Photo of the Week
Patton's Silver Splendor White Pine, a selection we recently released at the University of Minnesota that has resitance to white pine blister rust. The tree has a silvery sheen due to increased wax on needle surfaces. The tree was originally selected many decades ago by Robert Patton and others at the University of Wisconsin. Screening and testing at the University of Minnesota has shown this selection to have excellent resistance. The original tree is from Duluth, Minnesota.
Aecia of the introduced pathogen, white pine blister rust, showing the characterisitc "blisters" that are produced in the spring on white pine. Aeciospores infect Ribes.
The University of Minnesota St Paul Campus (1970's) before Dutch elm disease started to take its toll. This picture shows where the buses stop outside of the student center.
An unusual looking canker on an ash tree found by a student who previously took this class. What canker causing fungus do you think is responsible?
This home owner asks "Is my tree going to die?" Maple anthracnose can cause problems in the spring and early summer. Will this tree die?
Spring infection of oak with oak anthracnose can mimic the symptoms of oak wilt. However, there are ways to differentiate oak wilt from oak anthracnose.
Tree wrapped with heavy twine to prevent winter sunscald. This is a method used in China. Apparently it is effective but very labor intensive to put on and take off each year.
Maple leaves with a problem. How can you determine if this is caused by an abiotic or biotic agent?
Keeping forest and urban landscape trees healthy requires knowledge of tree diseases. This class will provide you with important information you can use in the future.