Ask Mr. Smarty Plants

It is not too likely that you will be able to find information for specific fruiting times such as the exact month for all native trees and shrubs from the Pacific Northwest.  In general, identification guides may show flowering times (and these can span several months), but I haven't seen a field guide that states the fruiting period in any of the identification books that I have (and I have more than two dozen for the Pacific Northwest).  As you say, it will be after they bloom but no indication of how long after they bloom.  Additionally, it is difficult to name specific fruiting periods since weather patterns are not the same every year and that affects when the plants bloom and produce fruit.   The latitude and the elevation also affects blooming and fruiting.

The United States Department of Agriculture (USDA) may be your best source for finding fruiting times.  You can find information for some plants by looking up the particular species on the Fire Effects Information System (FEIS) database of the USDA Forest Service.  For instance, you can find a table showing the earliest, average and latest dates for leaf, flower, and fruit development for Arctostaphylos uva-ursi (Kinnikinnick) under the heading SEASONAL DEVELOPMENT in the section BOTANICAL AND ECOLOGICAL CHARACTERISTICS on the species' page.  For Rubus idaeus (American red raspberry) there is also a table under SEASONAL DEVELOPMENT for flowering and fruiting dates under BOTANICAL AND ECOLOGICAL CHARACTERISTICS on its page.   The locations for dates are shown for both these species, but they are not necessarily dates for the Pacific Northwest.  The USDA Plants Database has information for some plants under the heading of "Characteristics".  For Rubus idaeus (American red raspberry) in the "Reproduction" section under the "Characteristics" heading, it states the Bloom Period is Spring, the Fruit/Seed Period Begin is Summer and Fruit/Seed Period End is Summer.   The information for all of the native trees and shrubs of the Pacific Northwest may not be on these two sites but you can find some of them by searching by their botanical name on the sites.

If you are a wild plant forager and are looking for fruiting dates for that reason, there are a few foraging books that focus on the Pacific Northwest and other more general foraging books that could be useful.  Here are four examples:

North West Foraging (Revised edition, 2011) by Doug Benoliel has a chapter "Seasonal Edibles" that gives information about the season when various plants and parts of plants are available.  In the beginning of the chapter he explains that the time of the seasons depends on the elevation. Spring, for instance, could mean April through June at sea level and only July at higher elevations. 

Pacific Northwest Foraging: 120 Wild and Flavorful Edibles from Alaska Blueberries to Wild Hazelnuts by Douglas Deur, publication date June, 2014, will have information about what to look for and when and where to look.

The Deerholme Foraging Book: Wild Foods and Recipes from the Pacific Northwest by Bill Jones, publication date April 2014.

The Forager's Harvest: A Guide to Identifying, Harvesting and Preparing Edible Wild Plants by Samuel Thayer (2006) has a Harvest Calendar in it.

There are also foraging sites on the internet:

• Year-Round Northwest Foraging Calendar from The Oregonian
• Pacific Northwest Wild Food, Foraging, Mushrooms, Ethnobotany, Fishing – Calendar from Fresh-Picked Seattle
• Pacific Northwest Wild Edibles and Foraging on Facebook

There are more that you can find by googling "Foraging Northwest".