Derek - I don't think that there was a Royal Navy in 1390.
The use of juvenile timbers rather than old growth has probably got more to do with being able to take advantage of the long established woodland management technique of coppice grown timber cultivation which requires the regular harvesting of timbers which are just fit for purpose with their removal at the earliest opportunity having the added benefit of reducing the complexity of conversion and wastage of excess amounts of wood.
An oak cruck framed building just up the road from me at Silchester has been dated to (circa) 1405 and it was established during the dendro process that all of the primary timbers in this frame had less than 40 growth rings each, with some of the annual ring widths reaching 5/8".
During a TFG executive visit to Cressing Temple in Essex in spring 1993, (following the fire at Windsor Castle) Cecil Hewett pointed out to the assembled group of carpenters that the rafters in the great barns dating from the early to mid 1200's exhibited only 25 growth rings at their feet and that these were hewn as a single piece from wall plate to arcade plate and again from the arcade plate to ridge. Later Oliver Rackham established that these rafters were all converted singly from trees of approx 45 - 50 years age with branch knot patterns indicating that the trees were all close grown in the woodland (coppice ?).
