What are mycorrhizated trees?

 Esquema de una raiz micorrizada.

View of what happens in the soil between the roots of a tree and the mycelia of a fungus. Mushrooms are the result of the sexual reproduction of the fungus.

Many fungi live associated with forest trees. This plant-fungus association is very common in nature and is known as symbiosis. This symbiosis is established at the level of the fine roots of the plant. The fungus with its filaments –the technical term is hyphae, and the combined hyphae form the mycelium – surround the ends of the finest roots of the tree to form mycorrhizas. This symbiosis favors both living beings, and thus both plant and fungus need this association.

Mycorrhizas of saffron milk cap or red pine mushroom. In this case, the appearance of the root is modified, forming the typical thicker terminations that in the case of the saffron milk cap mushroom have an orange color.


LasThe mycorrhizas are small, fine roots of the plant that have been surrounded by the fungus and are different in appearance from a normal root, presenting a thickening in the form of a match head. As the tree grows, if the ground is propitious for the fungus, the fungus will also grow along with the tree’s roots and the time will come, after a few years, when it will produce mushrooms (saffron milk cap mushrooms, truffles, etc.) depending on the mycorrhizal fungus and the type of tree. Mushrooms or truffles are the fruit of the fungus’ reproduction and carry spores, which are the seeds of the fungus.

The mycorrhizas, in general, aren’t visible to the human eye; training is necessary to identify and observe them, along with technical instruments (microscope, stereoscopic magnifying glass, etc.).

Is there a diference between a fungus and a mushroom?

 Ectomicorrizas en plántula de pino.

We can see in the image the white tangle of filaments of the mycelium that appear out of the mycorrhizas of the tree´s roots: this is the fungus that produces the mushrooms that we collect in the forest.

Fungi are a broad group of living organisms distinct from animals and plants and although they share some similiraties with plants and animals, they form their own so-called «Fungus kingdom». It is believed that more than one million species of fungi exist, but only around 100,000 are know. Fungi can live in different ways, either in the soil decomposing vegetal and animal remains -they’re rightfull called garbage collectors of the world- or associated with plants and fungi is know as symbiosis and is good for both parties. Finally there are also fungi that live at the cost of other living beings; they are called parasites and produce diseases both in animals and plants and can ocasionally cause the death of the organism they feed off of. 

 Diferencias entre setas y hongos.

Visible at the base of the trunk of this saffron milk cap mushroom is the mycelium mixed with soil that was the precursor of the mushroom.

The «body of the fungus» is generally formed by a tangle of filaments (hyphae), all of wich together are called mycelium. Fungi exist in all environs of the Earth. When we are in the forest and lift up the vegetal layer of the soil, it is common to see that braiding of the white filaments that run throughout the subsoil; this is the mycelium of th fungi. Some are associated with trees forming a symbiosis, while others, know as saprophytes, live off decomposing organic material.

When these “mycelia” reproduce, they form what we know as mushrooms. Not all fungi produce mushrooms when they reproduce, this characteristic is usually only found in certain more developed fungi. Mushrooms, in turn, are the bearers of the seeds of the fungi, known as spores. Thus, while the terms fungus and mushroom are frequently used interchangeably, they are different things: mushrooms appear as the result of the sexual reproduction of the fungi and this normally happens when humidity and environmental temperatures are favorable.

What are the trunks that produce mushrooms?

 Troncos para plantar setas en el jardín.

The image shows the whit mycelium on the wood and the mushrooms produced by that mycelium.

There is broad group of fungi that live differently from the way truffles or saffron milk cap mushrooms live. They grow on the wood of dead trees, feeding off the lignin and cellulose provided to them by the wood. These fungi are generally considered saprophytes. The trunks we provide are pieces of recently cut wood that we have inoculated with the mycelium of the fungus. As the fungus grows in the dead wood, the moment will come when, due to itss degree of development and favorable environmental conditions (humidity and temperature), mushrooms will form.

We offer trunks of black poplar, oak, etc. We use one type of wood or another, depending on the type of mushroom we want to produce. In general, most mushrooms work well with black poplar, but for some, such as the shitake, we also use oak wood. These trunks are inoculated (seeded) with the mycelia of the various mushrooms and are delivered to the client after a period of incubation (of the development of the fungus on the wood), in general, between 1 and 3 months. Each species of fungus has a period of incubation before beginning to produce mushrooms; the duration of the incubation stage depends on the type of mushroom, the hardness of the wood, the environmental temperature, etc. These periods can vary from between three months for the most precocious species, up to one year for those that grow more slowly.

The wood we use comes from known sources; the black poplar comes from conveniently exploited riverside plantations that have grown in soil that has been free of chemical additives for at least ten years or more. The oak wood comes operations to thin out of the woodland controlled by forest rangers.

Who predictable is the behavior of mycorrhizated trees in terms of their production?

 Árboles micorrizados con trufa.

In the garden, in the orchard, truffle trees or those of saffron milk cap mushrooms, must first reach a level of growth before they will produce the first mushrooms or truffles. 

Trees in mycorrhizal association with truffles can begin producing between 5 and 10 years after being planted. Once begun, production can last for many years (20-30 years). According to the site, we must make sure which (tree-fungus) pairing is best (not all pairings serve for all sites). Depending on the type of soil, the climate, rainfall, etc., we will decide which is the best pairing.

. You can request our advice by telling us about the characteristics of the site where you want to plant (altitude, type of soil, native trees of the site, etc.). You can visit the section “seedlings mycorrhizated with truffles” of our website (www.cultivosforestales.com) where you will find quite a bit of information on the subject.

 In terms of pine trees in mycorrhizal association with saffron milk cap mushrooms, production can begin after 4 to 5 years and in this case, according to location, altitude and type of soil, we must also choose the best adapted variety of pine tree. On our website you will also find information concerning the necessary care.

Concerning the care of these seedlings, we provide the necessary practical advice at the moment of their purchase.

And the trunks?

Hongo creciendo en la corteza de uno de los troncos.

Shitake mushrooms are among those that take the longest to fructify after the wood is inoculated.

The time it takes for trunks to begin producing depends on the variety of mushroom inoculated and the type of wood. As we’ve mentioned, the trunks must undergo a process of incubation from the moment they are inoculated until they are placed in their definitive spot. This incubation period is shorter for the oyster mushroom (Pleurotus ostreatus), from between 2 and 5 months. The poplar mushroom takes 6 months, and the shitake mushroom, 9-12 months.

Once the trunks are placed in their definitive spot and depending on the hardness of the wood, they will produce mushrooms for several years, generally between three and six years. Every so often, they will surprise us by producing striking, beautiful mushrooms. They don’t always begin production the first season. We must bury part or almost the entire trunk in the ground and keep the soil around it humid. Excess watering won’t make the mushrooms appear any sooner.

The appearance of the mushrooms based on the soil’s humidity and the type of wood is also conditioned by environmental humidity and temperature. They generally appear in autumn and spring, but by playing with different varieties and depending on where we live, they can also appear in summer and winter, given that some mushrooms adapt better to heat and others to cold (as long as these temperatures are not extreme). 

The trunks can produce around 15-20% of their weight in mushrooms over the course of the entire productive cycle.

And the king trumpet mushroom?

Field eryngo appearing in April-May.


The king trumpet mushroom lives in the root of the field eryngo (Eringyum campestre), the fungus grows feeding on the root of this variety of thistle and the mushroom appears when climate conditions are favorable to it, generally in autumn. Although it isn’t common to have field eryngo in the orchard or garden, we can sow it, or else find a zone where it already exists naturally. We provide the inoculum (as well as the seed of the field eryngo if you request it) and some simple advice on how to use it. Each inoculation spot, if it takes and there is abundant field eryngo in the vicinity, will produce mushrooms.

Setal de setas de cardo.

Already developed field eryngo in early summer.

A mushroom bed is an area of terrain with the presence of field eryngo where the mycelium of the mushroom acts by moving in the subsoil from one root to another neighboring root and produces mushrooms when temperature and humidity are propitious.

Setas de cardo cultivadas en uno de los setales. 

King trumpet mushroom in autumn beside the now dry field eryngo. The field eryngo is an annual perennial plant.

The production and duration of the mushroom bed will depend on the density of the field eryngo and the size of the area it occupies. Some mushroom beds last for many years (more than 10 years) and others cease to produce even while there is still field eryngo.

Can I place the trunks with mushrooms and the mycorrhizated trees anywhere?


The site must be clean and uncontaminated, the soil and air, along with the water used for irrigation, must be unpolluted, given the facility by which mushrooms and the mycelium of the fungi can absorb heavy metals or undesirable chemical ingredients. As for other concerns, in terms of the trunks, they should be placed in a shady spot, ideally one that generates a humid, shaded environment. The mushrooms that live in this way in nature appear in woodlands, black poplar and poplar groves and riverside copses where the microclimate that is generated favors the appearance of mushrooms.


What is the minimum distance that should exist between one trunk and another?

 It isn’t necessary to place the trunks far apart; they should be placed at just enough distance so that when mushrooms appear, they’re not in each other’s way. A distance of 15 cm is sufficient.

And between trees?

 The distance between trees should be various meters; for truffles this distance can be from 4 to 7 meters, while for saffron milk cap mushrooms and other fungi, the distance can be from 2 to 4 meters..