Walnut is one of the oldest trees known to mankind since prehistoric times.
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Some walnut trees, according to the calculations of the dendrologists, are at the age of about 1000 years. Old walnut trees adorn with their impressive height and wide green crown many places all over Bulgaria. Walnut tree generously gives us over 100kg of fruit from our tenth year. Its fruits are wrapped in a tender soft green envelope which leaves the inner layer of the germ, the so-called endocarpium - the shell, and the botanists define the walnut as a stone. Inside is a kernel - a two-part seed, each divided into two.