@article {337,
	title = {Interactions of factors affecting seedling recruitment of Blue oak (Quercus douglasii) in California},
	journal = {Ecology},
	volume = {70},
	number = {2},
	year = {1989},
	note = {this paper is the origin of the northness index as an estimate of relative solar insolation derived from slope and aspect (azimuth from north)},
	pages = {389-404},
	keywords = {acorn blue oak cattle exclosures gophers interaction mice predation seedling woodland classification and regression tree (CART) hierarchical cluster analysis stepwise logistic regression American Canyon Agua Escondido San Luis Obispo County northness inde},
	author = {Borchert, M. I. and Davis, F. W. and Michaelsen, J. and Oyler, L. D.}
}
