Closure characteristics in pruning wounds of five species of landscape trees in South China

Objective Closing process of landscape trees in South China was studied in two years after pruning, in order to explore the closure mechanism of pruning wounds, and provide a theoretical basis for landscape tree pruning practice.

Method Branches in three sizes from five species of landscape trees were trimmed in December 2013. Measurements of the wound closing process were taken every three months from December 2014 to December 2015. Differences in wound closure abilities caused by species characteristics, wound sizes and seasonal changes were analyzed.

Result The wound closure rates of Michelia alba and Mangifera indica were relatively higher (94.80% and 92.38%) compared to other species, and the wounds of 20- < 30 mm and 30- < 40 mm diameters closed faster compared to 10- < 20 mm wounds. The wound closure rates of Syzygium jambos, Bauhinia variegata and Ficus virens were relatively lower (82.23%, 64.95% and 70.99%), and the wounds of 10- < 20 mm diameter closed faster. The wound closure process was generally slow from the time of pruning to March, accelerated from March to June, was the fastest from June to September, and slowed down from September to December in the first year, which was consistent with the changes in tree growth rates during annual growth periods. The wound closure process was slow in the second year.

Conclusion Wound size influences wound closure rate differentially among species. Wound closure rate is closely associated with the tree growth rate