Locations of birch (Betula celtiberica) and oak (Quercus robur) trees in a secondary wood in Urkiola Natural Park (Basque country, northern Spain). They are part of a more extensive dataset collected and analysed by Laskurain (2008). The coordinates of the trees are given in meters.
data(urkiola)An object of class "ppp" representing the point pattern of
tree locations. Entries include
Cartesian x-coordinate of tree in metres
Cartesian y-coordinate of tree in metres
factor indicating species of each tree
The levels of marks are birch and oak.
See ppp.object
for details of the format of a ppp object.
Laskurain, N. A. (2008) Dinámica espacio-temporal de un bosque secundario en el Parque Natural de Urkiola (Bizkaia). Tesis Doctoral. Universidad del País Vasco /Euskal Herriko Unibertsitatea.