Update on Native Butternuts and Chestnuts in Princeton

There's a lot of gratitude being expressed towards trees these days. The gratitude tends to be towards trees in general, but this fall, I'm especially grateful for three trees in particular. 

All three, growing at the TRI property, are among many that have been planted over the years by local nut tree expert Bill Sachs and me as part of an effort to bring back two marginalized native tree species. One is an American chestnut. The other two are butternuts. Both of these species have been laid low by introduced diseases, and I feel fortunate to be part of an effort to make them numerous once again in Princeton. 

The two butternuts at TRI bore a bumper crop this year, some 200 nuts--the first sizable harvest since the parents to these two trees were lost 14 years ago. One fell in a storm; the other ironically was cut down as part of an environmental remediation. It's Bill who played the role of Noah, growing new seedlings from the seeds we collected from the two trees before they were lost.

We planted other members of this new generation of locally sourced native butternut trees at Harrison Street Park, Herrontown Woods, Mountain Lakes, and Stone Hill Church. Bill in particular did a lot of the followup work, checking the cages that protected them from the deer, and serving as a one man bucket brigade to sustain the trees through droughts in their first couple years.

Bill also did a great deal of work to re-establish native chestnut trees in Princeton. That project began in 2010, when chestnut researcher Sandra Anagnostakis, of the Connecticut Agricultural Experiment Station came to town to give a talk. She brought along 20 chestnut seedlings for us to plant in local parks. The seedlings were 15/16th native, 1/16th Japanese chestnut. Of all of those that Bill planted, at the Princeton Battlefield, TRI, Herrontown Woods, and Harrison Street Park, only the one tree at TRI has borne fruit. Many of the hybrid trees have died, despite the effort to breed in resistance. 

There have been some other efforts to get the American chestnut growing again in Princeton, by the Friends of Princeton Open Space at Mountain Lakes and also by arborist Bob Wells at Greenway Meadows. The best bet for repopulating our world with the American chestnut may well lie in research that led to inserting a gene from wheat into the American chestnut genome that confers resistance. This seems a much more dependable and faster way to embed resistance to the fungus, and bring back this spectacularly useful native tree. 

In the meantime, we can celebrate the hard-won harvest we're getting from this new generation of native nut trees, and after letting them cure a bit will even get to find out what a butternut tastes like.

Related posts

From 2021: Butternut Redux--A New Generation Bears its First Crop

From 2010: The American Chestnut Returns to Princeton

Lorenz Hiltner--Plant Scientist and Potential Relative

A few years ago, my brother, Bill Hiltner, got interested in running a farm-scale composting operation near where we grew up in Wisconsin. Having degrees in physics and chemistry, he's the kind of guy who would be drawn to wondering what actually goes on inside a compost pile. Before long, he came across the research that another Hiltner had been doing a century prior. 

Lorenz Hiltner, according to an article published in the professional journal Plant and Soil, was "a pioneer in rhizosphere microbial ecology and soil bacteriology research" and the first scientist to coin the term "rhizosphere," back in 1904. 

"Due to Lorenz Hiltner's research on the biological basis of soil fertility, which places soil organisms and the humic content of soils in central focus, he is recognized today as one of the founders of applied microbiology and organic farming."

One of the founders of organic farming? A Hiltner? Not that we've managed to trace any clear genealogical link, but maybe some inherited genes inclined me to start growing organic vegetables in high school, and then teach organic gardening at a summer camp called Innisfree in northern Michigan. Maybe it was some sort of genetic echo that caused me to read the 15th printing of Rodale's Encyclopedia of Organic Gardening as if it were a bible, and revel in the richness and earthy aroma of leaf mold three feet deep where the landscape crew at Yerkes Observatory had deposited big mounds of leaves each fall for decades. Or maybe it was just coming of age in the 1970s. 

Lorenz Hiltner "was born on November 30, 1862, in Neumarkt, Upper Palatinate (Oberpfalz), Bavaria, as the first son of a master in acetic acid fermentation and gastronome." A Wikipedia entry describes his father in less lofty terms, as "a vinegar maker and innkeeper." By 1885, Lorenz had completed his academic studies, and in 1896, he and a colleague patented a means of "'vaccinating' legume seeds with pure cultures of nodule bacteria," according to wikipedia. The inoculant was called "Nitragin."

Most of his research he performed in the Bavarian Agriculture-Botanical Institute in Munich, where he was the director from 1902 to 1923, building the institute from four employees up to 90. The Institute's mission was to support agricultural practices in Bavaria, but scientists came from all over the world to learn from his experience. According to wikipedia, "Until 1904, his institution was the only place in the world that supplied "vaccine bacteria" to farmers. At the 1904 World's Fair in St. Louis, Hiltner and his Agricultural Botanical Institute were awarded a gold medal." (Note: The article and wikipedia both say St. Louis, Michigan, but the Worlds Fair that year was in Missouri.)

Another quote from the article makes him sound particular relevant to today's intense interest in the give and take between tree roots and other life in the soil. While we focus on how trees and other plants support life above ground, it would seem they also give as much as they get from the soil beneath them, sending the overabundance of their photosynthetic production downward to feed soil life. 

"Hiltner became convinced that root exudates of different plants support the development of different bacterial communities. His definition of the rhizosphere in the year 1904 centered on the idea that plant nutrition is considerably influenced by the microbial composition of the rhizosphere."

Lorenz Hiltner was part of the great European tradition of cutting edge research that was the envy of American scientists early in the 20th century. In researching the lives of my "adopted ancestors", American mathematician Oswald Veblen and atomic physicist Walter Colby--both of whom traveled frequently to Europe as the century began, wishing to emulate the great institutions of learning they found there--I see a contrast in trajectories. As the U.S. rose in prominence and innovation, European scientists became increasingly hampered by political conflict and instability, even before the Nazi rise and WWII. 

Always working to advance research and apply it to people's everyday needs, Lorenz Hiltner sought to make the best of the worsening political conditions. During WWI, he "conducted intensive studies on alternative food sources for men and livestock to prevent disastrous consequences of the famine in Germany." "After the war, he managed to start his scientific journal again in 1921 despite the problems with the unstable situation and ongoing revolution and counterrevolution in Munich."

His scientific contributions were deemed worthy of a centennial symposium. From the article: 

"In the centennial symposium of Hiltner’s definition of the “Rhizosphere” in Munich in September 2004, more than 450 scientists gave tribute to his founding work on the rhizosphere and presented studies that continue on many of the ideas first brought to light by Hiltner."

He died unexpectedly, of a stroke while in his office, 100 years ago at this writing, on June 6, 1923. His work was continued by his eldest son, Erhard. Regardless of whether we discover an ancestral connection, I'm feeling some kinship.