The species' genomic change is about 2,000 times slower than in humans, making it a "molecular fossil", a team of US researchers said.
The new information has affected our understanding of flowering plants' evolution, they added.
The findings have been published in the open access journal BMC Biology.
The team from the universities of Indiana and Arkansas sequenced the mitochondrial genome of the species (Liriodendron tulipifera), only to discover it had one of the slowest silent mutation rates (a process that does not affect gene function).
They added that the sequencing showed that many of the genes that had been lost during 200 million years of flowering plants' (angiosperms) evolution had been preserved.
"Based on this, it appears that the genome has been more-or-less frozen in time for millions and millions of years," explained co-author Prof Jeffrey Palmer.
Continue reading Tulip tree's genome is 'molecular fossil'