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Rose Cultivar Resistance Reviewed: March 2023 Rose (Rosa spp.) — Cultivar Resistance The fungal diseases rust, powdery mildew, and black spot are common in Pacific Northwest rose gardens. Cultivars in this table were grown and tested at the Portland, OR I ...

Tomato (Solanum lycopersicum)-Varietal Resistance Reviewed: March 2023 Tomato (Solanum lycopersicum) — Varietal Resistance Varieties listed are resistant to Verticillium wilt, Fusarium wilt, root-knot nematode, and/or Tobacco mosaic virus. Variety Maturit ...

Tomato (Solanum lycopersicum)-Tomato Varietal Resistance to Fusarium Wilt and/or Crown and Root Rot Reviewed: March 2023 Tomato (Solanum lycopersicum) — Tomato Varietal Resistance to Fusarium Wilt and/or Crown and Root Rot. Fusarium wilt is caused by race ...

Parasitic Plants of Oregon Reviewed: March 2023 Jay W. Pscheidt, Extension Plant Pathology Specialist, OSU Richard Halse, Herbarium Curator, OSU Kathy Merrifield, Nematologist, OSU (Update to Mistletoe section by Dave Shaw, Extension Forest Health Special ...

Tree Decline Reviewed: March 2023 M. Putnam, Director of the Oregon State University Plant Clinic Landscape tree samples often come into the OSU Plant Clinic with the complaint of a thinning canopy and premature leaf drop. Usually, samples do not have vis ...

Thatch in Home Lawns Reviewed: March 2023 M. Putnam, Diagnostic Plant Pathologist, OSU T. Cook, Professor emeritus, Horticulture, OSU What Is Thatch? Thatch is a tangle of dead and living plant parts (stems, crowns, stolons, rhizomes, and roots) that accu ...

Algae, Lichens, and Mosses on Plants Reviewed: March 2023 A.D. Davison and R.S. Byther, Professors emeriti of Plant Pathology, WSU Algae, lichens, and mosses grow profusely on trunks, limbs, and twigs of many trees and shrubs. The cool, cloudy, wet weathe ...

Winter Injury of Landscape Plants in the Pacific Northwest Reviewed: March 2023 R. Maleike, Extension Horticulturist, WSU Puyallup Research and Extension Center M. Ophardt, WSU Area Extension Agent, Benton-Franklin Counties S. Collman, WSU County Extensio ...

Plant Nutrition Diagnosis Reviewed: March 2023 James Altland, former Extension Horticulturalist, OSU The only way to accurately diagnose a nutritional problem of plants is to conduct a soil test and tissue analysis at the same time. This identifies which ...

Key to Nutrient Deficiencies in Vegetable Crops Reviewed: March 2023 Deficiencies producing distinct color changes in foliage. 1. Symptoms first apparent in young leaves. Element Deficient a. New leaves develop light-yellow color, first between veins. Lat ...