Human interactions with fungi the weather, and in the case of dry rot caused by "Serpula lacrymans", also of timbers in largely dry houses. Some wood-decay fungi such as the honey fungi, species of "Armillaria", are parasites of living trees, attacking their roots and eventually killing them, and continuing to decompose the wood when they are dead. Honey fungus is a serious horticultural pest, as it can spread from tree to tree by long strap-shaped rhizomorphs in the soil. Fungi are important crop pathogens, as they reproduce rapidly, affect a wide range of crops around the world, cause some 85% of plant diseases, and
Mycelial cord uninfected parts. The cords of some wood-rotting fungi (like "Serpula lacrymans") may be capable of penetrating masonry. The mechanism of the cord formation is not yet precisely understood. Mathematical models suggest that some fields or gradients of signalling chemicals, parallel to the cord axis, may be involved. Rhizomorphs can grow up to in length and in diameter. Mycelial cord Mycelial cords are linear aggregations of parallel-oriented hyphae. The mature cords are composed of wide, empty vessel hyphae surrounded by narrower sheathing hyphae. Cords may look similar to plant roots, and also frequently have similar functions; hence they are also called