Mold is reactive in some senses but an equal mass of brain cells probably can be said to produce more abstract computation about self and other matters.

It may not ultimately be very useful to define consciousness so broadly as to include the tree whilst being willing to include mind's unalike our own.

It seems to me that it must necessarily include abstract computation inclusive of the self and volition separate from simple processes taking place in individual cells.

While it may be accurate to describe our own selves as the sum of our individual cells operations it is also possible to look at it top down as accurately.

I'm not sure that the tree grew towards the light or the mold towards moisture is as meaningful a concept as the monkey climbed the tree to eat the fruit and I don't think the distinction is the similarities to self.

I don't believe that the tree had within itself an organized center with a computed symbol for light or growth.

I also don't think it contains any ability to change the fixed computation represented by the system of it's cells or to arrive at different speculative computation of past or future.