Common Name: Mexican Pinyon

General Information

Pinus cembroides is a much-branched evergreen shrub or a tree with a rounded crown; it can grow up to 15 metres tall. The strongly tapering bole can be up to 30cm in diameter[].
Pinus cembroides is the common pinyon of Mexican commerce, being harvested in large quantities from the wild and traded[, ]. The tree is also harvested from the wild for local use as a medicine and source of materials.
Pinus cembroides is a very widespread and abundant species, although two of its subspecies (subsp orizabensis D.K.Bailey and subsp lagunae Rob.-Pass.) D.K.Bailey) are considered to be threatened. The species as a whole is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].

Known Hazards

The wood, sawdust and resins from various species of pine can cause dermatitis in sensitive people[].

Botanical References

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Range

Southern N. America - Arizona, New Mexico, Texas, south to central Mexico.

Habitat

Pinyon-juniper woodland, foothills, mesas, tablelands; at elevations from 700 - 2,300metres[]. Hot arid mountain slopes above 2,000 metres, with juniper and scrub oak[, ]. Usually found in poor, shallow, rocky or gravelly soils[].

Properties

Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	8.00 m
Growth Rate	Slow
Pollinators	Wind
Self-fertile	No
Cultivation Status	Wild

Cultivation Details

Pinus cembroides is a plant of warm temperate to subtropical regions of southern N. America. The climate is warm and dry, with annual precipitation varying from 380 - 650mm and a dry season of 7 - 8 months. Frost may occur at higher elevations in the interior, but is infrequent[]. The plant is not very cold-hardy, tolerating short periods with temperatures down to between -5 and -10°c[].
Pine species in general require a sunny position if they are to grow well and, whilst the different species have their own soil preferences, most will thrive in a light well-drained sandy or gravelly loam[, ]. Found in the wild on a variety of substrates, ranging from alluvial bajadas to volcanic rock, usually on scarcely developed soils[]. Dislikes poorly drained moorland soils[]. Established plants tolerate drought, succeeding in hot, dry positions[].
Leaf secretions inhibit the germination of seeds, thereby inhibiting the growth of other plants below the tree[].
A slow growing plant[, ], it takes 25 years from seed before cones are formed[]. The tree takes 250 - 350 years to reach full maturity[].
Seed cones maturing in 2 years, shedding seeds and falling soon thereafter, spreading, symmetric, ovoid before opening, broadly depressed-ovoid to nearly globose when open, 1--3.5cm[].
The cones open and shed their seed whilst still attached to the tree[].
This is one of several species of pine that have a mutualistic relationship with species of birds in the family Corvidae (in this case Jays and Nutcrackers) to disperse its seed. The birds have powerfull beaks which enable them to extricate the seeds and crack the shells. They store many of the seeds at some distance from the parent plant - some of these seeds never get eaten and can germinate and grow into new trees[].
Plants are strongly outbreeding, self-fertilized seed usually grows poorly[]. They hybridize freely with other members of this genus[].
This species is sometimes held to include a number of very similar species which are here treated as separate entities[, ]. See Pinus edulis, Pinus monophylla and Pinus quadrifolia. These species differ mainly in the number of leaves in a bundle[].
The sub-species P. cembroides orizabensis. D. Baill. has larger seeds than the type[].
Plants in this genus are notably susceptible to honey fungus[].

Edible Uses

Seed - the oily seed kernel is eaten raw, roasted, ground into a powder for making bread, cakes etc or made into a nut butter[, , , , , , , , ]. An excellent flavour[]. A good size, the seeds are up to 15mm long[]. Said to be the highest in protein and lowest in starch of all the piñons[]. The seed contains about 14.6% protein, 62% fat. 17.3% carbohydrate[]. This species provides a major source of seeds for sale in Mexico[].

Inner bark - only used in times of dire need[]. There are no more details but inner bark is often dried, ground into a powder and then used as a thickener in soups etc or added to cereals when making bread.

A vanillin flavouring is obtained as a by-product of other resins that are released from the pulpwood[].

Medicinal

The gum exuding from damaged areas of the tree is used to treat sore throats[, ].

Oil of turpentine, obtained from the oleo-resin of all pine trees, is antiseptic, antispasmodic, astringent, diuretic, rubefacient, stimulant and vermifuge[, ]. It is a valuable remedy used internally in the treatment of kidney and bladder complaints and is used both internally and as a rub and steam bath in the treatment of rheumatic affections[]. It is also very beneficial to the respiratory system and so is useful in treating diseases of the mucous membranes and respiratory complaints such as coughs, colds, influenza and TB[].
Applied externally in the form of liniment plasters, poultices, herbal steam baths and inhalers, it is a very beneficial treatment for a variety of skin complaints, wounds, sores, burns, boils etc[].

Agroforestry Uses:

Due to its adaptation to semi-arid environments and extensive range this is an important shrub or tree for aspects of land management, such as watershed protection, prevention of erosion, and as a shade tree in agro-forestry[].
The needles contain a substance called terpene, this is released when rain washes over the needles and it has a negative effect on the germination of some plants, including wheat[].

Other Uses

A tan or green dye is obtained from the needles[].

A gum pitch is used as a glue for waterproofing and repairing pottery[, ].
Oleo-resins are present in the tissues of all species of pines, but these are often not present in sufficient quantity to make their extraction economically worthwhile[]. The resins are obtained by tapping the trunk, or by destructive distillation of the wood[, ]. In general, trees from warmer areas of distribution give the higher yields[].
Oil of Turpentine consists of an average of 20% of the oleo-resin[] and is separated by distillation[, ]. Turpentine has a wide range of uses including as a solvent for waxes etc, for thinning and dissolving varnish and paints, a shoe polish, medicinal etc[, ].
Rosin is also obtained by distillation of pine resin. This is used in paper glue and soap manufacturing, as a constituent of varnishes and paints, and for coating the bows of stringed musical instruments such as violins[, ].
Pitch can also be obtained from the resin and is used for waterproofing, as a wood preservative etc[].

The wood is soft, light in weight, close-grained[]. It is of too small a size to be of much interest for commercial forestry, but it is sometimes harvested localy for use, mainly as posts[, ].
The wood is often used for fuel and is somewhat fragrant when burnt[].

Propagation

It is best to sow the seed in individual pots in a cold frame as soon as it is ripe if this is possible otherwise in late winter. A short stratification of 6 weeks at 4°c can improve the germination of stored seed[]. Plant seedlings out into their permanent positions as soon as possible and protect them for their first winter or two[]. Plants have a very sparse root system and the sooner they are planted into their permanent positions the better they will grow[]. Trees should be planted into their permanent positions when they are quite small, between 30 and 90cm[]. We actually plant them out when they are about 5 - 10cm tall. So long as they are given a very good weed-excluding mulch they establish very well[]. Larger trees will check badly and hardly put on any growth for several years. This also badly affects root development and wind resistance[].
Cuttings. This method only works when taken from very young trees less than 10 years old. Use single leaf fascicles with the base of the short shoot. Disbudding the shoots some weeks before taking the cuttings can help. Cuttings are normally slow to grow away[].