Monterey Pine or Radiata Pine (Pinus radiata) is found naturally in the coastal area around Monterey in California. There, it is under threat from Pine Pitch Canker (a fungal disease), which makes them liable to attack by bark beetles. Monterey pine is to be found growing in milder parts of the UK (where it grows faster than in its native habitat), and in coastal areas as it is resistant to salt spray.
The pine is extensively and intensively used in forestry, especially in countries like New Zealand (like the Kaingaroa Forest on the North Island). The monterey pine can be used for erosion control on steep slopes - as it has a widespread and fast growing root system
The growth form of the tree is conic at first, but as the tree ages it becomes dome shaped with heavily, twisted branches.
In California, the height is usually between 50 and 100 ft but it can grow much taller under optimal conditions. The bark is notably fissured (see image), grey in colour though it can assume a purple black hue with time .
The leaves / needles are bright green, and arranged in threes. They are quite long (3 to 6 inches) and slender. The cones are also quite big, sometimes described as ‘fist sized’ – they are brown, long and egg shaped with a prickle associated with each scale.
The cones are also described as serotinous – that is to say, they open up after a forest fire to release the seeds onto the forest floor. The cone provides protection from the heat of fire together with a mechanism for seed release. In some cones, this involves a resin that 'seals' the cone scales shut, but which 'melts' when heated. The 'ash bed' present after a fire means that there is an increase in the nutrients in soil and surface layers available to seeds and the process of germination.
Thanks to Dick White (woodlands.co.uk agent, Cornwall and West Devon) for photos