There are three main subgenera of Pinus
, the subgenus Strobus
or soft pines), the subgenus Ducampopinus
and Lacebark pines), and the subgenus Pinus
, or yellow or hard pines). This classification into the three subgenera is based on cone, seed and leaf characters:
- Subgenus Strobus Scale without a sealing band. Umbo terminal. Seedwings adnate. One fibrovascular bundle per leaf.
- Subgenus Ducampopinus Scale without a sealing band. Umbo dorsal. Seedwings articulate. One fibrovascular bundle per leaf.
- Subgenus Pinus Scale with a sealing band. Umbo dorsal. Seedwings articulate. Two fibrovascular bundles per leaf.
Notice that in many respects, subgenus Ducampopinus is intermediate between (and possibly ancestral to) the other two subgenera. In many classifications, it is combined into subgenus Strobus, but it could with equal justification have been included in subgenus Pinus (as was done in an early classification by the Californian botanist J G Lemmon in 1888), yet it does not sit comfortably in either so is best treated as a third subgenus in its own right. In general, cone and cone scale and seed morphology and leaf fascicle and sheath morphology are emphasized and this seems to result in a classification that has subsections of pines that are understandable and usually readily recognized by their general appearance. Pines with one fibrovascular bundle per leaf, i.e. subgenera Strobus and Ducampopinus, are known as haploxylon pines, while pines with two fibrovascular bundles per leaf, i.e. subgenus Pinus, are called diploxylon pines. Diploxylon pines tend to have harder timber and more amounts of resin than the haploxylon pines.
Subgenus Strobus: white or soft pines
- Section Quinquefoliae (section Strobus): white pines
- Subsection Strobi: North America, Central America, Europe and Asia
- Subsection Cembrae: Europe, northern Asia, western North America
Subgenus Ducampopinus: Pinyon, Lacebark and Foxtail Pines
- Section Parrya
- Subsection Nelsonianae - northeastern Mexico
- Subsection Krempfianae - Vietnam
- Subsection Gerardianae - Lacebark pines, Central Asia
- Subsection Rzedowskianae - big-cone pinyons, Mexico
- Subsection Cembroides - Pinyons (Piñons), Mexico, southwest United States
- Subsection Balfourianae - Foxtail pines, southwest United States
Subgenus Pinus - yellow or hard pines
- Section Pinus - mostly in Europe, Asia, except for P. resinosa in northeast North America and P. tropicalis in Cuba.'''
- Section Pinea - Mediterranean pines
- Subsection Pineae
- Subsection Pinaster
- Section Trifoliae - American hard pines
- Subsection Leiophyllae - Mexico, southwestern United States
- Subsection Australes - North America, Central America, Caribbean
- Subsection Contortae - North America
- Subsection Oocarpae - Central America, Mexico, western United States.
- Subsection Ponderosae - Central America, Mexico, western United States, southwest Canada.
Tree of Life Web
favors classification of Ducampopinus
species in Strobus
NCBI Taxonomy server files Ducampopinus species above as Strobus.