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Common as muck! The Common Earthball

It was only a couple of weeks ago whilst looking for the first signs of all the different Russulas that my attention was drawn away every two minutes only to find these little blighters. They were everywhere…

Round EarthballsWith a well deserved name, the Common Earthball (Scleroderma citrinum) is very numerous during the summer and autumn months, in and around damp woodland in rich peaty soil or moss. It is often in small scattered groups of 2 to 4 or so together, sitting there like discarded old potatoes! It is a mycorrhizal species and shares this special relationship with deciduous trees, especially oak, beech and birch.

‘Potato like’ is a good analogy I think. They can grow up to 10cm in diametre and have an irregular ovoid like shape. The colour can be dirty yellow to ochre brown with rough scales all over the surface.

The difference ends once you cut the fungus in half. In an immature specimen you will find a solid blackish spore mass (the gleba) with a subtle marbled effect. The smell is quite a strong metallic odour which I find very unpleasant. At maturity this spore mass will turn into fine power and the outer surface will rot and split wide open in a random spot, unlike the puffball trait of opening at the apex, to release it’s spores.

There are several lookalike Earthballs out there, such as the Scaly Earthball and Leopard Earthball. These have some key differences, such as the surface texture or pattern. But there is quicker way to identify between these similar fungi. Unlike these examples, the Common Earthball has no stem at all, merely mycelial white cottony cords attached to the soil and it’s outer skin is very thick in comparison (from 2 – 5mm). Simply squeeze a Scaly Earthball and you’ll easily misshape the whole thing, the Common Earthball on the other hand won’t budge. Nice and sturdy.

Anyway, it goes without saying that this Earthball along with the rest are quite inedible, and the Common Earthball has been classed as poisonous in the past (which I agree with), but one comment from Jo (below) mentioned they are eaten regularly in the Philippines where she is from. However Gareth and Deborah from UK (another comment below) had a bad experience with sickness. I don’t like the smell (or the looks of them) at all, so I’ll just be avoiding it in future – like a bad potato.

Common Puffball pictures

QUICK ID TABLE: COMMON EARTHBALL Scleroderma citrinum

FRUITING BODY

2-10cm in diametre. Almost Spherical / Irregular potato shape. Dirty yellow to ochre brown with coarse scales. Outer wall thick.

STEM

No stem. Attached to soil by fine mycelial threads.

GLEBA

Purple/Black with white veins / markings. Turns to powder when mature.

HABITAT / SEASON

Rich soil in and around deciduous woodland. Summer & autumn. Widespread & very common.

EDIBILITY

Inedible.

The PUFFBALLS/EARTHBALLS & ALLIES (Stomach fungi): Characteristics to look out for:

• Main fruting body is ball shaped, irregular or pedicel shaped. Broken or split at maturity to release spores
• Interior of fruiting body full of gleba (spores); solid when young, as a powder at maturity.
• Often small or no visible stem.

Update: 3rd October 2012. Two Fungi as One!

If you’re lucky, you may get see the Parasitic Bolete (Pseudoboletus parasiticus) that exclusively grows on older bodies of Common Earthballs and therefore easy to identify. The matt textured, olive/brown/yellow cap grows up to 4cm across. Sometimes there are several feeding off the one earthball.

They’re pretty widespread and occasional, and in-fact edible (some say not) but definitely not poisonous. The picture below was kindly sent to me from blog follower Chris Thornley. It was found in woodland near Sandringham. After rain, the cap seems to have a tacky texture. Thanks for the pic Chris.

Pseudoboletus parasiticus

© Chris Thornley 2012 – Parasitic Bolete (Pseudoboletus parasiticus)