The Maine Forest Service is on the look out for very big trees.

The service is now taking nominations for the 2011/2012 Maine Register of Big Trees through Dec. 31.

The service has been compiling a list of the largest known specimens of various native and naturalized species since 1968. Four trees on the current register, including Yarmouth’s “Herbie” the New England Champion American elm, have died.

The candidates are measured by state foresters and given a score based on circumference, height and the crown spread.

Information on how to nominate a tree is available by contacting Jan Santerre, big tree coordinator, Maine Forest Service, 22 State House Station, Augusta ME 04333 or at 1-800-367-0223 or online at  www.projectcanopy.maine.gov