Old Growth vs. Second Growth
Is there a difference between old growth redwood and more recently planted “second growth” redwood. YES!! It’s apples and oranges, Lexus and Yugo.
Second growth redwood is grown as a crop by the large timber companies and is harvested on a 20-30 year cycle. Sure, it’s called redwood but a large portion of it is white. It is soft and brittle lumber and lacks the extractives that help old growth lumber last a long long time. Second growth is fine for fence boards and garden projects with a typically short life span. Decking, siding, fascia and anything else out in the weather-not so much. For these applications you specify old growth redwood if you want it to last for decades.
It’s all about the growth rings. There are actually 2 growth rings in a one year growing cycle. The earlywood is the light colored ring and the latewood is the hard dark colored ring. Note that the proportion of earlywood to latewood in young growth is much more the soft earlywood. In old growth it’s usually more evenly divided. Much more hard strong late wood as a percentage. The softer earlywood is the first to get soft and weather away.