Diseases & Disorders
All Diseases & Disorders Content
Phylloxera: A Grape Pest
Some grape growers may notice that some of their shoots have bumpy growths on the bottom of new leaves. These bumps are galls caused by the grape phylloxera, an aphid-like insect.
Swine Respiratory Health: Detecting Multiple Viruses
Over the past decade, surveillance and diagnosis of respiratory agents have been revolutionized by the use of non-invasive techniques such as oral fluids sampling.
West Nile in South Dakota: Expect Cases Into Early Fall
While it’s true that in South Dakota most West Nile Virus cases occur during August, new human infections are detected well into September in most years.
Dairy Calf Respiratory Disease: Treatment in the Aftermath of Cold Weather
Cold weather is not just hard on the people taking care of animals, it can be tough on the animals themselves. Consider respiratory disease (pneumonia) in dairy calves.
Sawyer Beetles and Pine Wilt Disease
A sample came in from a recently felled Scotch pine tree down in Southeastern South Dakota. The hole and sawdust is due to a sawyer beetle that had infested the tree.
Fall Yard and Garden Cleanup
Before the snow falls, a few tasks can help make for a healthier yard and garden next year.
Ash Tree Issues
Ash flower galls are appearing on the twigs of ash throughout the state. The brown to black “balls” hang in clusters beneath the branch shoots. The galls are due to the feeding activity of the ash flower gall mite (Eriophyes fraxiniflora) and this mite only feeds on the male flowers of ash.
Aphids On Trees
Aphids are appearing on many trees at this time of year and their activity is generally noticed by the abundance of honeydew they excrete on the lower leaves and any plants or objects beneath the tree.
Cottonwood Galls
Just about every year I receive samples of fallen cottonwood leaves with a “bump” at the base and the first one for this year was from Winner. This is the cottonwood petiole gall formed by the feed activity of a very small green aphid.
How to Prevent Iron Deficiency in Spring Greenhouse Plants
At this time in the growing season, Iron (Fe) deficiency symptoms are appearing among bedding plants and other spring greenhouse plants. The main symptom of Iron (Fe) deficiency is Chlorosis or yellowing, usually starting at the shoot tip and newly developed leaves.