Ask Mr. Smarty Plants

Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler climates. Its scientific name is Solanum lycopersicum, which means it is in the nightshade family. You might be interested in this article from Science Daily on nightshade plants.

However, while the tomato is not one of the deadly members of this family, it also is not native to North America. The Lady Bird Johnson Wildflower Center, home of Mr. Smarty Plants, is dedicated to the growth, propagation and protection of plants native not only to  North America, but to the area in which that plant grows natively.

You can do a search on "tomato pests and diseases" and get a number of sites, with pictures and solutions, to answer your question.

Your best source of information, since this is a food grown to eat, is probably the Washington State University Extension Office for Spokane County. There is contact information on that website, and they are bound to know more about tomatoes and growing them in Washington than we do.