Common Name: Monterey Pine

General Information

Pinus radiata is an evergreen tree with a dense crown; it can grow up to 55 metres tall. The bole is more or less straight, usually up to 150cm in diameter, occasionally to 250cm[].
Extensively cultivated for timber in warm temperate zones, especially in New Zealand, and also at higher elevations in the tropics, this is the most widely cultivated of all tree species. The tree is also often grown as an ornamental and to provide shade and shelter from strong winds[, , ].
Although very widely cultivated, wild stands of Pinus radiata have been severely reduced in the wild and are threatened by logging, feral goats, an introduced alien pathogen (pitch canker fungus), and competition from other trees in the absence of periodic fires. The plant is classified as 'Endangered' in the wild in the IUCN Red List of Threatened Species(2013)[].
Pinus radiata is widely used in forestry and has escped from cultivation, becoming naturalized and invasive in several countries, notably Australia, New Zealand, Argentina, Chile, Hawaii (USA) and South Africa. It is a prolific seed producer that reproduces at a young age, grows very rapidly and has seeds that may be stored in serotinous cones for many years. With its rapid growth and the high levels of litter that accumulate below, native species are outcompeted and reduced diversity has been recorded in areas where it has become invasive[].

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

South-western N. America - California, northern Mexico (Baja California, Guadalupe Island).

Habitat

Found only in a narrow belt a few kilometres wide near the California coast, in dry bluffs and slopes below 300 metres[, ].

Properties

Weed Potential	Yes
Conservation Status	Endangered
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	50.00 m
Growth Rate	Fast
Pollinators	Wind
Self-fertile	No
Cultivation Status	Cultivated, Ornamental, Wild

Cultivation Details

Monterey pine is a plant of the semi-arid, warm temperate zone of coastal southern California and is extensively cultivated in warm temperte zones and in tropical areas above 1,200 metres. In its native range the cold ocean water moving down the Californian coast substantially influences the local climate, raising humidity, tempering heat from the sun and causing almost daily summer fogs. On a rare clear day in summer temperatures can quickly rise to 40°c, coming down to only 15°c on the next foggy day[]. Rain fall is erratic, fog drip providing most of the moisture to the soil and the trees[]. In cultivation, the plant grows best in areas where annual daytime temperatures are within the range 18 - 30°c, but can tolerate 7 - 40°c[]. When dormant,it can survive temperatures down to about -15°c, but young growth can be severely damaged at -1°c[]. Trees are somewhat frost-tender when young[]. It prefers a mean annual rainfall in the range 650 - 1,200mm, but tolerates 330 - 1,600mm[]. It can grow with a dry season of up to 6 months[].
Grows best in a sunny position[]. Thrives in a light well-drained sandy or gravelly loam[, ]. It grows best on deep, well-drained, neutral to acid soils[]. Dislikes poorly drained moorland soils[]. Prefers a pH in the range 5.5 - 6.5, but can tolerate 4.5 - 7.5[]. Established plants tolerate drought[]. Very resistant to maritime exposure[], the leaves can be badly burned by cold dry winds but this does not seem to affect growth[]. Mature trees produce a broad heavy crown and are somewhat likely to be blown down in severe gales[]. The plant tolerates relatively high levels of air pollution[].
A fast-growing tree[]. Growth can be exceptionally fast, after an initial phase of 2 - 5 years, plants have a growth rate of up to 2 metres a year[].
Pollen production starts when trees are 5 - 6 years old, and female flowering starts around the same age. Female cones take 2 years to mature. Mature cones are 8 - 17cm long, they may remain closed on the tree for up to 40 years, only opening after the heat of a forest fire followed by rain[, , ].
A short-lived tree in the wild, where it rarely lives longer than 100 years[]. It grows larger in cultivation than it does in the wild[].
Plants are strongly outbreeding, self-fertilized seed usually grows poorly[]. They hybridize freely with other members of this genus[].
Plants can produce new shoots from reasonably old wood so the lower branches can be cut back to produce a hedge-like effect[].
Plants in this genus are notably susceptible to honey fungus[].

Edible Uses

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

The seeds of all Pinus species are more or less edible, and some are of good size and make very tasty and nutritious foods, often eaten in quantitiy. Others can be less desireable, either having a strongly resinous flavour, being bitter or, more commonly, rather too small and fiddly to make it very worthwhle even trying to eat them,
We have no specific information of the desireability of this species, though they are rather small (the size given includes the shell)[].
The dark brown seed is around 6mm long[].

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:

Monterey pine is very tolerant of maritime exposure and salt-laden winds, it is also very fast growing. Increases in height of between 1 and 2.5 metres per year have been recorded even in exposed positions, it makes an excellent shelterbelt tree[, , ].
The tree has been used in soil conservation projects[].
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[].

An extract of the bark is used as an ingredient in commercial cosmetic preparations as an antioxidant[].

Oleoresin is tapped from the trees and distilled to obtain turpentine and rosin[]. 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[].
Turpentine consists of an average of 20% of the oleo-resin[] and is separated by distillation[, ]. Turpentine has a wide range of uses including pine oil, terpene resins, flavours and fragrances, as a solvent for waxes etc, for making varnish, medicinal etc[, ].
Rosin is the substance left after turpentine is removed. This is used by violinists on their bows and also in making sealing wax, varnish, emulsifiers, synthetic resins, paper, inks, soap and glue etc[, ].
Pitch can also be obtained from the resin and is used for waterproofing, as a wood preservative etc.

The heartwood is pinkish brown; it is distinctly demarcated from the exceptionally wide band of creamy white sapwood, which constitutes the bulk of the commercial timber. The grain is often spiralled near the pith, but elsewhere usually straight; texture moderately fine and even; growth rings are up to 3cm wide; numerous resin canals are present; knots are common. The wood is light to medium weight; fairly soft; comprising mainly of sapwood, it is not durable, being susceptible to attacks by fungi and termites, and occasional damage by Anobium, pinhole and longhorn borers. The sapwood is not susceptible to Lyctus borers.. The wood air dries well. Wood to be used for joinery needs kiln drying for 2 - 3 days to remove stresses after air drying. It saws easily, but splitting may occur in thick logs; it works well with hand and machine tools, and careful planing gives a good surface; it takes nails well, but older and denser wood may split; holding properties for screws are good; it glues, paints and varnishes well; it is not suitable for steam bending. The wood is used for construction, joinery, furniture, veneer, plywood, packing cases, poles, posts, shuttering, particle board and fibreboard. It is also suitable for flooring, interior trim, toys, turnery, matches, railway sleepers, hardboard and wood-wool. It is widely used for paper making[].
The wood is used for fuel[]. The energy value of the wood is 20,470 kJ/kg[].

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[].