In defense of the black walnut tree

The black walnut tree is having a tough time finding the love and respect it needs these days.

Our black walnut trees grow in New York State, so we’ll review the evidence of their ongoing struggle for positive recognition starting there. Check out the presence of black walnut trees in the U.S. Forest Service’s New York Forest Inventory results. Spoiler: black walnut hardly registers, indicating that the tree is not seen as particularly key to the 63% of in-state land considered forest. The first mention of black walnut in this 100+ page report is in the Appendix as a “tree found on key tree plots”, the academic equivalent of “meh”. This New York-focused native tree planting guide simply ignores the native black walnut tree despite practically every long-term resident of central and western New York knowing someone who owns one.  Even more discouraging, most major land grant universities have published articles with titles like “black walnut toxicity”, warning readers that this tree does not necessarily play well with certain others and advising landowners to think twice before considering the black walnut as a landscaping tree. With press this negative, it’s not hard to see why black walnut struggles to be included on everyone’s “favorite big tree” list.

“A thing which I regret, and which I will try to remedy some time, is that I have never in my life planted a walnut. Nobody does plant them nowadays-when you see a walnut it is almost invariably an old tree. If you plant a walnut you are planting it for your grandchildren, and who cares a damn for his grandchildren?”

~ George Orwell


This pattern of digital disrespect through neglect, omission or outright hostility would lead the curious dabbler to believe that the black walnut just isn’t a desirable tree. It’s messy. It’s unfriendly to other plants. The incentives to plant black walnut trees aren’t obvious unless one’s goal is to grow valuable hardwood to probably benefit the grandkids or someday-grandkids. So how does this apparent black walnut apathy-at-best reconcile with information which links the Haudenosaunee (the Native American nations more commonly known as the Iroquois Confederacy and whose historical territory was upstate New York) to black walnut advocacy? The key research finding is that black walnut trees were often observed around Haudenosaunee village sites or even, as has been suggested, almost exclusively within 5 km of village sites. Such a distribution pattern would suggest a prized tree, not a problem tree. These findings suggest that people went out of their way to make sure black walnut trees had a competitive edge over other trees and were easily accessible to the people who cared about them. Black walnut tree biology hasn’t changed that much over the last few hundred years, so what did change … and is it important now?

Travel back about 300 years in your mind to a Haudenosaunee village and consider what day-to-day worries would dominate. The Haudenosaunee needed to be able to survive cold winters without electricity, synthetic insulation, long-distance transport, furnaces, stoves or other amenities now considered necessities and supplied by the global economy. Their bodies would need more energy, not less, during the cold months and available to meet this need would be such food reserves as they had been able to produce and preserve plus any anything additional that could be obtained through ongoing hunting and/or fishing. Black walnuts are rich in oil, grow without the need for care and once husked but not shelled will stay good for months if not years. The only way nature could design a better winter survival food would be to make it easier to get the nutmeat out of the shells and to make annual yield more predictable. The Haudenosaunee baked black walnut nutmeat into cornbread and simmered the cracked nuts in water to extract oil. It would be interesting to know whether villages with more black walnut or other kinds of nut trees nearby managed the winter better than those without.

That was back then. If Americans now face hunger they are more likely to associate this problem with the economy or politics than winter. Our great challenge isn’t making it through the cold season, it’s figuring out how we will manage the collective resources of the country in a manner that supports people and doesn’t continue to degrade the ecological systems on which we depend. Here again, with this present-day challenge, the black walnut tree can assist but only will if we, like the Haudenosaunee, recognize and take advantage of this potential help on offer. Climate-smart agriculture is how we will eventually deliver food security under changing environmental conditions. The currently wide geographic range of the black walnut tree demonstrates that the species can thrive across a similarly wide climate range. Any plant that can produce calorie and nutrient-dense food with no chemical inputs and minimal care should be warmly welcomed as a potential partner in human endeavors. It makes no sense to shun black walnuts because many types of plants won’t thrive near them; this can be easily addressed by letting black walnut trees grow in locations where this trait is not a problem. The black walnut is being subjected to an unfair standard. Consider the number of non-corn plant species that are allowed to thrive in the middle of, for example, a corn field. In comparison, the black walnut is far more forgiving.

We should be rolling out the welcome mat for the black walnut and more actively figuring out additional ways to use this unique North American renewable resource. Modern technology allows us to get more from this tree than was possible for the Haudenosaunee. In addition to food, black walnut shells are used by industry for blast cleaning, polishing, water filtration (oil/water separation) and more. Processed black walnut shells are useful at home, too, with applications which include home cleaning, personal care and making non-skid paint. We’ve figured out how to make stainless steel cleaner out of bar soap and black walnut shells. No matter how they are used, renewable and biodegradable black walnut shells often displace non-renewable alternatives without sacrificing performance. It’s impressive that one plant can produce high-quality food, raw material for industrial and household products, grow the national hardwood resource base and enhance animal habitat all at the same time and do this using mostly non-agricultural land and no synthetic chemical inputs. The fact that most black walnuts are left lying on the ground every year is proof positive that we’ve hardly begun to realize the value which could be extracted from standing black walnut trees, let alone black walnut trees yet to be planted.

“Early colonists soon discovered the eastern black walnut, (juglans nigra), a native to North America. The great dimension of the trees made it a conspicuous marker of the fertility of the land.” (McComb Daily, 2014)

Far more than many other tree species, black walnuts need people. Black walnuts trees seeded without human intervention are only found near other black walnut trees because squirrels bury nuts close to where they find them. Shade-intolerant young black walnut trees can’t successfully compete underneath a well-developed forest canopy. Therefore, the area for black walnut tree expansion without human intervention is limited to disturbed areas which could eventually become forest (areas with few trees but enough rain to support trees) and near where black walnut trees are already growing. There’s a lot of competition for these types of spaces and, as it turns out, most of the competition grows faster than black walnut trees.

When we harvest the best trees and leave those less desirable standing, we promote survival of the less fit.

The vast majority of standing black walnut trees are owned by farmers and miscellaneous private individuals, in sharp contrast to the conifer forests of the Unites States which are largely owned by the United States Government or commercial forest products companies. This means that long-term black walnut success really is a tree popularity contest. What happens on the land of today’s tree owners is what will write the future story of the black walnut. Whether the black walnut population will grow or decline is likely a function of how much current tree owners like their black walnut trees. If the broad spectrum of individuals who are black walnut tree owners don’t like their trees, the fate of the species is sadly predictable.

We’ll know that the tide has turned for black walnuts when people see them on the ground and think “resource” not “yard waste”. Not everyone thinks “yard waste”. Hammons Products Company, in Missouri, processes roughly 25 million pounds of nuts annually and most of those are grown and gathered by independent growers located within a few hundred miles of their processing plant so those tree owners must see their black walnuts as a resource. Our company, Black Squirrel Farms, is a tiny little company in New York with about 80 mature black walnut trees of our own but we are running a local 2020 black walnut collection program to serve nearby growers and if you’ve got mature black walnut trees in the Finger Lakes area of New York, we would love to have you join our program. Even if you don’t have black walnut trees or live in the Finger Lakes area of New York, you can help. Eat black walnuts; we’ll have shelled black walnuts for sale online in Fall 2020 but our supply will be limited and if you can’t buy them from us, buy from someone else. Give some of the non-intuitive uses of black walnut shells a try, like our anti-skid additive for paint. Help us find and publish new and heritage black walnut recipes; is on the lookout for this kind of information. Let’s make the black walnut popular again, 300+ years later.

It may turn out that in the long run we need black walnut trees as much as they need us now.

NY Finger Lakes 2019 Black Walnut Yield: Down But Not Out

It was late July, 2019 and a normal Finger Lakes summer. The water temperature in Seneca Lake had morphed from threatening into almost pleasant, a handful of boats were out on the water and, for the first time, we were busy readying Black Squirrel Farms to accept black walnuts for fall processing. Our 2019 plan was to grow and process the black walnuts from our 80+ trees on 590 State Route 14 and collect and process black walnuts from other area growers. We were so focused on what was happening on the ground that it took us until July to notice that this year our trees didn’t seem to be growing black walnuts.

Our trees looked healthy, with green leaves and no obvious widespread insect damage so we ruled out an unidentified infestation or disease as the likely cause of our production deficit. We opened some early-falling walnuts and found partially formed shells and black glistening masses instead of nutmeat. Underdeveloped walnuts falling early can indicate insufficient pollination. While there are many ways pollination can go wrong, most are related to weather and the weather irregularity most likely to cause widespread loss is temperature. Spring temperatures below 26°F will kill emerging buds and destroy catkins and pistillate flowers.

A review of Penn Yan airport weather station data revealed that exposure of our trees to temperatures of 26 F or below could have happened as late as April 29, 2019. This is unusually late for temperatures this cold. Logically, if the April 29 cold snap caused our walnut deficit, other area growers would be similarly affected. To test this, we reached out to regional black walnut growers in late July and early August. The map below compares black walnut yield estimates from these growers with the April 29 temperature lows from NOAA monitoring stations. Without the benefit of sophisticated climate modeling to guide us, we crudely defined two areas probably exposed to temperatures cold enough to damage vulnerable non-dormant black walnut tissue on April 29.

Figure: April 29, 2019 Low Temperatures and 2019 Black Walnut Yield at Selected Sites



It’s not clear that sites within this cold exposure zone on fared significantly worse than sites outside this zone. “Maybe a little” is a fair response to that question. It does appear that sites nearest the largest and the deepest of the Finger Lakes, such as ours, fared demonstrably worse.

Even if it the cold temperatures on April 29 did inhibit 2019 black walnut yield, how that happened is likely not as simple as “our blooms froze”. We couldn’t find many reasons to believe that our trees were blooming on April 29 and we hadn’t been monitoring our trees. The information we found signaled that a mid-May bloom date is most likely for our site. For example, a still-cited 1915 article indicates that black walnut trees flower in early April in the southern portion of their North American range then progressively closer to the beginning of June at northern sites like ours. In contrast and confusingly, Wikipedia suggests that black walnut budbreak travels north to south, governed by a 14-hour day length requirement for leafout. Interestingly, this implies first leaves by the end of April and blooms in mid-May for our site. Some excellent 2002-2006 work done with multiple cultivars in New Franklin, Missouri reveals a preponderance of mean pistillate flower bloom dates in mid-May. Both our site and New Franklin, Missouri are in USDA plant hardiness zone 6a, so this study signals mid-May blooms for our trees by analogy. Certainly, trees experience annual variability in bloom date. While we don’t know how much annual variability is normal for black walnuts, the well-documented long-term bloom history of Washington D.C.’s famous cherry trees shows that while cherry tree peak bloom dates often vary by more than two weeks from one year to the next, peak bloom more than ten days earlier or later than the long-term average is possible but unusual. Earlier blooming in recent decades has been widely noticed for many northern plant species but the New Franklin work is recent enough to have inherently taken this into account. This information taken together makes it seem implausible that our black walnut trees were blooming in late April and therefore had blooms susceptible to the cold snap.

Do black walnut trees near the largest and deepest of the Finger Lakes bloom earlier or later than other Central New York black walnut trees? Could our trees have lost their first set of emerging leaves to cold and then, rather than expend already-depleted starch reserves on a nut crop, used their depleted energy supplies to create another set of leaves? Our takeaway is that until we can observe black walnuts growing, it makes sense to assume that the scale of that year’s black walnut crop is unpredictable. Year to year variability in local and regional black walnut yield is almost certainly driven by more than just the alternate bearing nature of the trees. We are responding to this year’s disappointing yield by deferring some of our 2019 plans until 2020 and moving multi-year black walnut storage capability from our “nice to have” to our “need to have” column. Perhaps the science enabling us to predict black walnut yield earlier than a few months before harvest will emerge but until then we will treat an unpredictably fluctuating crop volume as just another known business challenge.

A toilet cleaning fairy tale

Once upon a time, there was a home with a toilet. That toilet needed occasional cleaning. This was a job none of the good people who lived in the home really wanted to do. Then, from the depths of the supermarket aisle for cleaning supplies, a hero arose to take on that very challenge. Just by squirting it on or letting it fizz or dropping it in the tank, this hero would cling/foam/dissolve/shine/coat/disinfect/deodorize to bravely fight toilet-dwelling life forms and stains of all origins, leaving the bowl sparkling clean for the good people of the home. The battle line between good vs. evil was drawn and the enemy was beaten back to a position of retreat located somewhere downstream of the flange in the bathroom floor. Our hero was victorious and is happily affordable enough to be with the good people of the home forever after.

And that’s the end, right?

This compelling story has been told many times. However, one feature of stories is that they often require the listener to suspend disbelief in order to enjoy the story. What realities lurk uncomfortably behind the scenes? It’s time to have a look at some of the plot holes.

Plot hole #1: The toilet (or toilet seat) is the grossest, dirtiest thing in the house and therefore fighting that monster with the more powerful weapons available makes sense.

A lot of work suggests that toilet seats are generally quite clean compared to household items like toothbrushes and toothbrush holders, bathmats or (possibly the worst), used kitchen sponges or dishrags. Interestingly and arguably, one of the most effective steps that can taken to minimize the spread of household toilet-related germs is to flush with the lid down and then lift the lid back up to let it dry post-flush. Flushing makes a small fraction of toilet water go airborne and toilets are most often flushed when their contents are less than pristine. How tough the bad guy in our story is may not be related to how tough the bad guy looks.

Plot hole #2: Potent chemicals either disappear or become harmless once flushed and so our hero will never become a villain.

Our story doesn’t state this but it is implied. Most chemicals capable of harming or killing life don’t stop being chemicals capable of harming or killing life just because they happen to be flushed down a toilet. Perhaps instead of a good guy/bad guy story, the more honest tale would be that of Dr. Jekyll and Mr. Hyde – the same character with a dual good and evil nature. Check out what the Environmental Working Group has to say about the product you are using now. Over half of the toilet cleaning products on the market score an “F” on their hazard rating scale.

Plot hole #3: Our hero is simple and well understood.

Because of trade secret protection laws, cleaning product manufacturers don’t have to list all ingredients on their label (although some manufacturers commendably do). What is federally required is that household cleaners containing chemicals of known concern name those specific chemicals on their label and include a warning detailing associated risks plus caution statements and first-aid guidance. What if a chemical concern isn’t known? Much more testing has been done to assess risks from acute versus chronic chemical exposure as well as quantify hazards associated with single chemicals versus chemical combinations. The hero of our story is more complicated character than portrayed.

We’re telling a different story. The composition of our toilet-cleaning product isn’t a trade secret – we make our product using baking soda and black walnut shell powder. Our product includes no fragrance of undisclosed origin and no disinfectant. Finely ground black walnut shells act as an abrasive hard enough to effectively clean but soft enough to not scratch porcelain and concurrent scrubbing with an abrasive enables a mild, non-toxic cleaner like baking soda to be more effective. Our product is intended to be part of an integrated cleaning regimen, not a solution for everything. For those who have taken control of their home cleaning routine to such a level that they make their own cleaners, we offer black walnut shell powder as a separate ingredient. There are no plot holes in our story about offering a non-toxic septic-safe aquatic-life-friendly toilet cleaner which includes a biodegradable abrasive made from 100% American-grown black walnuts. We believe that people should know all the ingredients in the household cleaners they are using so that they can make informed choices regarding how they want to clean their home. It’s easy to learn about us. We aren’t complicated and we believe that the more people get to know us, the more they will choose to work with us – and that’s our happily ever after.


Can I put black walnut shells in my recycling bin?

What should go in recycling bins is exactly what the destination facility knows how to process. If the facility receiving the recycling bin contents only knows how to process cardboard, newspaper and aluminum cans and instead they receive coat hangers, those coat hangers are no longer coat hangers but rather “contaminants”. Contaminants are generally diverted to a landfill.

Of course, those same coat hangers holding up clothes in a closet aren’t contaminants. When they are doing their job, they’re coat hangers. Just like some people say that a weed is a plant out of place, waste can be a resource out of place.

At Black Squirrel Farms, we have some ideas about how black walnut shells can be a resource and not a waste and we are proving it by bringing new products to market. Check out our store. Alternatively, consider upcycling black walnut shells. Search on “sliced black walnut shell art” and be amazed.


Are black walnuts and English walnuts different and do English walnuts come from England?

It’s likely that when someone says “walnut”, you imagine an English walnut. The walnuts sold in grocery stores are mostly English walnuts. Black walnuts are available for sale but they are hard to find. Black walnuts and English walnuts have different flavors and shapes. Black walnuts have a bolder taste, with more fruity and musty flavors than English walnuts. The strong flavor makes black walnuts a more attractive ingredient nut as opposed to a snack nut. The less earthy flavor of the English walnut has broader appeal and English walnuts make a great snack. English walnuts have thinner shells that are easier to crack with a higher nutmeat/shell ratio (more meat per nut).  English walnuts are more easily shelled at home with a hand-operated cracker.


Both kinds of walnuts are really healthy foods. Walnuts contain alpha-linolenic acid (ALA), the plant-based source of omega-3 fats. Both kinds have been found to contain phytosterols, a cholesterol-lowering agent. Walnuts are low in saturated fats and high in fiber. Proportionately, English walnuts may have a little more omega-3 than black walnuts but not as much arginine and selenium. There is no wrong answer when trying to choose the healthiest kind of walnut.

Black walnuts are native to North America. But are English walnuts native to England? As it turns out, English walnuts grow in England but that’s not where the tree originated and English walnuts are not a major English commercial crop. The tree originated in the Middle East and the nuts are called English walnuts because historically the English merchant marines would trade them around the world; the nuts became commonly known as English walnuts. The English walnut and the Persian walnut are the same walnut.

Black walnuts are an heirloom American ingredient. Because they have a different flavor than English walnuts, they cannot be substituted 1:1 in recipes calling for walnuts without affecting the recipe outcome. Heirloom ingredients may require heirloom recipes or the creation of new recipes. Here’s a fun example from Sheryl Lazarus, who posts and tries family recipes from a hundred years ago and has noticed that trying these recipes has caused her to eat healthier foods made with local, seasonal ingredients.  Got your own heirloom black walnut recipe over 100 years old?  Please contact us to share.