Problems With Leyland Cypress Trees

Some trees in the United States Leyland Cypress (Capressocyperis x leylandii) in the United States The Department of Agriculture can match plant hardiness zones 6 to 9 for the ability to build fast-growing evergreen fences. It defines boundaries, provides privacy and provides windbreaks. Despite all of its characteristics, Leyland is susceptible to cypress diseases and pest problems which can be difficult to control.

Cankers

Cankers of Ceridium (Ceridium spp.) And Bot (Botryosphaeria dothidia) usually attack Leyland. Ceridium canker was discovered in the 1920s on the Monterey Cypress Trace (Capresus macrocarpa) in California. By the 1980s, the disease had spread to Leyland Cypress, a cross between Monterey Cypress and Nutka Falls Cypress (Chamesiperis notcatensis). Since the 1980s, ceridium cancer has spread aggressively on trees across the United States. Cancer occurs when fungal pathogens invade Leyland Cypress through its bark and cause sores on branches and twigs. Many cancers surround a limb, which hinders the transport of nutrients to that organ. The branches die off, leaving brown leaves at the ends. Fungicides are not recommended for the treatment of this disease, and the best prevention is to maintain the maximum health of the tree.

Needle break

Commonly known as Sercospora, or Sercosporidium needle blight, the disease is caused by the pathogenic fungus Pesalora sequoia. The needles near the trunk turn brown on the lower branches. As the disease progresses, the browning of the branches spreads upward and outward. Excessive irrigation, heavy rains, or wet leaves in the shade all contribute to the growth of dew spores and the spread of disease on trees. Clemson Cooperative Extension recommends the use of fungicide sprays to manage needle infestation on small trees, but the height of mature trees restricts the proper use of the fungicide.

Root rot

Root rot, caused by fungi of the Phytophthora species, usually affects young trees in poorly drained areas. These pathogens live in the soil and enter the bush through wounds or tender roots. As the fungus destroys the roots, characteristics of the topsoil include sparse, dwarf or yellow leaves. The disease can cause cancers above or below ground level. Chemical controls are ineffective in eradicating this disease. Infected plants should be removed, but replacement plants are prone to disease caused by residual soil fungi.

Bedbugs and spider mites

The bug Thridopterix ephemeraformis is the larval stage of a moth. Their common name refers to the bags or cases that caterpillars make from pieces of silk and needles and attach to trees. These knitted needles provide camouflage which makes it difficult to locate larval cases. The tips of the needles turn brown due to early loss of food by young caterpillars. A heavy infestation, usually caused by an old bagworm, can destroy a tree in two weeks. The spruce moth (Oligonicus ananguis) leaves the tail strap of the Leyland cypress, which is often mistaken for a spider web. Insects use the web as a defense structure, not to trap their prey. They feed the needles, squeezing the juice through their sharp mouths. Yellow needles are evidence of early pest damage, and brown needles falling from trees indicate heavy infestation. Pesticides are impractical for bagworms and pests because the mature height of Leyland Cypress completely prohibits spraying.