Indoor Citrus

Even though we can’t grow oranges and grapefruits outdoors in the Midwest, it is possible to keep a citrus tree as a houseplant in a warm, sunny room. Even if your plant never produces fragrant blossoms and brightly colored, ornamental fruit, the shiny, dark green leaves make citrus an attractive container plant. Learn more about the long history of citrus throughout the world and how you can grow your own…

Spotted Lanternfly

Spotted lanternfly (SLF) is an invasive planthopper native to China, India, and Vietnam. It was first detected in the U.S. in Pennsylvania in 2014, and due to its highly invasive nature, it appears to be spreading rapidly. SLF has a large host range and potentially could greatly impact the grape, tree fruit, plant nursery and timber industries in the U.S. Learn about what to watch for with this new pest.

Japanese Beetle

The Japanese beetle, Popillia japonica, is a significant pest of landscape trees and shrubs, vegetable and fruit crops, and turfgrass in the eastern United States. This factsheet describes the lifecycle of this destructive beetle along with management and control options.

Black Knot, Apiosporina morbosa

Unsightly dark-colored lumps on plum trees are not only unattractive, but if there are lots of them, they can disfigure or even kill small trees. These swollen growths are caused by a fungal pathogen that causes the disease known as black knot. To learn more about this disease and how to manage it, read this article…

Fruit and Frost

Because of our climate, Wisconsin always has a risk of spring frosts. Temperatures below 28°F will injure or kill flowers or immature fruit. This factsheet will briefly outline critical temperatures at different stages of flower development, and describe how a gardener might protect against late season frosts.

Watercore of Apple

Author(s):T.R. Roper Watercore of apple is a physiologic disorder. The fruit tissue’s abnormal condition is a response of some apple cultivars to adverse environmental conditions—not to a disease-causing organism. Watercore is more common in warm, arid regions, but it occurs in Wisconsin often enough to concern apple growers. Find out more about this apple disorder […]

Apple Disorder: Sooty Blotch and Flyspeck

Author(s):P.S. McManus, M.F. Heimann Sooty blotch and flyspeck are separate diseases that often occur together on apple and pear fruit during late summer. This fact sheet will help you better understand, identify, and control these diseases. Download Article

Rootstocks for Fruit Trees in Wisconsin

Author(s): Teryl R. Roper To grow fruit that is true to type, fruit trees are propagated by budding or grafting sections of known cultivars (scions) onto special rootstocks. This creates fruit trees composed of two parts: a scion (cultivar) and a rootstock. Many nurseries now offer trees with a choice of several rootstocks. In this […]

Raspberry Disorder: Fire Blight

Author(s): M.F. Heimann, S.N. Jeffers A serious disease of apple and pear trees in the Midwest, fire blight also affects many other members of the rose family, including raspberry. Although still relatively rare on raspberries, this disease has become increasingly common on certain red raspberry cultivars in Wisconsin. Find out hot to spot, prevent, and […]

Plant Growth Regulator Use in Apples

Author(s): Teryl R. Roper Plant growth regulators (PGRs) can be used with some precision for thinning fruit, regulating growth and adjusting harvest periods for apples. These products are absorbed by plant cells, primarily through the leaves and fruit, where they interact with the bio-chemical “machinery” of the plant. They work by mimicking naturally occurring plant […]

Deciduous Tree and Shrub Disorder: Skeletonizing by Rose Chafer

Author(s): R.C. Williamson, C.F. Koval Skeletonizing of the leaves of roses, raspberries, grapes, fruit trees, and many other cultivated trees and shrubs may be caused by the adult rose chafer, Macrodactylus subspinosus (Fabricius). Adult beetles are attracted to flower blossoms, particularly roses and peonies. Damage occurs in June and tends to be most severe in […]

Spotted Wing Drosophila

Christelle Guédot, UW-Madison Entomology Revised: 01/09/2015 Item number: XHT1237 Spotted wing Drosophila (SWD), Drosophila suzukii, is an invasive vinegar fly native to Southeast Asia.  It became established in Hawaii during the 1980’s, and was first discovered in the continental United States in California in 2008.  SWD quickly spread throughout the Pacific Northwest and Canada, and […]

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