Call my Bluff Traditional Cache

"Beloved, gaze in thine own heart, 
The holy tree is growing there; 
From joy the holy branches start, 
And all the trembling flowers they bear. 
The changing colours of its fruit 
Have dowered the stars with metry light; 
The surety of its hidden ROOT 
Has planted quiet in the night; 
The shaking of its leafy head 
Has given the waves their melody, 
And made my lips and music wed, 
Murmuring a wizard song for thee."
-  William Butler Yeats, The Two Trees