Archive for the ‘Canker disease’ Category

Empress Tree (Paulownia)

Empress tree (Paulownia tomentosa) is a fast-growing shade tree, in some years adding 4-5 feet of new growth, eventually to reach heights of 40-50 feet and width of 20-30 feet in less than 20 years.  In the first 3-4 years, juvenile trees develop enormous size leaves. Once trees start producing flowers (adult stage), leaves are […]

Avoid Mulch Volcanos

Ever heard of a “mulch volcano? It is a load of mulch that is piled up around the base of a landscape shrub or tree. A common answer I get from homeowners guilty of this practice is that they see professional landscapers and city maintenance crews doing it. Volcano mulch can also cause tree roots […]

Plant Disease Warning: Phytophthora ramorum

Known as “sudden oak death”, this serious plant disease (Phytophthora ramorum) (Pr) from the West Coast kills oak and other species of trees. It has caused devastating effects on the oak populations in California, Oregon, and Washington, and is also present in Europe. Symptoms include bleeding cankers on the tree’s trunk and dieback of foliage. […]

Act Quickly Against Eastern Filbert Blight

European Hazelnut (Corylus avellana) is highly prized both for its edible nuts and as a landscape shrub/small tree. Unfortunately, it is susceptible to eastern filbert blight (EFB). American hazelnut (C. americana) is relatively resistant. EFB is a lethal disease as it may kill a large shrub in 4-5 years. The fungus was discovered in the Pacific […]