Southern Maine Forestry


Forestry News and Updates

High Graded to High Grade

What is the worst thing you can do to a forest? Many would think the answer is clearcutting, but there’s something even worse – high grading. This is the practice of “cutting the best, leaving the rest.” Cutting the best might seem like a good idea. After all, the lower grade trees don’t yield as much return. But what happens is the forest is now runts, culls, crooked stems and less desirable species that quickly take over the growing space. Following clearcuts, new tree growth will most likely include some excellent stems.

What I call slow motion high grading is what some loggers use when they are trying to emulate the work of quality foresters’. It may look better than a typical high grade cut, but it might actually be worse. When a forest is cut hard, some of the better trees will probably regenerate. But if a series of lighter cuts are made and only the larger, more valuable stems are cut, you end up with a forest full of lousy trees. And often regeneration composed of hemlock, beech, balsam fir and soft maple sprouts.

So how long will it take a forest to recover from high grading? The short answer is that it never will. Sure, with time and culture, the better stems can achieve high grade potential, but when you selectively take the best trees and leave the other stuff to grow unattended, you never get the forest back to where it could have been if better forestry practices had been utilized.

Let me give you an example. We have managed a lot on a well traveled highway since the mid-1980s. We often get compliments on the appearance of this lot. When I first visited the lot, a logger had high graded it in the late 1970s, cutting most of the white pines and red oaks of sawlog size.

We were hired after a storm which damaged some of the residual timber in 1985. We had the damaged timber salvaged and some of the worst quality residual trees cut. Since then we’ve had improvement cuts done on the property in 1996 and 2013. Finally, after three managed cuts, the residual stand is looking pretty good.

Over the years, the improvement cuts and thinnings have brought the owner about $700 per acre in income. The lot currently has about $1,500 per acre in standing timber. When I first saw this lot in 1985, I estimate that it had a value of about $100 per acre in standing timber. That means it’s grown approximately $55 per acre per year in value over 40 years.

That’s not a bad return, but it could be so much better. Let’s compare it to a similar lot that has always been treated the right way. On this lot, three harvest treatments over 40 years have yielded $1,100 per acre. The bigger difference comes from the trees still growing. On this lot, the pine trees were left to grow and are now mature and amount to 10-15 mbf per acre. Add that to the quality stems of other species, and the lot is carrying $4,000 per acre! This lot did have a larger initial value, an estimated $250 per acre. So the annual increment growth has been about $120.00 per acre per year. That’s 120% greater value growth than the forest that was high graded and subsequently well managed.

Understand that these values are higher than average numbers, so you may be able to expect the same results for your land. Both of the lots in my examples have very good soils, and white pine makes up a significant portion of the forests. Locally, this combination of factors brings the best value growth.

A lot with more average soils and more hardwood and hemlock, depleted forests are only growing $10-$15 per acre per year of timber. If these lots are well managed, their potential growth in value is more in the $40-50 per acre per year range.

A forest that has been high graded will never recover its full potential. The depleted overstory stand will need to be replaced with the next generation of trees, which in Maine and New Hampshire can take 50 to 100 years. The bottom line is that high grading your forest is not a good idea!

jeanie Clemmer