf pines. Go to the meadow page to see how our meadows have developed over the last four years.
Ginny Stibolt moved to northeastern Florida in 2004 and even though she's a botanist and lifelong gardener, Florida gardening was a shock. She started writing The Adventures of a Transplanted Gardener columns for the Times Union newspaper in Jacksonville. This is one of those columns archived here on Floridata.com for your enjoyment. Now she's written three Florida garden books published by University Press of Florida: Sustainable Gardening for Florida, 2009; Organic Methods for Vegetable Gardening in Florida with Melissa Contreras, 2013, and The Art of Maintaining a Florida Native Landscape, 2015. Check out her blog for the latest news and articles: www.Green GardeningMatters.com