What Does Mycelium Look Like?

All mycelium looks like long strands of hairs (often white) which grow from a central point expanding outwards (a bit like a tiny root system of a plant). 

Underneath a microscope, mycelium looks like a dense network of tiny white filaments. 

These filaments are called hyphae and they are what make up the mycelium structure. 

Hyphae are important for the mycelium to be able to grow and spread as they help to transport water and nutrients throughout the mycelium network. 

Many mushroom mycelium strains develop unique characteristics when grown on agar or grain. 

As a result it can be possible to differentiate some strains of mycelium just by looking at its characteristics.

Below will go over some of the most common mushroom strains and what their mycelium looks like through various stages of growth, on different growing media.

What Does King Oyster Mycelium Look Like?

King Oyster mushroom mycelium looks wispy and fluffy, the mycelium is white/greyish coloured and starts thin and then thickens up. When fully colonized, the mycelium will have a thin 'cotton wool' like appearance.

Once fully colonized it is still possible to see the agar underneath the king oyster mycelium.

In the book “growing gourmet and medicinal mushrooms' ' Paul Stamets describes King Oyster mycelium as ‘cottony with age’ which is probably the best description of it as it matures.

King Oyster Mushroom On Agar.

Day 3 – Early after innoculation the fluffs up slightly.

Day 3 – The mycelium grows outward with thin hairs.

Day 7 – King Oyster mycelium expands further.

Full Colonization.

King Oyster Mycelium On Grain.

King Oyster Mycelium looks slightly gray and grows out in rhizomorphic patterns as show in the picture below

What Does Blue Oyster Mycelium Look like?

Blue oyster mycelium is described as being 'woolly' or 'cottony'. The mycelium is bright white and is quite dense and compact. It grows very aggressively even occupying space inside an agar plate or grain jar which doesn't contain nutrients.

Blue oyster mycelium is a fast colonizer, forming a dense cotton-wool-like appearance, blue oyster mycelium will grow so densely you will be unable to see the agar beneath it once fully colonized.

Blue Oyster Mushroom On Agar.

Blue Oyster Mycelium On Grain.

Blue Oyster Mycelium grows aggressively in grain jars creating a bright white jar and even the white air gap in the top of the jar will become colonized and filled with mycelium.

What Does Lion’s Mane Mycelium Look Like?

Lion’s mane mycelium looks extremely thin, wispy and grey in colour early in colonization. It can be difficult to see growth the first time you grow it and it can often get mistaken for cobweb mold.

Sometimes it requires a light to pick up any growth especially early on in large jars.

The mycelium begins to thicken up just before the fruiting stage where it will turn from grey to bright white. 

When the center has thickened up it can make some quite elaborate 3D shapes on agar which can resemble coral. 

More often than not ariel growth begins instead of radial growth and you will see fruiting inside the plate.

Lions Mane Mushroom On Agar.

Often Lion's mane will not appear to reach the outer edges of the plate on agar, this is probably because the mycelium is too thin to see at the edges. 

Lions Mane Mycelium On Grain.

The first week after inoculating grain with Lions mane you probably won't see much unless you use a light.

Inspect your jar for greyish thin lines which are developing uniformly. Mycelium will often stretch about 2mm above your grain and not fill any spaces at the top of the jar.

Cobweb Mold Vs Mycelium

Here is a picture of cobweb mold on agar. You can see how the mold doesnt grow in a uniform fashion. Alongside this cobwebmold grows extremely fast, it will take over a monotub in a few days which mycelium wont do.