On Tree Day – a celebration that reminds us of the importance of trees for nature, climate, and culture – we are pleased to announce that an extraordinary symbol of life, endurance, and scientific passion has been planted in front of our Institute building at Wieniawskiego Street 17/19.

This unique clone of the Rus Oak from Rogalin is a gift from Prof. Paweł Chmielarz from the Institute of Dendrology of the Polish Academy of Sciences.

The Rus Oak is one of the oldest oak trees in Poland. It was propagated in vitro at the Institute of Dendrology PAS, where a method for cloning pedunculate oaks (Quercus robur L.) was developed. Research on the micropropagation of ancient oaks in sterile in vitro cultures was conducted at the Institute of Dendrology in Kórnik under the supervision of Prof. Paweł Chmielarz between 2013 and 2017, and financed by the General Directorate of State Forests in Warsaw. The cloned oak possesses an identical genotype – both shoot and root – to the parent tree.

Monumental pedunculate oaks in Poland are valuable not only for their resilience to changing environmental conditions but also for their cultural and historical significance. Among the native oak species found in Poland, the pedunculate oak is the most common, accompanied by sessile oaks (Quercus petraea) and downy oaks (Quercus pubescens). However, preserving their genotypes is challenging – traditional vegetative propagation methods, such as rooting woody or herbaceous cuttings, have proven ineffective, and grafting does not yield genetically identical plants. Generative propagation from seeds also cannot preserve the individual DNA of the parent trees.

Scientists from the Institute of Dendrology PAS examined twenty several-hundred-year-old trees and applied in vitro micropropagation, a method that allows the production of genetically identical individuals from small fragments of shoots or leaves. This approach relies on the phenomenon of plant cell totipotency – the ability of a single cell to regenerate an entire plant. The process involves culturing tissue fragments under sterile conditions on media containing appropriate nutrients and growth regulators, including plant hormones.

After the multiplication (regeneration) phase, young plants undergo acclimatization – a particularly difficult and critical stage for their survival. During this process, the plants are gradually adapted to natural environmental conditions, including variable humidity and exposure to microorganisms in a non-sterile environment. Successful acclimatization requires many years of experience and precise control of cultivation conditions.

Trees like Rus are of great cultural, historical, and biological value. The propagation method developed by scientists in Kórnik can serve to reproduce and protect native oak species – especially those distinguished by exceptional resilience or vigorous growth. We warmly congratulate the team from the Institute of Dendrology PAS on this remarkable achievement and sincerely thank Prof. Paweł Chmielarz for this extraordinary gift to our Institute!