There are two sets of study materials you will need to purchase as study guides to prepare for the CPH Exam.
A) Sustainable Gardening Handbook ordered from OSU
EM8742: Sustainable Gardening: The Oregon-Washington Master Gardener Handbook
Order on-line at http://extension.oregonstate.edu/catalog/abstract.php?seriesno=EM+8742 the search field type in EM8742
Oregon State University
Cost: $30.00 plus tax and shipping
B) WSNLA Provided Study Materials.
CPH Plant Identification List
Naming of Plants