Ok, I'm a bit pressed for time so hopefully this will come out right. Stay with me on this one:

I was cutting the grass, yesterday, and came across this strange series of thoughts.
Consciousness – How do we gauge what is conscious and what isn’t?

Is a tree conscious? Is the grass? The flowers? Are amoebas conscious? Is bacteria? Algae? Jellyfish have no brains. Are they conscious? Is the earth, as a whole, a sentient being?

On the surface, these may seem like your average, everyday, “mystical zealot” banter, and the concept is debated all the time, but I mean, really think about it. Most things that we collectively agree are conscious have hearts, organs, neural networks, or any combination of the like. Most of them are animate, not only in the sense that they grow and die, but in that they have motor-systems for powering body parts, whether it be arms or legs, or a digestive tract.
Most importantly, they have a way of expressing this consciousness. Most of them respond to stimuli on a readily observable level, most tellingly; the ability to communicate in a way that proves they are responding to the stimuli in question, as it happens.
However, looking further, we have to ask ourselves…is a living thing, or a group of living things, without any sort of way of communication, conscious? If not, why not? If so, how so? How do we go about telling the difference?
There was once an experiment done (allegedly) where a scientist removed up to 90% of a salamander’s brain without causing any sort of observable difference in the salamander’s behavior. Even after that, it was only a small difference. Shortly after removing more, the salamander finally died. There is a college student somewhere (if I have to find the article, I will) that has nearly 90% of his gray matter missing and still has a very high IQ and functions just as well, if not better, than any “full capacity human.” Many scientists even speculate that memories are not localized anywhere in the brain, but (assuming they are in the brain at all) that they might be somehow dispersed about the brain as a whole, behaving like a hologram in that every section and cell contains a whole of an organisms memory bank, which cannot be ruptured by removing large portions of the brain itself.
What if the brain has no connection to consciousness? What if the brain is simply the motor for running the body that we inhabit? What if we were stationary organisms, though arguably “alive” (such as trees, grass, etc)? Would we still need a brain to be considered conscious? Would we still have some sort of sentience, albeit on a completely different scale than a 5-sense human?
Would the concept of still being “me” apply, even though there was no way to express it? Medically, we call this condition being a vegetable. (which may be a more fitting metaphor than some of us realize.) It is very common. There is still definitely a sense of being, a sense of consciousness, at least so far as we know. People in comas have been said to dream. Is the little bit of neural activity observable a direct connection to that dreaming? To any sort of sentience? Or is it simply a byproduct of the body still working to “function” to breath (which may be more of a means for fueling the body/machine than for “life” in terms of sentience.)

If this is true, would it not be feasible that the blades of grass and the trees which grow, function, operate, feed, thrive, are actually sentient beings with no way of communicating their sentience?

Thoughts?