Everyone needs a few earth tones in their look.  This Oxford buttondown in dark olive pairs really well with blue jeans.  With brown horn buttons and a soft buttondown collar.
 
Soft buttondown collar
Brown horn buttons
Slim fitting with a slightly higher armhole for a sleek look
Single chest pocket
Adjustable cuffs with two buttons and gauntlet buttons
Shaped hem will look great untucked
Shorter tail length to be worn untucked if you wish
No pleats for easy ironing and clean lines
100% cotton
Made in Canada
Fabric milled in Portugal
 
Model is 6', slim, and wearing a medium.