Reddit reviews Flora of the Pacific Northwest: An Illustrated Manual
We found 4 Reddit comments about Flora of the Pacific Northwest: An Illustrated Manual. Here are the top ones, ranked by their Reddit score.
It is Arabidopsis. Anyone who farms in the western us should get this book, it is a very helpful reference.
http://www.amazon.com/Weeds-West-Tom-D-Whitson/dp/0756711827/ref=pd_sim_b_4/181-9259276-8260968?ie=UTF8&refRID=1T8PXM4H80XWMSET9FQY
Or if you really want to be nerdy you can use the same book I had to use in school. http://www.amazon.com/Flora-Pacific-Northwest-Illustrated-Manual/dp/0295952733
EDIT: Grammar
i used this for a botany class in college. It's a technical key of (obviously) flora of the pacific northwest region of the USA. The illustrations are fantastic but they are not the main focus.
https://www.amazon.com/Flora-Pacific-Northwest-Illustrated-Manual/dp/0295952733/ref=sr_1_1?ie=UTF8&qid=1482321487&sr=8-1&keywords=flora+of+the+pacific+northwest
The Flora of the Pacific Northwest is the book you want. It has full keys. Picture guides specifically related to the northwest (like this and this) can be used to supplement this, but FPN is the best authority for most of that region.
"Wildflowers of North America" and Newcomb's Guide and things like that are not going to help you at all. They mostly cover Eastern species and there is rather little botanical overlap between there and the Pacific Northwest.
As keys are very technical, it would help to know what you are looking for. Animals or plants and what region?
For instance, the key I use in my job is Flora of the Pacific Northwest and only covers NW plants. Even more specific is Field Guide to the Sedges of the Northwest. As you can see, they get more specific and technical depending on your focus. Plants in the NW are my specialty, animal keys are a bit harder to come by. For animals you generally only find field guides.
There are no good apps that have dichotomous keys that I know of, for the reasons I stated earlier.