Key to the Gymnosperms of the Southeastern U.S. -
Key to the Pines (Pinus)
Twigs relatively smooth; needles 3-10 cm. long, in bundles of 2 only; bark without resin pockets


Bark on upper sections of trunk is reddish to red-brown, and in plates; seed cones persist on branches, are often long serotinous, and are usually armed with a small prickle -
Sand pine (Pinus clausa)

OR

Bark on upper sections of trunk is gray, and more or less smooth, appearing slick; seed cones tend to fall after maturity, are not serotinous, and are unarmed or bear a minute, deciduous prickle -
Spruce pine (Pinus glabra)

   
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