Tobacco Mosaic

Tobacco mosaic causing a blotchy light and dark coloring (mosaic) of tobacco leaves. Tobacco mosaic causing a blotchy light and dark coloring (mosaic) of tobacco leaves.

Fungus Gnats on Houseplants

Fungus gnats (Family Sciaridae) are insects commonly associated with overwatered houseplants. They can become a nuisance when they are present in large numbers and fly around inside a home. In most situations, fungus gnats are a cosmetic problem. However, on occasion, fungus gnat larvae can cause plant damage.

Powdery Mildew – Herbaceous Ornamental

Powdery Mildew – Herbaceous Ornamental Authors: Brian Hudelson, UW-Madison Plant Pathology Last Revised: 02/18/2010 X-number: XHT1005c What is powdery mildew? Powdery mildew is a disease that occurs on the above-ground parts (especially the leaves) of many herbaceous ornamental plants, as well as deciduous trees and shrubs, indoor houseplants, and many agricultural crops. Conifers are not […]

Phenology

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  5/17/2012 Item number:  XHT1085 The word phenology is derived from the Greek word phaino meaning “to show” or “to appear”.  Phenology is a branch of science that studies the relationships between periodic biological events—usually the life cycles of plants and animals—and environmental changes.  Natural events such as […]

Degree Day Calculation

Karen Delahaut, UW-Madison Fresh Market Vegetable Program Revised:  8/6/2012 Item number:  XHT1086 Indicator plants are not always suitable for the timing of pest management practices.  You may not have the critical indicator plant  nearby to time local activities, or there may not be a good indicator plant for a particular pest’s crucial life stage.  Another […]

Hot-Water Seed Treatment for Disease Management

Growing vegetables from seed is a common practice for many home gardeners. Unfortunately, vegetable seed can sometimes be contaminated with disease-causing organisms, particularly disease-causing bacteria. Learn how to use hot water treatment to reduce pathogens that may be carried on seeds in this guide.

Cucumber Mosaic

Cucumber mosaic is a viral disease of worldwide distribution that affects over 1200 plant species. Hosts include a wide range of fruits, vegetables, herbaceous and woody ornamentals, and weeds. This factsheet covers identification and ways to prevent this incurable disease.

Gladiolus Disorder: Virus Complex and Aster Yellows

Viruses can destroy the value of a gladiolus crop. Serious infections have been observed throughout Wisconsin in some years. While Aster Yellows is common, it usually infects just a few gladioli scattered in plantings. This fact sheet covers the symptoms, causes, and means of control of viral and Aster Yellows infection.

Hosta Virus X

Hosta virus X (HVX) is a viral disease that causes serious problems on many hosta cultivars, causing nursery owners and gardeners in the United States to voluntarily destroy large numbers of hosta to help prevent the spread. This fact sheet describes the symptoms and management of this virus.

Root-Knot Nematode

Root-knot nematodes (Meloidogyne spp.) are small, soilborne, worm-like organisms that infect many agricultural and horticultural plants. This publication describes the symptoms, management and control of root-knot nematodes in Wisconsin.

Foliar Nematodes

Foliar nematodes are microscopic worm-like organisms in the genus Aphelenchoides. They live in and on the leaves (and other above-ground plants parts) of over 450 plant species in more than 75 plant families. They are commonly found on hostas, but can affect other herbaceous ornamentals. Learn what to look for and how to manage foliar nematodes in this factsheet.

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