By: Anthony C. Arnoldi, Certified Arborist
Pines are always highly sought after to provide year-round green screening from undesirable views and to provide a needed sense of life in an otherwise bleak winter landscape. However, a very prevalent fungus disease of the needles, twigs and branches often makes its appearance on these valuable plants. It mars the appearance with browned needles and branch tips, later progressing downward and further into the plant. It is called Sphaeropsis, the scientific name for this fungus. It is the most serious disease of landscape pines and needs to be addressed when it appears. Two aspects of control are important:
- a 2- or 3-spray application program replaces protective fungicides on the needles and shoots as they form and elongate in spring. This blocks infection by the fungus during the critical time when its spores are in the air.
- pruning out the infected twigs, shoots, branches and cones. Fungus growth progressively kills more tissue and this infected material produces more fungal spores that infect more twigs. This type of pruning is known as sanitation pruning and is a very important aspect to controlling diseases such as Sphaeropsis.
When pruning of this type is done, it is important to:
- be thorough
- sterilize the pruning tool between each cut so as to prevent spread by contaminated blades
- include pruning off the cones, where practical, and also pick up fallen cones as the fungus tends to build up in them, later releasing many spores
- cut beyond the browned parts to be sure the fungus has been pruned out— it can be several inches “ahead” of the dead tissue.
If done properly, this pruning will help control efforts to be longer-lasting, while greatly reclaiming the lost aesthetics. The fungicide spray program is very important to allow replacement needles to stay green and restore beauty to your pines. Call your Wachtel Certified Arborist for an assessment to help you with this important task.
© Copyright 2004 – Wachtel Tree Science & Service, Inc.