Masting global distribution

Mast seeding occurs all over the globe with some countries having more masting species than others. Traditionally it has been thought of as prominent in northern hemisphere temperate forests, such as the oak (Quercus) forests of the eastern USA and conifer forests of the boreal north, but other famous examples are well known (such as south-east Asian Dipterocarp forests, bamboos in Asia and South America, and New Zealand snow tussocks). Global reviews have been carried out by Silvertown (1980), Kelly (1994), Herrera et al. (1998), Koenig & Knops (2000), and Kelly & Sork (2002). The latter study found 570 datasets of at least 6 years duration, but they were mainly from a few well-studied parts of the globe. For example in the USA, Finland and New Zealand there are large numbers of masting studies while in Asia, Africa and South America very few published masting studies were found (see map). Kelly & Sork (2002) discuss to what extent this reflects a lack of masting species, as opposed to a lack of published studies. They concluded that masting is likely to be concentrated in lower-productivity habitats (such as colder or drier sites), so the low number of tropical studies may not be completely an artifact of the density of scientists. This conclusion was supported by a comparison between Panama and Japan (Wright et al. 2005).

oak tree, acorns & squirrel
World map illustrating the global distribution of studies that have been performed on mast seeding species.