15% Off Pressure Treated Lumber + New Flyer!Posted on May 18, 2016 by Northumberland Coop • 6 CommentsGet 15% off pressure treated lumber for 3 days only! Thursday May 19 to Saturday May 21. Plus check out great deals in our new flyer with prices in effect until May 29. Lawn, garden, tools and more! Click the flyer below to browse.