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Cedar, Western Red (Thuja plicata)-Pencil Rot (Brown Pocket Rot) See: Fir, Douglas and True- Stem Decays (Heart Rots) Cause Stem decay, when found in western red cedar, is usually caused by Postia sericiomollis, a fungus. Old age and stem wounding increas ...

Cedar, Western Red (Thuja plicata)-Yellow Root Rot Cause Perreniporia subacida, a fungus, causes yellow root rot of several conifer species in Oregon and Washington. It is usually found on suppressed or weakened trees. It is rarely seen in vigorous trees. ...

Cherry (Prunus spp.)-Viruses See: Cherry (Prunus spp.)- Cherry Mottle Leaf Cherry (Prunus spp.)- Eola Rasp Leaf (Yellow Bud Mosaic) Cherry (Prunus spp.)- Little Cherry Cherry (Prunus spp.)- Necrotic Rusty Mottle (Lambert Mottle) and Rusty Mottle Cherry (P ...

Sage (Salvia sp.)-Botrytis Blight See: Greenhouse Plants, Ornamental- Gray Mold Cause The fungus Botrytis cinerea is an opportunistic pathogen that easily invades weak, damaged, or senescent tissue such as cotyledons, young stems, and young leaves. Spores ...

Sage (Salvia sp.)-Downy Mildew Cause Peronospora sp., a fungus-like organism. Has not been reported in the Pacific Northwest but has been found in Washington. Favored by high moisture and crowded plant conditions. Symptoms Yellow spots with either diffuse ...

Sage (Salvia sp.)-Impatiens Necrotic Spot See: Greenhouse Plants, Ornamental- Impatiens Necrotic Spot ...

St. Johnswort Go to: Hypericum (St. Johnswort) ...

Saintpaulia Go to: African Violet (Saintpaulia spp.) ...

Salal (Gaultheria shallon)-Leaf Spots See: Tanoak (Notholithocarpus densiflorus)- Sudden Oak Death Cause Many fungi are reported including Dasyschypha sp., Phyllosticta pyrolae, and Pestalopezia sp. The OSU Plant Clinic has identified Phyllosticta sp. mos ...

Salal (Gaultheria shallon)-Root Rot Cause Phytophthora cinnamomi, a water-mold, fungus-like microorganism. The disease is favored in potted plants on plastic sheets, which hold water around the pots. The disease can spread when the sheets are used under o ...