Archive for the ‘Leaf retention’ Category

How Drought Affects Our Landscape Trees*

Long term drought can be devastating on landscape and woodland trees. An environmentally stressed tree must expend additional energy to survive. Extremes of drought leads to decreases in trunk diameter and height growth, declining resistance to pests and diseases, less food production via photosynthesis, and in flower and fruit production. Symptoms of drought stress include wilted […]

Leaf Retention In Landscape Trees

              Most deciduous landscape trees drop their leaves sometime in autumn. The physiology of autumn leaf drop is primarily stimulated by changes in photoperiod or shorter daylength. Autumn colors develop and the leaf petioles form an abscission layer. Black gum (Nyssa sylvatica), for example, start to color up in early September. Winter leaf retention by […]