A Cretaceous forest made of ancient pines. (Episode 3.10)
Ancient Pines were the predecessors to modern day pine trees. The Cretaceous forest that Abby Maitland and Connor Temple got stranded in was believed, by Connor, to be made up of ancient pines. The pair climbed them several times to avoid the Cretaceous predators. (Episode 3.10 and 4.1)