The Collaborative International Dictionary of English v.0.48:

Treen \Treen\, a. [AS. tre['o]wen.]
   1. Made of wood; wooden. [Obs.] " Treen cups." --Camden.
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   2. Relating to, or drawn from, trees. [Obs.] --Spenser.
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            Treen liquors, especially that of the date.
                                                  --Evelyn.
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The Collaborative International Dictionary of English v.0.48:

Treen \Treen\, obs.
   pl. of Tree. " The shady treen." --Fairfax.
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