PLANT SCIENCE
'(<a href="http://www.j-archive.com/media/2010-11-17_DJ_15.jpg" target="_blank">Sarah of the Clue Crew presents the clue on a monitor.</a>)  Spruce needles are green all around, & in <a href="http://www.j-archive.com/media/2010-11-17_DJ_15a.jpg" target="_blank">cross section</a> you can see they're square; <a href="http://www.j-archive.com/media/2010-11-17_DJ_15b.jpg" target="_blank">flatter needles</a> with two light, lengthwise strips on the <a href="http://www.j-archive.com/media/2010-11-17_DJ_15c.jpg" target="_blank">underside</a> are from this 3-letter tree'
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