Brad Withrow-Robinson, Forestry & Natural Resources Extension Agent, Benton, Linn and Polk Counties.
In a previous article , I wrote that many folks in NW Oregon are growing too many trees in young stands given some common family forest landowners’ objectives, including doing a commercial thinning when the trees are in their mid 20s. Since most people are hoping to do a commercial thinning on their way towards a variety of longer-term objectives and stand conditions, we need to focus on reaching that first commercial thinning in a timely manner and leaving the stand in a good condition to meet future objectives. Let’s begin by looking at what it takes to have a commercial thinning.
My contacts in the business around the mid-Valley tell me that while the first thinning should provide a mix of saw logs and chip logs, most of the surplus trees removed in the thinning need to produce a sawlog or two if you hope to break even or make a little money (a mix of around 2/3 saw logs and the remaining 1/3 chip logs is a rule of thumb used by some). Too many small logs and you are losing money. That sawlog will vary according to the mill it is headed to, but is generally 20 feet to 32 feet long with a 6 or 7 inch top. Smaller wood goes to chip and saw or pulp.