Sometimes in life it is the bad things that happen that really teach us lessons we otherwise would never have learned. In this case, I am talking about a 180-year-old barn with a lot of character. It was in sad shape when I bought the property – or at least one side of it was. A few months ago, I noticed one of the walls was starting to cave in! This began my lesson on the American Chestnut. 

A good portion of the rotted 7×7 barn post that was cut out during my recent barn-saving repair. Photo by mrl2022.

The American Chestnut used to be plentiful in the American landscape. It was roughly found from Maine to Louisiana, staying away from the southeastern coastal United States. Here in Connecticut, it was plentiful. My barn was built largely out of Chestnut, as were many in the countryside. Long before I was responsible for it, water infiltration and termites took out a back-corner post and two of the main structural beams. Only something built in the mid-1800s could still be standing given that description. I am part of the way through replacing the missing and/or rotten framework. It was during this time that I developed a respect for this species of tree.

Even though there were beams over half way rotten or eaten, they were still incredibly strong.  From my observation, the wood does not behave the same way as other modern-day lumber.  Even when only one third of the beams are left, it was extremely difficult to cut through. It is a very hard, dense, strong, and most of all a highly rot resistant wood. In fact, there are pieces that are in contact with the ground that are still solid in both my barn and house. Now I have no way of knowing for sure if some of the ground pieces were replaced, but I do not see any evidence of it.

Even though the wood was largely rotten and riddled with insect damage, it was the hardest wood the author ever had to cut through. Photo by mrl2022.

The American Chestnut was used for building houses, barns, fence posts, animal housing, furniture, and just about anything else one can imagine. The bark is reportedly medicinal for coughs, arthritis, and a sore throat. The chestnuts themselves, like a famous holiday song suggests, were good to eat when roasted over an open fire. I have read about farmers turning their cattle and hogs loose in the forest in the fall to enjoy the fallen nuts. I can only imagine how many native wild animals used it as a food source as well. All in all, it seemed like the absolutely perfect tree. Then, in the early to mid-1900s, the Chestnut Blight wiped out most of them. It is a type of fungus that kills the above-ground portion of the tree. Many times, the roots below ground remain alive. They send up shoots that only live five or ten years max before they too die off. This stump sprouting is another beautiful aspect of this tree species. When they were cut down for lumber, they would simply send up another shoot that would grow into a beautiful tree a number of years later. You did not even have to replant it! 

There is hope, however. There are different organizations and teams of scientists working to bring it back. Some are looking for disease resistant varieties and trying to selectively breed them, while others are trying to genetically engineer resistance to the blight by introducing a gene from a type of grass. Some purists resist such genetic tampering, but I believe the ends will justify the means. There are plans to freely distribute the trees to anyone who wants one once there is a stockpile of resistant specimens ready to go.

So, this brings me to the point of my story. The loss of the American Chestnut was not just an ecological disaster, but one that hit us humans hard as well. We lost one of the most valuable, if not the most valuable, species of tree in this part of the country. As such, humans were forced to replace what nature had provided for us with pressure treated lumber. Pressure treated lumber is treated chemically, under pressure, to produce a product that is rot and insect resistant. It has gone through a number of formula changes over the years. There has been great concern over what chemicals were used in the process. In the past, arsenic was the main ingredient in the wood treatment, but copper is now the main ingredient used (except in marine applications due to toxicity to marine life). Either way, boards that are rated for ground contact contain much higher levels of the chemical preservatives. The newer formulation does not possess the same risk as the old. It can be used for playscapes and furniture, but is not recommended for food contact. This leaves a bit of a gray area when we consider its use in raised garden beds or chicken coops. Much of the school of thought says that it is generally safe to use, but I don’t use it for these purposes. So many times, something thought to be safe ends up not being so. It is extremely difficult to determine what amount of leaching of the chemical preservatives does enter your garden soil, and how far they may migrate from the source. A lot will depend on the various soil properties, chemistry, hydrology, and other biotic and abiotic factors. Being that plants indiscriminately take up elements from their surroundings, you could be eating some of the preservatives. Chickens tend to scratch up the soil and move it all around, so they could be coming into contact with the preservatives as well. If you eat the birds and/or their eggs, you could be exposed so some small levels. Remember that these chemicals are actually toxic to life.  That is why the wood isn’t eaten by insects or rotted by bacteria or fungi. I am in no way trying to alarm anyone or imply that there is an enormous danger. I do know many people who have used it in agriculture, and it is generally considered safe to use in these manners.

I personally use some kind of alternative for anything I will consume, like vegetables and chicken eggs. There are a number of rot resistant woods on the market that you can use in place of treated lumber. They are not nearly as rot resistant as Chestnut, but they have varying levels of resistance. By and far the best of the remaining woods is Cedar. This can last an extremely long time. The downside is the exorbitant cost. I used to use it in certain instances, but since the lumber price hikes during COVID, I have not seen this being a feasible option. According to a manager at a local big box lumber store, the company does not stock cedar anymore due to the price – consumers and just not willing to pay that much. Redwood, cypress, and locust are also better at resisting rot, but they can be more costly and harder to come by as well. You will have to price things out if you have a project in mind. Lumber prices fluctuate frequently. 

My recommendation for raised garden beds and chicken coops is Douglas Fir. This wood is somewhat rot resistant. This is the slightly red colored wood you will see in most box stores. It is widely used in construction. I have used it in ground contact for a number of animal housing projects and got 15 years or more out of it before it started to significantly break down and need replacing. I have done this in a number of locations and soil types, both wet and dry, and have had really good luck. The advantages are much lower cost, it is readily available, there is no risk of chemical consumption, and it has a decent life expectancy. Couple this with the statistic about how often people move, and you are more likely to sell your home before you would have had to replace your chicken coop or raised garden beds. Even if you stay put, you most likely will only replace the wood once or twice. The only exception I make to this rule is fence posts and barn posts and beams. These I see as structural components, and here the greatest risk would be failure of the lumber components. As such, I used treated lumber in these places.

Douglas Fir being used in a ground-contact situation for a chicken coop. The author gets about 15 years out of the wood used like this. Photo by mrl2022.

Overall, you have to decide what is best for your particular situation. There are many factors that go into picking the right wood product for the job. Cost, aesthetics, longevity, type of use, and years of expected use are just a few. I really hope science can figure out a successful, permanent solution to the Chestnut Blight. It would be great to have a future where our children can use American Chestnut trees the way our forefathers did.   

Matt Lisy