Living organisms are constantly incorporating this C-14 into their bodies along with other carbon isotopes.
When the organisms die, they stop incorporating new C-14, and the old C-14 starts to decay back into N-14 by emitting beta particles.
Of course, species of tree tend to produce two or more growth rings per year.
But other species produce scarcely any extra rings.
When dating wood there is no such problem because wood gets its carbon straight from the air, complete with a full dose of C-14.
Other species of trees corroborate the work that Ferguson did with bristlecone pines.ICR creationists claim that this discredits C-14 dating. Answer: It does discredit the C-14 dating of freshwater mussels, but that's about all.Kieth and Anderson show considerable evidence that the mussels acquired much of their carbon from the limestone of the waters they lived in and from some very old humus as well.However, the amount of C-14 has not been rising steadily as Cook maintains; instead, it has fluctuated up and down over the past ten thousand years. From radiocarbon dates taken from bristlecone pines.There are two ways of dating wood from bristlecone pines: one can count rings or one can radiocarbon-date the wood.
When experts compare the tree-ring dates with the C-14 dates, they find that radiocarbon ages before 1000 BC are really too young—not too old as Cook maintains.