Armand pine or Chinese white pine is native to a wide swath of China, Taiwan, and Burma/Myanmar. It is a widespread and common species, used economically for construction, furniture, and wood fibre.
What it is not, or rather should not be, used for is pine nut production. About twenty different species of Pinus have potential to be used for pine nut harvesting, though most come from Pinus koraiensis, Pinus sibirica, Pinus pinea, and Pinus gerardiana. If the seeds of Pinus armandii are introduced into the food supply, consumer complaints about pine nut syndrome or pine mouth skyrocket. To read one foodie’s account of it, see “Ever heard of ‘pine nut syndrome’? Neither had I, until I got it” from Robin Abcarian of the Los Angeles Times.
Here’s Wikipedia’s write-up on its pine nut page:
Pine nuts can cause taste disturbances, lasting from a few days to a few weeks after consumption. A bitter, metallic, unpleasant taste is reported. There are no known lasting effects, with the FDA reporting that there are “no apparent adverse clinical side effects”. This phenomenon was first described in a scientific paper in 2001. Publications have made reference to this phenomenon as “pine nut syndrome” (PNS), or as “pine mouth”.
The Nestlé Research Centre has hypothesized that nuts from Pinus armandii, which occurs mostly in China, are the cause of the problem. The nuts of this species are smaller, duller, and more rounded than typical pine nuts. A 2011 study found results consistent with this hypothesis and also suggested that chemicals used in the shelling process might be responsible.
Metallic taste disturbance, known as metallogeusia, is typically reported 1–3 days after ingestion, being worse on day two and typically lasting up to two weeks. Cases are self-limited and resolve without treatment. Möller has postulated a hypothesis—to explain both the delayed onset of, and the long-lasting nature of, the metallic or bitter taste sensation—involving a well-known physiological process known as enterohepatic recirculation (EHR), which Möller describes as a “remove-recycle-repeat” digestive process where toxins could potentially circulate through the digestive tract multiple times.
Pinus armandii grows to heights of about 35m (115 ft.) tall. It typically occurs on thin, rocky soils at elevations between 900 and 3500m (3000-11500 ft.). Associated forest species include firs (Abies), spruces (Picea), and Douglas-firs (Pseudotsuga). Asian Flora has additional photos of the species, including some in habitat: Pinus armandii.
It is a IUCN Red List species of least concern.