Haploxylon

pine subgenus

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June 29, 2026

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The subgenus Haploxylon, also known as soft pines, is one of two subgenera within the Pinus genus, which comprises about 115 species of evergreen conifers in the family Pinaceae. Soft pines are characterized by having a single fibrovascular bundle in their needles. Their timber is relatively soft, and their needles are typically found in bundles of five, though sometimes in bundles of one to four. The cones of soft pines have scales that lack prickles, and they contain little resin. Their wood is fine-grained with thin, pale sapwood, and the sheaths of their leaf clusters are deciduous. Examples of soft pines include white, sugar, and piñon pines.1

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pine
Physical description and natural history
…Pinus to contain two subgenera: Haploxylon, or soft pines, which have one fibrovascular bundle in the leaves, and Diploxylon, or hard pines, which have two. Soft pines, such as white, sugar, and piñon pines, have relatively soft timber, needles in bundles of five (less commonly, one to four), stalked cones…
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…Pinus to contain two subgenera: Haploxylon, or soft pines, which have one fibrovascular bundle in the leaves, and Diploxylon, or hard pines, which have two. Soft pines, such as white, sugar, and piñon pines, have relatively soft timber, needles in bundles of five (less commonly, one to four), stalked cones…
Read More