Short, but interesting. There was something about your wording that seemed very meticulous to me, and I liked your comparisons and such. Although the "two worlds" thing is quite a cliche (hard to avoid in romance, I know) there's potential for making this unique. Keep on writing, and message me when more of this is finished. I'm not a fan of romance really, but I'm curious...keep writing.
Reading is one form of escape. Running for your life is another. ~Lemony Snicket
First of all, a nitpick! Weeds convert carbon dioxide to oxygen as well! In fact, most of the oxygen produced on this Earth is by grass... which is what category your dandelion seed would grow into! So that doesn't quiet work.
Also, what do you mean by love existing between an old oak and a dandelion seed? How would love even come about? As this is a story, I expect this relationship to be developed, as peculiar as that might sound!
Also, the message is a bit weird. Right now, it sounds like a Harold and Maude sort of thing going on... a bit weird, if you know what I mean!
Ubi caritas est vera, Deus ibi est.
"The mark of your ignorance is the depth of your belief in injustice and tragedy. What the caterpillar calls the end of the world, the Master calls the butterfly." ~ Richard Bach
