I would like to put a brick paver patio in my backyard, and I have
done the research regarding the amount of aggregate and sand that
needs to be placed under the pavers to keep them stable. I figure I
will need to dig about 6 - 8" into the ground and begin layering my
aggregate etc.

Trouble is, I have a rather large pine tree right against the side of
one of the edges of the patio, and am not sure how deep I can dig
before hitting the roots. My guess is about 4" before hitting them.

Can I dig down the shallow and still put the required amount of
aggregate - which will bring the patio 4" above grade. I can easily
put more soil around the edges to "smooth" out the difference to make
it look aesthetically pleasing. But I am not sure if this will
present issues with freezing during the winter.

Looking for some advice!

Thanks.