White Pine Needle Damage (WPND) is likely caused by one, or perhaps a combination of a few, fungal pathogens. Scientists suspect that excessive spring rainfalls over several consecutive years created the conditions that caused these fungi to proliferate. Other climate- related factors, such as above-average winter temperatures followed by late- spring frosts, may have played a role in the blight.
How can I tell if my white pines are affected? The blight causes mature (one-year-old) needles to discolor and then drop off, which then creates a thinning of the tree crowns the following year.
What can I do to prevent the spread of white pine needle damage? Not much can be done to prevent the premature needle loss, though in some cases preventive treatments can reduce the amount of needle damage for the following season. Happily, the newly emerging, current-season needles appear to be undamaged on many affected trees, and there has been no observed tree mortality from WPND. But since the defoliation does weaken the pines, making them vulnerable to further stressors, owners are encouraged to take measures to protect the trees. Regular application of SavATree’s 100% organic ArborKelp stimulates new growth and forti es root systems, and will help the trees better withstand drought conditions, insects, and extreme temperatures.
, the common term for several species of soft scale insects, feed on the sap of shade trees and woody ornamentals. Scale usually causes little damage, especially to healthy trees. If trees fall victim to extreme or sustained scale infestation, however, some branch dieback, leaf-yellowing, and leaf-drop can occur, and on rare occasions, tree mortality.
How can I tell if my trees are affected?
Since nymphal “crawlers” that hatch in early summer are so tiny, it’s the by-product of scale infestation that is usually the first visible symptom. After feeding on tree sap, scale insects excrete a sweet, sticky material called honeydew. The honeydew drips onto lower leaves and branches – and anything else that lies below, including lawn furniture, roofs, and patios. The honeydew often promotes the growth of an unsightly black fungus called sooty mold. Adult scale is quite visible in cooler months, when they migrate to twigs and bark to feed and cover themselves in immobile waxy shells.
What can I do to prevent the spread of tree scale?
Natural enemies include a variety of lady beetles, mites, and parasitic wasps, which feed on scale crawlers as well as adults. If rapid or heavy scale infestation becomes intolerable, tree care professionals can provide a number of treatments based on the species, and current life-stage, of the scale. For instance, the application of horticultural oils are effective in controlling scale while conserving beneficial predatory insects. When scale infestation is limited to a few small parts of the tree, the pruning and disposal of infested branches can halt its spread.
Contact your arborist now to schedule treatments to help your trees recover from any damage and set up preventative treatments for next season.