Lower quality trees that will only produce sawlogs as they mature actually show a similar  value growth increase.  You start with a smaller investment due to the lesser value per tree, but that initial investment will still bring very good returns to the forest owner who manages their forest wisely.  Sawlog value growth can bring up to 20%/year return today.  All timber is growing in value quickly due to stumpage price trends.  The combination of increasing stumpage prices, annual growth, and increased value due to larger size make growing trees a profitable business on private land.
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