Is heap memory released after the termination of a thread?

[Vitali]

Hello,
in [1] is said that data defined in modules, if it's not shared, 
is copied for each thread. This means that new memory for this 
data is allocated every time when a new thread is started and 
when the thread terminates it is released [2].

But how about the memory created by this thread on the heap? Is 
it released, too, especialy when the garbage collector is turned 
off?

Thank you.

References
[1] 
http://www.informit.com/articles/article.aspx?p=1609144&seqNum=3
[2] http://dlang.org/module.html