I find that most Japanese styles of poetry are difficult to master.
'Lumbering tree trunks
Hold masses of vivid greens
Providing natural shade'
From this we get a really big description, and from only a small amount of words, that's a great truimph. 'Lumbering' was a fantastic choice. You set the reader up for the contrast or contradiction in imagery in the second.
Destroying vast areas
Of this stunning wonderland'
That one word sits on it's own, and it's powerful like that. I maybe would have liked it if you'd related or linked the last line to the first stanza/line so the reader can familiarise with the imagery, but that's just minor. This was an excellently penned Sedoka.
With this poem you not only show how talented you are (Japanese formats are very hard to master!) but you also show commitment to the world around you. Indeed the rate at which our 'lungs"are being destroyed should have our fullest attention. If trees were to dissapear completely, we would too because they provide our oxygen!
Bravo, Ozzie girl:) You are a true gem, in so many ways:)