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Tree Wound Paints Latest revision:  March 2023 Paints have been used over the years to try to protect tree wounds from invasion by microorganisms and to promote healing. With a few exceptions, paints are not widely recommended for this use. Trees already ...

Oregon’s Most Unwanted: Invasive Species Reviewed: March 2023 Invasive species are those plants, animals, and microbes not native to a region which, when introduced either accidentally or intentionally, out-compete native species for available resources, ...

Nematodes Reviewed: March 2023 R. Ingham, Nematologist, OSU H.J. Jensen, Nematologist emeritus, OSU The word nematode is derived from Greek words meaning “threadlike.” This, in turn, is partly responsible for our calling this group of invertebrate animals ...

Materials Allowed for Organic Disease Management Reviewed: March 2023 Can I Use This Product on My Organic Farm? Nick Andrews, Small Farms Extension (OSU) 1 1 Reviewed by Brian Baker (Organic Materials Review Institute), John Stalley (Oregon Tilth, Inc.) ...

Disease Diagnosis and Management Reviewed: March 2023 Someone who has a plant problem asks two questions: What is the problem, and how do I correct it? These are hard questions for beginners and experts alike. Diagnosis is the process of determining the c ...

Risk Mitigation Measures for Soil Fumigant Pesticides Reviewed: March 2023 Inga Zasada, Nematologist, USDA-ARS-HRCL, Corvallis, OR Since 2009 there have been significant changes to fumigant product labels, which have resulted in changes to risk mitigation ...

Air Pollution (Ozone) Reviewed: March 2023 Jay W. Pscheidt, Extension Plant Pathology Specialist, OSU There is great interest in air quality all over the Western United States when smoke from forest fires fills valleys during the summer. Most of the smoke ...

Grape (Vitis spp.) Relative Disease Susceptibility and Sensitivity to Sulfur Reviewed: March 2023 Grape (Vitis spp.) Relative Disease Susceptibility and Sensitivity to Sulfur Cultivar Powdery Mildew Botrytis Bunch Rot Eutypa Dieback Crown Gall Sulfur Sens ...

Plant Viruses: Dead or Alive? Reviewed: March 2023 Jay W. Pscheidt, Extension Plant Pathology Specialist, OSU At this writing, most of us are in the midst of stay at-home orders due to the SARS-CoV-2 virus pandemic. The world at large is learning more tha ...

Fungicide Theory of Use and Mode of Action Reviewed: March 2023 J.W. Pscheidt, Extension Plant Pathology Specialist, OSU Fungicides can be classified by chemical group, general mode of action, specific mode of action, or by physical properties once in the ...