Oak: Anthracnose categories: Oak Oak Diseases Ornamental trees Ornamentals revision date: 2022-11-25 12:33 Biology Oak anthracnose is a fungal disease of leaves and twigs of many species of oak. Typical symptoms include the presence of small to large brown lesions on the leaves, usually along the midrib or main veins. Half or more of a […]
Oak: Armillaria root rot categories: Oak Oak Diseases Ornamental trees Ornamentals revision date: 2022-11-25 12:24 White fungal mat of Armillaria root rot infecting trunkPhoto by: C.R. Foss Biology Armillaria root rot is a fungal disease often found in newly cleared soils or soils which have been flooded. Above-ground symptoms typically include production of smaller-than-normal leaves, […]
Oak: Leaf scorch categories: Oak Oak Diseases Ornamental trees Ornamentals revision date: 2022-11-25 12:20 Oak leaf with leaf scorch symptomsPhoto by: B.M. Johnson Biology Leaf scorch has many possible causes. Plants that are under stress (such as from drought or heat) may not provide sufficient water to leaves, causing the edges to turn bronze, then […]
Oak: Mistletoe categories: Oak Oak Diseases Ornamental trees Ornamentals revision date: 2022-11-25 12:16 Oak mistletoe (a true mistletoe)Photo by: J.W. Pscheidt Biology Mistletoe is a parasitic plant which grows on the branches of a host tree. True mistletoe, found on oaks and a few other hardwood species, does not grow on conifers. It is spread […]
Oak: Sudden oak death categories: Oak Oak Diseases Ornamental trees Ornamentals revision date: 2022-11-25 12:00 P. ramorum symptoms on tanoak leavesPhoto by: M. Elliott Biology Sudden oak death (SOD) is the common name for a disease of oaks (Quercus spp.) and tanoak (Lithocarpus densiflorus) caused by Phytophthora ramorum, a previously unknown and exotic plant pathogen. […]