Hmmm... people got e.coli from contaminated Christmas trees?!
(Looking at the German article... aha, "Sprossen" -- searching for "Sprossen" on Google Images -- oooh, bean sprouts!)
"Spruce" is a type of ёлка. And after checking Wikipedia I've learned that "sprouts" are ростки, but if you mean specifically "mung-bean sprouts" (the most popular and widely-sold kind) then it's ростки бобов мунг. Good to know!