Death cap mushrooms are highly toxic, but they have many edible lookalikes. If you enjoy hunting for and eating wild mushrooms, you’re going to want to know how to avoid death caps. So you may be wondering, where do death cap mushrooms grow? What kind of environment do they prefer, how do they reproduce, and how did they get to North America in the first place!
Keep reading! In this article, we’ll discuss the answers to all of these questions.
What You'll Learn Today
What Do Death Cap Mushrooms Grow On?
Death caps grow from moist, shaded ground near trees and tree roots. They can be found on every continent except South America and Antarctica.
Sometimes they will continue to grow from leftover tree roots even if the tree is no longer there.
The visible parts of death cap mushrooms don’t grow directly on the trees or their roots, they grow from the soil. That said, they need the tree in order to thrive.
Death caps have a symbiotic relationship with certain species of trees, meaning that both the trees and the mushrooms benefit and complement each other. According to Harvard University, the fungus draws nitrogen from the soil and “feeds” it to the tree, which in turn provides carbon to the fungus.
This particular type of symbiotic relationship is called a mycorrhizal relationship or simply mutualism. These terms are used to refer to a mutually beneficial relationship between trees and mushrooms.
Death caps can form this mycorrhizal relationship with a number of different tree species, but they seem to prefer deciduous hardwoods like oak and beech. In some areas, they have adapted to grow with certain evergreens such as pine.
How Do Death Cap Mushrooms Reproduce?
Like most mushrooms, death caps can reproduce in two different ways: by spreading asexually through the soil, and by releasing spores from their gills.
The visible mushrooms are only temporary expressions of the fungus, which remains in the soil year-round. This fungus moves and spreads by sending out tendrils, like thread-sized roots, through the soil.
Moving this way, the fungus can spread to nearby trees and produce new patches of mushrooms each season.
During the fall and winter, when the mushrooms sprout, they grow and mature until they produce spores. These spores are a bit like tiny seeds, and each mushroom produces hundreds and thousands of them.
The spores are produced in the gills underneath the mushroom caps. When they are mature, each mushroom will release its spores, which blow in the wind and can travel great distances.
Death caps appear to reproduce more readily through releasing spores than through subsoil spreading. But regardless of the method, these poisonous mushrooms spread readily and are highly invasive.
Once the death cap has been introduced in an area, it’s very hard to get rid of. It expands outward from this central location and keeps spreading as long as it finds the proper conditions for growing.
What’s more, the mushrooms seem to be somewhat adaptable to a variety of conditions. Though they prefer growing near certain deciduous trees, they are continuously being found with other species of trees besides oak, beech, and pine.
Death caps were introduced in North America and Australia by mistake and are now spreading rapidly–like weeds.
How Did Death Cap Mushrooms Get to North America?
Scientists believe that death caps were first brought to California in the 1930s. The fungus seems to have been attached to the roots of some ornamental trees that were imported from Europe.
In the following decades, they spread like wildfire throughout California, cropping up in various localities where they are now a common sight. The San Francisco Bay area has one of the worst infestations in the state.
But death caps are not limited to California. They have since shown up in other states as well.
They are most common throughout the west coast, where they seem to prefer growing near the coastal live oak. In Canada, they were first discovered in British Columbia in 1997.
They have also spread to eastern states as well. In the east, they most commonly grow near pine trees.
Considering their adaptable and invasive qualities, death caps will probably continue to spread throughout the United States and Canada. If you forage wild mushrooms, no matter where you’re located, it’s a good idea to familiarize yourself with this highly toxic mushroom so you don’t end up accidentally harvesting and eating it.
For more information on how to tell apart edible and poisonous mushrooms in general, check out the following video.
Death cap mushrooms grow near many varieties of trees throughout the world. Though native to Europe, it now grows wild throughout much of North America, Australia, Asia, and Africa.
Death caps spread easily and are hard to get rid of. They may continue to grow near dead roots even after a tree has been removed.