Pines do better than angiosperms in these nutrient-poor soils. Pine needles are also an a adaptation to reduce water loss. And they re the perfect shape for wind-pollinated plants, like conifers. The major natural disturbances in the pine forest are fire, wind, and man. The combination of fires and sandy soils are the most important factors explaining the dominance of pine forests throughout the south.
Fire is essential in maintaining pine forests.
In the absence of disturbance by fire, hardwoods may replace the pines by gradually getting a foothold in the forest understory. Not many species can tolerate the physical conditions on the floor of the pine forest. The decaying pine needles produce a very acid leaf litter. The few deciduous species that can tolerate these conditions, and grow in the understory of the pine forest, grow much faster than the pines. Whereas angiosperm seedlings can establish and grow in the pine forest, pine seedlings need so much light that they cannot grow well in the shady understory of the typical hardwood forest.