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Pinus radiata
Conservation status
Conservation Dependent (IUCN 2.3)
Scientific classification
Kingdom:	Plantae
Division:	Pinophyta
Class:	Pinopsida
Order:	Pinales
Family:	Pinaceae
Subfamily:	Pinoideae
Genus:	Pinus
Subgenus:	(Pinus)
Species:	P. radiata
Binomial name
Pinus radiata D.Don

Pinus radiata (family Pinaceae) is known in English as Monterey Pine or the Insignis Pine^[1] in some parts of the world (mainly in the USA, Canada and the British Isles), and Radiata Pine in others (primarily Australia and New Zealand).

It is a species of pine native to coastal California in three very limited areas in Santa Cruz, Monterey and San Luis Obispo Counties, and (as the variety Pinus radiata var. binata, Guadalupe Pine) on Guadalupe Island and (possibly separable as var./ssp. cedrosensis) Cedros Island off the west coast of Baja California, Mexico. It is also extensively cultivated in many other warm temperate parts of the world.

P. radiata grows to between 15-30 m in height in the wild, but up to 60 m in cultivation in optimum conditions, with upward pointing branches and a rounded top. The leaves ('needles') are bright green, in clusters of three (two in var. binata), slender, 8-15 cm long and with a blunt tip. The cones are 7-17 cm long, brown, ovoid (egg-shaped), and usually set asymmetrically on a branch, attached at an oblique angle. The bark is fissured and dark grey to brown.

It is closely related to Bishop Pine and Knobcone Pine, hybridizing readily with both species; it is distinguished from the former by needles in threes (not pairs), and from both by the cones not having a sharp spine on the scales.

[edit] Ecology and status

The forests in which Monterey Pine grows are associated with other characteristic flora and fauna of note. The only two forests in which Cupressus macrocarpa naturally occurs are located in coastal Monterey County, where P. radiata is a co-dominant overstory species.^[2] Furthermore, one of the pine forests in Monterey, California was the discovery site for Hickman's potentilla, an endangered species. Piperia yadonii, a rare species of orchid is endemic to the same pine forest adjacent to Pebble Beach. Nearby in a remnant pine forest of Pacific Grove, is a prime wintering habitat of the Monarch butterfly.^[3] .

In the wild, the Monterey Pine proper is seriously threatened in California by an introduced fungal disease, Pine Pitch Canker, caused by Fusarium circinatum.

On Guadalupe Island, var. binata is critically endangered. Most of the population was destroyed as tens of thousands of feral goats ate each and every seedling that germinated from the mid-19th century until just a few years ago. The older trees gradually died off until by 2001-02 the population stood at only one hundred. With a program to remove the goats essentially complete by 2005, hundreds of young Guadalupe Pines have started to grow up in habitat fenced after 2001, the first significant new growth in about 150 years. Possible accidental introduction of Pine Pitch Canker is considered the biggest threat at present to the survival of the Guadalupe Island pine population.^[4]

[edit] Cultivation and uses

In NZ scientists,initially from Norway, have selectively bred the tree so that it is barely recogonizable from the short twisted variety found in California .By selecting pollen from plus trees which showed ideal features of straight trunk,height,lack of low branches and greeness a much superior tree was produced.Since the 1980s an increasing proportion of seedlings have been prodecrd in Rotorua at the Forest Research Institute(FRI), using secret tissue culture methods, that produce endless examples of the parent tree .These are labelled GF(growth factor) seedling and are numbered from 1(earliest) to 30+.These trees are more expensive to purchase as seedlings but are far superior to earlier variaties.Some plantations are intensively managed with use of fertilizer to speed growth,optimised planting patterns and a triple pruning regime to produce tall, straight, very fast growing wood.Trees produced in this way reach a useful commercial size in 20 years or less-half the time of 30 rears ago.In the 1990s research showed that rapid growing young trees produced wood that was lighter, but weaker, so regulations were passed in NZ that trees younger than 18 years could not be used in house construction.Currently very high grade, clear(knot free) Pinus Radiata is widely available throughout NZ at very low prices.Most houses in NZ have been built of treated radiata timber since the 1960s.In its natural state the wood rots very rapidly if exposed to water.A fallen tree will rot completly in 2-3 years.Treatment is either by dipping in a chemcal solution(dyed red in NZ)or more commonly by drying in a large oven to reach a moisture content of 12% and then injecting chemicals under high pressue.This is called tanalizing in NZ.Tanalized wood is dyed green.Various degrees of pressure treatment are common to match uses:

H1 interior wood H2 wood exposed to slight moisture for a short time H3 weatherboards etc-timber that is exposed to rain but not in ground contact. H4 Timber in ground contact(retaining walls) H5 timber in the ground eg posts and poles

In the 1990s experiments with carefully dried ,but untreated wood ,were tried in NZ for interior house use, in response to a demand for chemical free wood by some consumers.This was known as Laser wood.The result was a disaster for the NZ housing indutry as it resulted in thousands of leaky homes that rotted from the inside.New building regulations have frevented the inappropriate use of Laser wood.Tanalized wood should never be burnt in a fire as the poisonous chemicals are released.Untreated pine is commonly used as fire wood in NZ and produces a lot of heat but burns away quickly. Since the 1980s small boat designers in NZ have produced designs for using the cheap,readily available pine either as plywood or longwood clears.Tanalized pine does not glue well so most designer builders cover the unteated wood with saturated epoxy resin.Quality Pinus Radiata is about 15% heavier than Western Red cedar but about 15% lighter than the various imported woods such as Sapele.Pinus radiata plywood is usually glued with waterproof resorcinal glue .The ply is commonly used in construction for a bracing material and flooring or for temporary concrete forms.H3 pine is commonly used for decking.

Australia also has large Radiata Pine plantations (though they are less than 1% of the total forested area); so much so that many Australians are concerned by the resulting loss of native wildlife habitat. A few native animals, however, thrive on P. radiata, notably the Yellow-tailed Black Cockatoo which, although deprived of much of its natural diet by massive habitat alteration through clearing for agriculture, feeds on P. radiata seeds. P. radiata has also been introduced to the Valdivian temperate rain forests of southern Chile, where vast plantations have been planted for timber, again displacing the native forests.

In areas such as New Zealand this tree has become naturalized, and is considered an invasive species (termed a wilding conifer) where it has escaped from plantations.

Detail of bark

Needles and spikes

Pine cone on forest floor

Monterey Pine plantation, Australia

[edit] Footnotes

[edit] References

Wikimedia Commons has media related to: Pinus radiata

• Conifer Specialist Group (1998). Pinus radiata. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006.
• Hogan, C. Michael & Frankis, Michael P. (2009): Monterey Cypress: Cupressus macrocarpa. GlobalTwitcher.com ed. N. Stromberg
• Junak, S.; Keitt, B.; Tershy, B.; Croll, D. & Sánchez, J.A. (2003): Recent conservation efforts and current status of the flora of Guadalupe Island, Baja California, Mexico. Presentation at Taller sobre la Restauración y Conservación de Isla Guadalupe ["Workshop on restoration and conservation of Guadalupe Island"]. Instituto Nacional de Ecología, November 13-14, 2003. HTML abstract
• León de la Luz, José Luis; Rebman, Jon P. & Oberbauer, Thomas (2003): On the urgency of conservation on Guadalupe Island, Mexico: is it a lost paradise? Biodiversity and Conservation 12(5): 1073–1082. doi:10.1023/A:1022854211166 (HTML abstract)