Common Name: Piñon de Nelson

General Information

Pinus nelsonii is an evergreen tree with a rounded, dense crown of upcurved branches; it usually grows up to 6 - 7 metres tall, but can occasionally reach 10 metres. The bole can be around 20 - 30cm in diameter[, ].
The plant is harvested from the wild for local use as a food.
Pinus nelsonii is by all accounts a rare pine with a scattered occurrence largely limited to limestone outcrops. Its total population almost certainly numbers fewer than 10,000 mature trees, mostly in (sub)populations of a few hundred individuals. It is thought to be in decline due to habitat disturbance and loss associated with increased cattle ranging and incidence of destructive fires associated with this type of land use. The plant is classified as 'Endangered' 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

, ,

Range

Southern N. America - northeast Mexico (Nuevo León, San Luis Potosí and Tamaulipas).

Habitat

Open conifer woodland mixed with a xerophytic shrub vegetation that includes cacti and agaves, growing in fairly flat, very dry areas, often on limestone; at elevations from 1,800 - 2,500 metres[].

Properties

Conservation Status	Endangered
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	6.00 m
Growth Rate	Slow
Pollinators	Wind
Self-fertile	No
Cultivation Status	Wild

Cultivation Details

Pinus nelsonii is a plant of arid and semi-arid regions of northern Mexico where the mean annual precipitation ranges from 300 - 600mm, falling mostly in the summer during brief thunderstorms. It is not a very cold-hardy plant, being able to tolerate short periods with temperatures down to around -10°c iwhen it is fully dormant[, , ].
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[, ]. Dislikes poorly drained moorland soils[]. Established plants tolerate drought[] and are very resistant to maritime exposure[].
Only one specimen of this genus is known to be growing in Britain. Planted at Kew in 1910, it was 10 metres tall in 1969[]. The plants often develop as multi-stemmed shrubs[].
The cones open and shed their seed whilst still attached to the tree[].
Plants are strongly outbreeding, self-fertilized seed usually grows poorly[]. They hybridize freely with other members of this genus[].
Seedlings have only juvenile foliage for several years[].
The cylindrical seed cones are 6 - 12cm long, 4 - 5cm wide, taking two growing seasons to ripen, then retaining their seeds until they are removed by birds, mainly the gray-breasted jay Aphelocoma ultramarina[].
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 in this genus are notably susceptible to honey fungus[].

Edible Uses

Seed - raw or cooked. Quite tasty[]. An oil-rich seed with a hint of resin in the flavour. Fairly large, the seed is around 10 - 12mm long and 8mm wide[, ].

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

Medicinal

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:

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[].

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[].

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[].