With spring finally arriving in Wisconsin, trees and shrubs will be exiting their state of hibernation and beginning to show their liveliness. During this transitional period, vulnerability to fungal diseases is much higher. With the change in season comes the perfect time to provide the necessary nutrients needed to fight off and prevent fungal diseases from plaguing your trees. Perhaps the most common fungal diseases throughout Southeastern Wisconsin is Apple Scabbing and Diplodia Tip Blight.
Apple Scab Treatment
Found on apple and crabapple trees, apple scab (also known as Venturia inaequalis) is a fungal disease that targets both the fruit and their leaves. Overwintering occurs mainly in fallen leaves and the soil that surrounds them. Conditions that promote the development of apple scabbing includes wet, cool weather that occurs inconveniently during spring and early summer. Temperatures ranging between 55 and 75 degrees F mixed with fungal spores carried by wind and rain leave newly opening fruits vulnerable to infection.
Symptoms for Apple Scabbing on leaves includes discolored yellow and/or olive-green spots on the surfaces of leaves. Depending on the level of infection, leaves can also pucker and fall earlier in summer. Symptoms on fruit includes tan, sunken spores along the surface. Overtime, they become brown in color and become more susceptible to additional threats.
Diplodia Tip Blight Treatment
Another fungal disease common during spring is tip blighting (also known as Sphaeropsis). Common in stressed conifers such as pines with needles in bunches, the disease is known to target trees above 15 years of age. Severe cases almost exclusively exist in trees that are older than 30 years. The culprit behind the disease is Diplodia pinea. This fungus overwinters in fungal fruiting bodies found in shoots, bark and seed cones when they’re infected. During wet, cool weather experienced during spring and early summer, tiny spores known as conidia erupt from the pycnidia, attacking the shoots (also referred to as candles).
Diplodia destroys needles near the tips of branches. Beginning on the lower half of a pine and slowly moving upwards, the most common symptom are needles becoming stunted, changing to a yellowish color and eventually becoming tannish-brown in color. Near the base of the needle, black fungal fruiting bodies (pycnidia) can be spotted. As lateral shoots are killed, entire branches can be taken out.
Spring Fungal Disease Treatments from Wachtel
Staying ahead of spring-time fungal diseases will keep your pines and apple trees protected, enabling them for healthy growth. Our certified arborists not only understand how these fungal diseases develop and attack but also know exactly how to implement the proper treatment to prevent them. Whether you’re noticing signs of apple scabbing or diplodia tip blighting or not, scheduling an assessment and/or treatment now will ensure your trees bloom fully for summer.