Click on the thumbnail to see a slideshow of some examples of the roots.

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Partially exposed root system of a mature longleaf pine along a roadcut in Thomas County, Georgia. Relationship between large taproot and primary lateral roots is well illustrated.
Exposed root system of a young longleaf pine seedling. Note that aboveground the tree is only about two feet tall while belowground the roots extend both outward and downward for several feet.
Tap root exposed on a young longleaf pine. Note that the tap root of this tree is a little over twice as long as the aboveground portion, providing valuable stability in these sandy soils.
A longleaf pine that was unable to develop a tap root because of hard ground causes this tree to become top heavy and fall over at about 5 feet tall. (See next slide.)
A longleaf pine that was unable to develop a tap root because of hard ground causes this tree to become top heavy and fall over at about 5 feet tall.
Exposed root system of a mature longleaf pine tree. Note that the size of many of the primary roots are as large as the tree's branches. Lateral roots have been documented extending outwards to 75 feet from the tree but average closer to 50 feet. Also note the number of smaller roots branching off the primary ones.
Historic picture illustrating the size of the tap root on a mature longleaf pine tree. Note the axe for scale.

(USDA Forest Service image.)
Category 4 hurricane force winds were enough to tip up this longleaf pine tree in Flomaton, AL, but not strong enough to uproot the tree's tap root (which is seen snapped off in this picture).
Feral (wild) hog beginning to root up a longleaf pine seedling. Longleaf pine roots provided a much needed source of carbohydrates for the hogs when other food was scarce. However, once the hogs developed an appetite for longleaf pine, they were effective in rooting them up, with one hog able to consume a 1/2 acre of seedlings per day. Hogs have been documented digging up roots as deep as six feet underground.

(Source: Wood hogs versus pine logs. USDA Forest Service Publication.)
Mounds of dirt are telling signs of belowground pocket gopher activity. These burrowing animals perform a valuable service in turning and aerating the soil. The gophers are stricktly vegetarians, eating mainly roots or tubers. In this picture, longleaf roots likely make up part of the diet.
Until recently, many longleaf pine stumps were harvested (as shown) and distilled into turpentine products. Such activities quite often destroyed the stump hole habitat needed by so many creatures.

(17-ton stump dozer lifts huge stump: Taylor County, Florida. Image number: c005640. Photographed April 3, 1947. Courtesy of Florida Photographic Archives.)

 

Longleaf Pine Roots

Longleaf has a reputation of slow growth during the seed and grass-stages.  However, while longleaf may demonstrate little growth aboveground, belowground a tremendous amount of activity is taking place.  Longleaf generally grows on dry sandy soils (although certainly can be found on a wide array of soil types).  In these dry, loosely arranged soils, it is advantageous for the tree to quickly establish a root system that finds deep lying soil moisture and provides anchorage.  During the first few years following germination, longleaf pine seedlings quickly develop an impressive root system.

Once longleaf pine starts height growth, their large bundles of needles cause them to become somewhat top heavy. Without a stout tap root in place, these trees can easily fall over.

As the tree continues to mature, both the lateral and tap roots continue to grow. In mature trees, roots radiate out laterally an average of 35 feet from the trunk (some roots may travel up to 75 ft). Longleaf differs from other pines in that the tap root is nearly as large in diameter as the tree's trunk, tapering gradually to depths (on average) of 10 to 15 feet.

Longleaf roots are high in carbohydrates and other nutrients. Because of their food value, various animals seek them out. Although relatively harmless to mature longleaf, pocket gophers excavate extensive caverns while feeding on the roots of longleaf pine and other plant species. At one time, wild pigs were very abundant in the southeast and their voracious appetite for longleaf roots resulted in countless acres of young trees being rooted up. When a longleaf pine tree dies, fires often consume the stump creating a hole roughly the dimensions of the tap root. The burned or rotted out root systems of these stumps create a myriad of tunnels ideal for various cold-blooded creatures.