The city is collecting Christmas trees for recycling Jan. 7 through Jan. 18. Residents should leave their trees on the curb by 7 a.m. on their regular collection day during the two-week period, according to the Department of Public Works. All decorations and lights must be removed, and the trees cannot be in a bag. After Jan. 18, residents will be responsible for disposing of their trees, which will not be accepted as bulk waste. More information can be found at www.newtonma.gov/gov/dpw.