For more than a century, botanists have known trees add one ring each year and that the rings preserve details about tree growth.
(the rings; preserve; details about tree growth) (botanists; have known; trees add one ring each year and that the rings preserve details about tree growth; T:For more than a century) Context(botanists have known,List([25, 45))):(trees; add; one ring; T:each year)
botanists have known,List([25, 45))
the rings botanists trees
preserve have known add
details about tree growth
trees add one ring each year and that the rings preserve details about tree growth T:For more than a century
one ring T:each year