Leyland cypress branches turn brown because of an infiltration of three types of fungi: seiridium, bought, and cercospora. These three fungi enter into the tree during the summer months when the heat enlarges the tree’s stomata (pores on the leaf) and allow entrance of the fungi.Click to see full answer. Keeping this in view, what causes Leyland cypress trees to die?Although Leyland cypress shrubs are affected by a variety of root rot problems, the rot disease that may lead to browning is annosus root rot. This fungal disease most often affects landscape trees by invading newly cut stumps that are near your Leyland cypress trees.Likewise, what is wrong with my Leyland cypress? Leyland cypress is considered relatively pest-free. However, because of its relatively shallow root system, and because they are often planted too close together and in poorly drained soils, Leyland cypress is prone to root rot and several damaging canker diseases, especially during periods of prolonged drought. Accordingly, how do you know if a cypress tree is dying? How to Know If a Cypress Is Dead Examine the Cypress tree’s bark. If the bark has a brittle texture and is falling off in large chunks, the Cypress tree might be dead. Look at the tree’s limbs. Break off one of the branches at the bottom of the tree. Examine the needles of the Cypress Tree. Examine the tree trunk for large cracks. What is the life expectancy of a Leyland Cypress tree? 20 to 25 years
