Primary succession to forest on some island and continental Pacific volcanoes

We have directly measured or spatially inferred primary forest succession following destruction by volcanic eruptions in a wide range of Pacific locations. Settings vary from extremely isolated islands (Hawaii) to moderately isolated islands with continental heritage (New Zealand), to Pacific Rim continental (North America).  A continuum of successional pattern is apparent.  “Direct” succession is characteristic of sites with a limited flora, excessive isolation or extreme habitat conditions (including intermittent continuing disturbance).  “Normal” succession is characteristic of sites where a larger species pool is available, disturbance return times greatly exceed the life span of late successional species, or habitat conditions are within tolerance ranges of a suite of tree species.  Lack of certain functional types in the species pool or their failure to invade can delay development of more complex “climax” forests.  Alien plants have locally enhanced some early or mid succession functional types but have not prevented later dominance by native trees.  Alien animals, however, have locally altered composition and abundance of mid and late successional native trees.  New Zealand overall has characteristics intermediate to true island syndrome forests or continental forests.