Tree thinning on the west coast

Having spent a great deal of time hiking and skiing in Northern California and the Pacific Northwest, I have grown quite fond of the beautiful scenery out there. I suggested to my friend Tom that I might write a short article on his travel blog about something that will affect peoples’ ability to enjoy the sheer beauty of the region, and that is the wild fires that are burning up huge swaths of pristine and scenic land that will take decades to be reforested.

My name is Steve Portnoy and I have been working in the tree trimming and removal business for a couple decades. Back in the late nineties and early two thousands, I spent a great deal of time travelling up and down the west coast camping, fishing, skiing, and hiking with my wife Belinda and a friend from high school named Suzanne and her husband Nick, a contractor in the roofing business. They enjoyed being out in nature as much as we did, and we all grew very fond of the unique geography of the West Coast.

While Belinda and I still go out from time to time, Nick wound up with arthritic knees, presumably from crawling around on roofs and standing at awkward angles for hours at a time, so activities like hiking and skiing had to go.

Anyway, we spent a lot of time in the woods and all noticed that it didn’t seem there were enough efforts made at thinning the thick and overgrown forests we frequented. Lots of underbrush was allowed to grow unchecked, and dead trees were left to rot and fall. In forestry, thinning is the process of selectively removing trees to allow for the remaining trees to have more room to grow unobstructed and to therefore allow them to be healthier and stronger.

Every 20 or 25 years might be considered frequent thinning, and would allow for the trees to get wider crowns, increasing their diameter and be more resistant to threats like ice breakage or wind damage. If an area is overthinned, which is possible, the site would get too many shrubs in it and prevent what is called the “understory” from regenerating effectively. This also causes an abundance of branches on the trees which makes them knottier. Not doing it often enough will cause the trees to grow tall and slender, reducing their value on the market by creating less wood.

As you might imagine, our country uses a tremendous amount of wood and wood products, like paper, in construction and in our day to day lives. Forests are the source of all this wood. While it may sound cruel, growing trees for the primary purpose of cutting them down and using them for the advancement and growth of society is a noble and just cause, kind of like raising cattle. So the object here is to grow trees that are best suited for this purpose. There are several methods for thinning, and the effectiveness of each method is highly dependent on individual site conditions and species mixes and responses. This is definitely not a one size fits all activity.

There are really 5 methods for thinning. I will briefly discuss each.

  • free thinning – this basically means thinning around a desirable tree. In some cases there is almost nothing to remove and in others a lot of thinning.
  • geometrical thinning – this is mostly done on tree farms where the trees are planted in rows, and by design one row is taken out periodically to make room for the remaining trees to thrive regardless of the condition of each tree.
  • thinning from below – this is done entirely around the base of the tree and can range from light thinning that removed all over-topped trees all the way to heavy thinning which removes anything that might affect the growth of the desired tree.
  • thinning from above – this removes all the trees that have an impact crown-wise on other similarly-sizes trees.
  • diameter thinning – large trees exceeding a pre-determined diameter are cut down for the benefit of smaller trees which are in good shape. This process can go on and on until the all valuable trees have been harvested. At that point the remnant is clear cut and the process begun again.

All of the methods above are used to great effect when employed properly. Our appetite for wood is insatiable here in the USA and we need all the creative ideas we can muster in order to provide all the wood we can possibly produce without damaging or destroying our valuable forests. In fact the thinning methods mentioned are done to protect forests from fires and pests that might otherwise destroy thousands of acres. We have seen firsthand the destructive power of fires on the west coast. The amount of wood lost to these fires could have built tens of thousands of homes but instead went up in smoke. As a friend in the fencing business said to me convincingly, we are much better served to over-thin rather than under-thin. Stopping these fires before they really get big should be out number one priority in our forest management efforts.