Day 85: At first glance, one might assume that Chondrostereum purpureum (Silver-leaf Fungus) was like any other polypore, but a view of its under-side reveals a significant difference: it's smooth, as opposed to exhibiting the tiny pores characteristic of most shelf fungi. When I first saw it near Rainey Creek, I said in respect to its eventual identification, "This is gonna be either really easy or really hard." Fortunately, it turned out to be the former, so I spent the rest of yesterday evening reading various papers, fascinated by what I found in regard to its pathogenic effects. Chondrostereum is a fungal disease which attacks various hardwoods, specifically those in the genus Prunus (plums, cherries, etc.). It also affects other broadleaved deciduous trees such as maple, oak and willow. For this reason, it is cultivated by the timber industry for application where faster-growing "weed" trees such as Red Alder threaten to shade out cash crops of evergreens. Deliberately infected, the unwanted trees quickly succumb to it, the effects noticeable in the silvering of their leaves (hence the common name, "Silver-leaf"). It also occurs naturally on rotting stumps and logs. Healthy trees tend to be resistant to the disease, so it seldom becomes problematic in a balanced forest ecology, but its effects on stressed trees such as those grown in timber plantations can be devastating.
