Jonas Frei 
WALNUSS 
Alle in Mitteleuropa kuliivierten Arten 
Botanik, Geschichte, Kultur 
butternuts that started my interest in this 
exceptional plant family. He states that a but- 
ternut tree was planted in 1887 at exactly the 
spot where I found the nuts pressed into the 
soil. Now I know that these nuts, almost like 
modern-day fossils, are the remains of a now- 
rare species. The tree was planted long before 
butternut canker was imported to the United 
States, and before hybridization with imported 
species changed its natural populations rapidly. 
If we did not have our own hands in all the 
processes that threaten species like the butter- 
nut, we could analyze the consequences from 
a scientific perspective and see with great fas- 
Juglandaceae 17 
The author’s book Die Walnuss—currently available in a German-language edition—features drawings, photographs, and 
descriptions of the walnut family. 
cination how some species emerge from this 
immense pressure and how others disappear, 
just like during the whole history of this fam- 
ily. But we also have a responsibility towards 
biodiversity, towards those species that exist 
now and that enriched the global ecosystem 
long before the arrival of humans. Today, as the 
pace of ecological change and movement con- 
tinues to accelerate, we have to recognize that 
the story of the walnut family is now entwined 
with our own. 
Jonas D. Frei is a landscape architect, documentary film- 
maker, illustrator, and author from Ziirich, Switzerland. 
