In 1973 in Nancy the IUFRO working party "increment determination" had set for itself the task of selecting as one of its chief research projects "Variations of Increment at Various Stem Heights" depending on different stand treatment. During the XVI IUFRO Congress at Oslo a session was held on June 24, 1976,at which the first scientific contributions to this long-term research program were presented. Thanks to the active cooperation of several colleagues I am happy to announce that it is now possible to fulfill the wish expressed in the preface of the second issue of "Contributions to Increment Research", which appeared in the Mitteilungen der Forstlichen Bundesversuchsanstalt No. lo5/74, to continue publications with the third issue of this series. This issue not only includes the contributions to the main field of research "Variations of Increment at Various Stem Heights" but also all the voluntary papers which were presented at the meeting in Oslo or dealt with at the discussions. As Leader of the working party for the last six years I requested the members present at Oslo to entrust the leadership to my colleague, Dr. Klaus JOHANN. We sincerely wish that through the cooperations, assistance, and support of his international colleagues he will be able to continue successfully to extend the findings of this almost inexhaustible question complex "increment" which was initiated in 1961 under the distinguished leadership of Professor Dr. A. KURT.
