Tuesday, November 21 from noon to 1:00pm Even the healthiest trees harbor fungi and other microorganisms, including both pathogens (which weaken and kill organisms) and saprotrophs (which consume dead tissues). In the era of DNA-based assessments, we are now learning that the diversity of these organisms in trees can be staggering. What we do not yet know, however, is how […]
Foliage diseases my cause conifer needles to turn yellow or brown or drop prematurely. Hardwood leaves may develop yellow, brown, or black spots. These diseases weaken trees by reducing the ability of leaves to produce plant food.
Forest health is affected by insect outbreaks, diseases, invasive species, regeneration, fire ecology, natural disturbance, and many other factors. Not all insects and diseases are bad. Native insects and diseases are a normal part of a healthy forest. An example is the periodic defoliation events from forest tent caterpillars (sometimes called armyworms). Minnesota forests evolved in the presence of these bugs, […]