Editing Pinus echinata (section)

== Genetics ==
The shortleaf pine is a [[diploid]] organism that has twelve pairs of chromosomes. The genome of the shortleaf is comparatively similar to that of other pine species. The C value of the shortleaf pine, or the amount of DNA of a species chromosome, is 21.73 pg when measured utilizing laser flow cytometry.<ref name="Stewart-2016"/>

The genome of the shortleaf pine is not sequenced; however, loblolly pine genomic information can be used in comparative genetic studies regarding the shortleaf pine.<ref name="Stewart-2016"/>

The [[United States Department of Agriculture (USDA), USA|United States Department of Agriculture (USDA)]] launched a genetic improvement program in the 1960s that aimed to increase the genetic diversity of the species, which is crucial for effective restoration of the species, by breeding trees and conducting progeny tests. This program posed inadvertent effects, as it opened the opportunity of crossbreeding with the loblolly pine. Fast growth is a desirable trait among trees, and this is usually a characteristic of hybrid trees; in turn, breeders are inclined to select these traits. Shortleaf pine orchards are also often adjacent to loblolly pine orchards, which could cause hybrid breeding to occur as well.<ref name="Stewart-2016"/>