Silver Leaf

What is silver leaf?   Silver leaf is a fungal disease that affects a wide range of deciduous trees.  The disease has its biggest impact in fruit trees such as apple, pear and cherry, but can also affect ornamental trees such as willow, poplar, maple, oak, and elm.  Silver leaf has traditionally been considered a disease […]

Powdery Scab

What is powdery scab?  Powdery scab is a potentially serious disease of potatoes that occurs worldwide in regions where potatoes are grown, including Wisconsin.  Although powdery scab primarily causes cosmetic, if unsightly, skin blemishes of potato tubers, the pathogen that causes the disease can transmit another, more serious potato pathogen, Potato mop-top virus (PMTV).  PMTV was first […]

Red Star Rust

Red star rust (also known as Japanese apple rust or lipstick rust) is a type of Gymnosporangium rust. This plant disease is particularly concerning because of its potential negative impact in commercial apple production. 

Tizón Tardío (Late Blight)

El tizón tardío es una enfermedad destructiva de los tomates y de las papas que puede matar a las plantas maduras y causar que los frutos del tomate y los tubérculos de la papa no sean comestibles. Esta enfermedad también afecta, aunque típicamente en menor grado, a las berengenas y a los pimientos así como a malezas relacionadas como la hierba mora.

Asters, Symphyotrichum spp.

Asters are herbaceous perennial plants bloom late in the year, with daisy-like flowers in shades of lavender, blue, pink, purple and white.

Tree Species Recommended for Fall Planting

These are a compilation of tree species recommended for fall planting/waiting until spring in various Extension resources. Some species appear on both lists. (Last updated 8/9/2024) Trees Suggested for Fall Planting: (September through early October, or weather permitting) Shrubs It’s Better to Wait: Trees That May Do Better with a Spring Planting Shrubs ▶ Watch: Planning […]

Elm Zigzag Sawfly

The elm zigzag sawfly is an invasive sawfly that attacks elm trees. Populations were detected in Wisconsin for the first time in July 2024 and were quickly found in several counties across the state. In many cases, damage may be minor, but this invasive pest does have the potential to cause significant defoliation of elm trees.

5 Steps to Plant a Tree

Interested in planting a tree on your property? Take a look at this tree planting article to learn best practices.

Fascinating Fasciation

Every once in a while the normal growth pattern of a plant goes awry, producing an interesting “mistake” that can be attractive and ornamental, or ugly, bizarre, or humorous. This physiological disorder, called fasciation, can occur in almost any plant part, but is most noticeable in the stems or inflorescences. In a normal plant, growth […]

Blister Canker

What is blister canker? Blister canker (also known as nailhead canker) is a potentially lethal disease that primarily affects apple and crabapple trees.  Other trees and shrubs grown in Wisconsin that can be affected by the disease include American elm, honey locust, hornbeam, magnolia, mountain-ash (rowan), oak, pear, and serviceberry. What does blister canker look […]

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