Fungus Fact Friday

Tagged: tree

fungal interactions with trees

1

Fungus Fact

#019: Apiosporina morbosa, Black Knot

And now for something completely different: how to recognize different types of trees from quite a long way away.*  Black Cherry (Prunus serotina) is the easiest tree in eastern North America to identify, thanks to the fungus Apiosporina morbosa, commonly known as Black Knot.  Most Black Cherry trees are infected with A. morbosa, which causes dark swellings on branches and trunks.  Older tree trunks are often marred by large swellings caused by A. morbosa that are up to twice the size of the trunk.  These “knots” are easy to spot from a distance (especially in winter), so take advantage of this and amaze your friends by pointing out Black Cherry trees without relying on bark, leaves, or other details!  On twigs and smaller branches, Black Knot makes the branches lumpy and thickened in places, looking remarkably like “dried cat poop on a stick” (thank Michael Kuo for that apt analogy).

Elm Bark Beetle galleries 0

Fungus Fact

#228: Dutch Elm Disease

Elm trees were once the defining tree of American life, widely planted in cities, suburbs, and farms.  This changed beginning in the early 1900’s when Dutch Elm Disease arrived on the continent.  Caused by the fungi Ophiostoma ulmi and O. novo-ulmi, Dutch Elm Disease blocks off the water transportation tissues in elm trees, leading to wilting and death.  The fungus moves between trees by using elm bark beetles as vectors and by growing from tree to tree, making it a difficult pathogen to control.  The best way to manage Dutch Elm Disease today is by planting resistant cultivars – fortunately, there are many resistant options available.

Fungi in the News Image 0

News Update

2018 Fall and Winter Fungal News Update

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of news stories that have taught me something about fungi from September through December 2018. Read each summary to learn about: zombie ants, mushroom poisonings, White Nose Syndrome, Bananas, and more.

cryphonectria parasitica on wood 1

Fungus Fact

#222: Cryphonectria parasitica, Chestnut Blight

The American Chestnut Tree, Castanea dentata, was once one of the dominant trees in eastern North American forests. It rivalled oak trees in terms of size and abundance. The trees were also highly valued for their rot-resistant wood and edible seeds, making it one of the most economically important trees in eastern North America. So, if the trees were so common and so important, where are they today? The downfall of the American Chestnut began in New York in 1904, when a disease called Chestnut Blight suddenly appeared and swept across the continent. By 1950, the disease had infected and killed almost every American Chestnut. Chestnut Blight is caused by the Asian fungus Cryphonectria parasitica, which grows in the outer wood of the tree and essentially chokes trees to death. The aggressive pathogen has doomed the American Chestnut to extinction, unless humans can come up with a solution.

Fungi in the News Image 0

News Update

2018 Summer Fungal News Update

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of news stories that have taught me something about fungi from mid-May through Early September 2018. Read each summary to learn about: zombie ants, mushroom poisonings, White Nose Syndrome, Bananas, and more.

Aleurodiscus oakesii 0

Fungus Fact

#020: Aleurodiscus oakesii, Smooth Patch Disease

Aleurodiscus oakesii is an unusual mushroom that grows on living trees but isn’t considered a parasite. The fungus decomposes the outer layer of hardwood tree bark. This doesn’t harm the bark but does cause smooth patches (thus the name “Smooth Patch Disease”). The mushrooms themselves appear occasionally inside these smooth patches. Each mushroom is a small tan roughly circular crust fungus, so some other common names for the fungus include: “Oak Parchment,” “Hop Hornbeam Disc,” and “Oake’s Crust.” These nondescript mushrooms are easier to identify by their ecology than morphology.  Additionally, you can always see the smooth patches, but the mushrooms are more elusive.  Despite regularly finding smooth patches, it took me four years to find the actual mushrooms.

Fungi in the News Image 0

News Update

Spring 2018 Fungal News Update

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of news stories that have taught me something about fungi from mid-February through mid-May 2018. Read each summary to learn about: gut fungi, ambrosia beetles, gravity detection, prehistoric mushroom use, diseases of toes, ants, frogs, bats, and ohia trees, and more.

Phellinus robiniae 3

Fungus Fact

#081: Phellinus robiniae, the Cracked Cap Polypore

Phellinus robiniae, commonly known as the “Cracked Cap Polypore,” is a woody bracket fungus that is most easily identified by its habitat. This fungus grows almost exclusively on locust trees. In fact, the fungus is such a common pathogen of locusts that nearly every Black Locust tree has at least one P. robiniae mushroom on it. The mushroom is also distinguished by its furrowed cap – which gives the fungus its common name – and its dull brown pore surface.

Cedar-Apple Rust telial horns 8

Fungus Fact

#087: Gymnosporangium juniperi-virginianae, Cedar-Apple Rust

Gymnosporangium juniperi-virginianae is a rust fungus known as Cedar-Apple Rust (sometimes abbreviated to CAR) that causes disease in Eastern Red Cedar and in apple trees. This fungus is unique among rusts because it produces large fruiting bodies. On cedar trees, the fruiting bodies resemble lumpy brown golf balls with long gelatinous orange tentacles bursting out of them. On apple trees, the disease causes more damage but produces only orangish spots. The complex life cycle of Cedar-Apple Rust means the fungus is easy to control, although these control methods resulted in a legal case that was argued before the Supreme Court of the United States!

Fungi in the News Image 0

News Update

2017 Fall News Update

Fungi appear in the news with surprising frequency. However, many of those stories do not provide any new information. Below is a summary of what we’ve learned about fungi from August through October 2017. Read below to learn about: ballistospory, chromosome evolution, fighting fungal pathogens (in humans, bats, and bananas), psilocybin, oil-eating fungi, and more! Visit the associated links to get the full story.