Improvement of grafting procedures for the ornmental species: I. Picea pungens Engelm. var. glauca Regel

In order to get ornamental trees for landscaping, Colorado blue spuce (Picea pungens Engelm. var. glauca Regel) scions were grafted on Norway spruce (Picea abies (L.) Karst.) rootstocks.An original double-side-veneer grafting method was applied in five experimental or basic variants. The plastic tapes and the ecological Ceraltin® wax developed by the Research and Development of Bio-stimulators (CCDB) BIOS Cluj were tested. In addition, two controls in which the classic raffia and the traditional hot wax and the classic side-veneer-grafting method were used. The obtained results, expressed in percents, were transformed in arcsin square root of percent values, and then a two-way analysis of variance (ANOVA) was used. Highly significant (p < 0.001) statistical differences were found between all grafting variants, including controls. The Duncan test proved that original double-side-veneer grafting method and the new developed materials, i.e. plastic tapes and the ecological Ceraltin® wax have contributed in getting a better grafting success compared to the controls.Thus, the double-side-veneer grafting method and the two grafting materials are highly recommended to be used in getting grafted Colorado blue spuce ornamental trees.