In 1945, Maine State Senator Ruth T. Clough, of Penobscot, presented a Resolve to the Maine State Legislature that proposed that the white pine be designated the state's official tree. What other tree would better serve The Pine Tree State?
In Maine, Resolves are defined as "Laws having a temporary or limited purpose that do not amend the general public laws (e.g., a resolve to allow an individual to sue the State)." 
Legislative Document No. 381, as approved by the legislature, was recorded on page number 848 of ACTS AND RESOLVES AS PASSED BY THE Ninety-first and Ninety-second Legislatures OF THE STATE OF MAINE.
RESOLVE, Designating the White Pine Tree as the State Official Tree.
White pine tree, official state tree. Resolved: That the white pine tree be, and hereby is, designated the official tree of the State of Maine.
Effective July 21, 1945
In 1959, fourteen years after acting by Resolve, the Maine Legislature again addressed the status of the white pine as official tree of the State of Maine.
In Legislative Document No. 1171, "AN ACT to Correct Errors and Inconsistencies in the Public Laws," the status of the white pine was upgraded in a sense, elevated to a position in the Maine Revised Statutes by the Ninety-ninth Legislature.
In addition to the state tree, Legislative Document No. 1171 granted promotions to the state floral emblem, adopted by Resolve in 1895, the state bird adopted by Resolve in 1927 and the state song, adopted by Resolve in 1937.
The following is an excerpt pertaining to the official tree from Legislative Document No. 1171 presented by Senator Weeks of Cumberland. The entire document is eighteen pages long. The excerpt, that includes reference to the "promoted" state symbols mentioned above, is comprised of a little more than a page.
L. D. 1171
STATE OF MAINE
IN THE YEAR OF OUR LORD NINETEEN HUNDRED FIFTY-NINE
AN ACT to Correct Errors and Inconsitencies in the Public Laws.
Be it enacted by the People of the State of Maine, as follows:
Sec. 1. R.T., c. 1, §§ 24-B - 24-C, additional. Chapter 1 of the Revised Statutes is amended by adding thereto 2 new section to be numbered 24-B and 24-C, as follows:
'State Seal, Motto, Flag and Other Emblems.
Sec. 24-B. State seal. The seal of the State shall be a shield, argent, charged with a pine tree (Americana, wuinis ex uno folliculo setis) with a moose deer (cervus alces), at the foot of it, recumbent; supporters: on dexter side, a husbandman, resting on a scythe; on sinister side, a seaman, resting on an anchor.
In the foreground, representing sea and land, and under the shield, shall be the name of the State in large Roman capitals, to wit:
The whole shall be surrounded by a crest, the North Star. The motto, in small Roman capitals, shall be in a label interposed between the shield and crest, viz:--DIRIGO. (Resolves, 1820, c. 4.)'
Sec. 2. R. S. , c. 1, §§ 26-A - 26-D, additional. Chapter 1 of the Revised Statutes is amended by adding thereto 4 new sections, to be number 26-A to 26-D, as follows:
'Sec. 26-A. State tree. The official tree of the State shall be the white pine tree. (Resolves, 1945, c. 8.)
Sec. 26-B. State bird. The state bird shall be the chickadee. (Resolves, 1927, c. III.)
Sec. 26-C. State song. The official song of the State shall be the song entitled "State of Maine Song" composed by Roger Vinton Snow. (Resolves, 1937, c. 39.)
Sec. 26-D. State flower. The floral emblem for the State, in the national garland of flowers, shall be the pine cone and tassel. (Resolves, 1895, c. 3.)'
As yet, we have no definitive information regarding the detailed movement of the measure through the legislature. We also do not when or if the legislation was signed by the governor. Interestingly, the governor's office was held by a couple of different people in 1959.
Though we don't know the final approval date, we do know that the effective date of this approved bill was September 12, 1959.
No scientific designation is provided in the text approved by the Maine Legislature, an assumption is made that the intended species is Pinus strobus, the eastern white pine.
Initially adopted by legislative resolve in 1945, the white pine tree was later elevated in stature in 1959. The following information, created by Legislative Document No. 1171 in 1959 was excerpted from the Maine Revised Statutes, Title 1, Chapter 9, Subchapter 1, Section 208.
Title 1: GENERAL PROVISIONS
Chapter 9: SEAL, MOTTO, EMBLEMS AND FLAGS
Subchapter 1: GENERAL PROVISIONS
§208. State tree.
The official tree of the State shall be the white pine tree.
 Acts and Resolves As Passed by the Ninety-first and Ninety-second Legislatures of the State of Maine. Page 845. 1945.
Maine State Legislature, Maine Revised Statutes, , September 26, 2008.
Shearer, Benjamin F. and Barbara S. State Names, Seals, Flags and Symbols: A Historical Guide Third Edition, Revised and Expanded. Westport, Conn: Greenwood Press, 3 Sub edition, 2001.
Celebrating Maine?s State Tree: Eastern White Pine: Forests for Maine's Future.
Eastern White Pine (Pinus strobus): Maine Department of Agriculture, Conservation and Forestry.
Eastern white pine (Pinus strobus) state tree of MAINE, MICHIGAN: The United States National Arboretum, Washington, DC.
Pinus strobus (Eastern White Pine, Weymouth Pine): American Conifer Society.
eastern white pine (Pinaceae Pinus strobus L.): Virginia Tech Department of Forest Resources and Environmental Conservation.
Pinus strobus Linnaeus 1753, p. 1001: The Gymnosperm Database.
Pinus strobus (white pine tree): USDA, NRCS. 2016. The PLANTS Database (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
Pinus strobus L.: Integrated Taxonomic Information System (ITIS).
Pinus strobus: Search for images of Pinus strobus with Google.
State trees: Complete list of official state trees from NETSTATE.COM.
More symbols & emblems: Complete list of official Maine state symbols from NETSTATE.COM.
Maine Trees & Wildflowers, by James Kavanagh. Folding pamphlet. Publisher: Waterford Press; 1st edition (May 1, 2008)
The state tree - the eastern white pine - is one of thousands of species of plants growing in the diverse ecosystems found throughout the Pine Tree State. This beautifully illustrated guide highlights over 140 familiar and unique species of trees, shrubs and wildflowers. It also includes an ecoregion map featuring prominent botanical sanctuaries that any nature enthusiast would love to explore. Laminated for durability, this lightweight, pocket-sized folding guide is an excellent source of portable information and ideal for field use by visitors and residents alike.
Bark: A Field Guide to Trees of the Northeast, by Michael Wojtech. 280 pages. Publisher: University Press of New England (April 12, 2011)
Many people know how to identify trees by their leaves, but what about when those leaves have fallen or are out of reach? With detailed information and illustrations covering each phase of a tree?s lifecycle, this indispensable guidebook explains how to identify trees by their bark alone.
Chapters on the structure and ecology of tree bark, descriptions of bark appearance, an easy-to-use identification key, and supplemental information on non-bark characteristics?all enhanced by over 450 photographs, illustrations, and maps?will show you how to distinguish the textures, shapes, and colors of bark to recognize various tree species, and also understand why these traits evolved.
Whether you?re a professional naturalist or a parent leading a family hike, Bark: A Field Guide to Trees of the Northeast is your essential guide to the region?s 67 native and naturalized tree species.
National Audubon Society Field Guide to Trees: Eastern Region, 714 pages. Publisher: Alfred A. Knopf; Chanticleer Press Ed edition (May 12, 1980)
Tree peepers everywhere will enjoy this guide, to trees generally found in states east of the Rocky Mountains, which explore the incredible environment of our country?s forests-including seasonal features, habitat, range, and lore. Nearly 700 species of trees are detailed in photographs of leaf shape, bark, flowers, fruit, and fall leaves ? all can be quickly accessed making this the ideal field guide for any time of year.
Identifying Trees: An All-Season Guide to Eastern North America, by Michael D. Williams. 416 pages. Publisher: Stackpole Books; 1st edition (March 22, 2007)
Identify trees in any season, not just when they are in full leaf. This field-tested guide features color photos showing bark; branching patterns; fruits, flowers, or nuts; and overall appearance; as well as leaf color and shape--all chosen specifically to illustrate trees in spring, summer, winter, and fall. Accompanying text describes common locations and identifying characteristics. Created for in-the-field or at-home use, this guide includes an easy-to-use key that will help you put a name to any tree by flipping only a few pages. Covers every common tree in eastern North America.
America's Famous and Historic Trees: From George Washington's Tulip Poplar to Elvis Presley's Pin Oak by Jeffrey G. Meyer. 130 pages. Houghton Mifflin Harcourt; First Edition (April 20, 2001)
America's Famous and Historic Trees tells the stories of various trees that Meyer and his cohorts rescued or propagated: oftentimes, when trees were going to be cut down, he and his workers headed off the bulldozers, rescuing the tree with their massive tree hoe. Other trees--like the Indian Marker Pecan in southeast Dallas--were propagated before they died.
Trees : National Champions by Barbara Bosworth. 144 pages. The MIT Press; First Edition (August 19, 2005)
Bosworth captures the ineffable grace and dignity of trees with clarity and directness: the green ash that shades a Midwestern crossroads, the common pear that blooms in a Washington field, and the Florida strangler fig with its mass of entwining aerial roots. Her black and white photographs, panoramic views taken with an 8 x 10 camera, show the immensity of the largest species and the hidden triumphs of the smallest
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