Trees growing on rocks, do Lichens help them?

I am always curious about such things. Always wondered about the existence and nature.

Yes trees, plants and Lichen grown on a bare rock and I have taken photos from multiple places in Karnataka like Siddarabetta, Chitradurga, Devarayana durga. I assume there is a relation between these Lichen and these trees and plants growing on rock. Lichen is pronounced as "lyken" and they grow on rocks.

See below the photos, variety of them are shown in different areas. As you can imagine, Bird's poop on the rocks which contains the seed initiate this whole process.

These trees and plants break the rocks apart with their roots and penetrate through them. We need bigger and sharper tools to break the rocks. But they need just their roots. How amazing !

During school days, we studied about the plants, they need water, air, sunlight and soil for the growth.
But then how do these trees get water and soil from rocks?  A big question striked me as well. Atleast I could imagine, they can get water substance from the air (might be in early mornings), Or they can penetrate and go deeper down the rocks to find water. In Siddarabetta caves I have seen that the vines go deeper through the rocks to find water.

But how about the soil they need. They dont get it on rocks right?  These Lichens gain the nutrients from air and atmosphere. Though they look dead in dry season, they seem to grow back when moisten returns in air. When I searched about the fungus which is the only term I could recollect, before searching in google.
I got the link about Lichen in Wiki. http://en.wikipedia.org/wiki/Lichen

It says these Lichens do contribute to weathering of rocks which gradually turn into soil.

Now I wonder if this Lichen and those trees and plants are helping each other ? I don't know really.
If you know please share your comments below. Anyway it is amazing to see such wonders....

Shared my photos for your curiosity as well.... Enjoy....

Note: These are the photos from Siddarabetta, Chitradurga and Devarayana durga.

this is in Siddarabetta

Colorful Lichens growing on the bare rocks, in Devarayana durga

This is in Siddarabetta, full grown tree on bare rock

Lichens growing on the rock, notice the change in color

Roots going deeper through the gaps in rocks in search of water.... in Siddarabetta

Such a big root, looks multiple of them joined together in search of water? In Siddarabetta again...

Full grown tree on the bare rock. This is in Chitradurga

In Chitradurga

Seedling and Lichens - in Shivagange Hills near Tumkur

Seedling and Lichens on the bare rock in Shivagange Hills near Tumkur

from a distance...... in Shivagange Hills near Tumkur

Yet another full grown tree on bare rock

how old are you dear? all the best ... in Devarayana Durga

Seedling .... in Devarayana Durga

Do you see the grass on the centre of the photo on the rock? in Devarayana durga

Colorful lichens in Devarayana durga

Another variety of Lichen in Devarayana Durga

One more variety i suppose... in Devarayana Durga

Full grown tree on bare rock again... in Devarayana Durga

another tree on bare rock, but the roots touched the ground... in Devarayana durga

Growth of Lichens on rock in Devarayana durga

Another view of growth of Lichens in Devarayana Durga