A fallen Scots pine on the edge of the forest next to a clear cut area near Veberöd, Sweden. The tree has broken by high winds in a storm during the early spring. Volatile monoterpenes (primarily alpha-pinene, terpinolene and 3-carene)
emanate from resin wounds and attract pine shoot beetles, Tomicus piniperda, which feed in the phloem layer or the still-living tree which can offer
no further defense (by producing more resin).