STARKVILLE, Miss.—Determining the stiffest piece of lumber is now easier with a new smartphone app created by scientists in Mississippi State University’s Forest and Wildlife Research Center.  Called “Smart Thumper,” the app uses soundwaves or vibrations to determine stiffness, a quality that relates to strength, for individual pieces of lumber.  Developer Dan Seale, professor in MSU’s Department of Sustainable Bioproducts, said it will help carpenters, contractors, architects, engineers, lumber mill personnel and consumers. He pointed out that it can be particularly beneficial for the do-it-yourself market. …“With this app, I can show you which lumber pieces are stiffer and therefore stronger,” Franca explained. “This can’t always be done through visual inspection. You need vibration or you need sound.” The app is available for download in the Apple Store.