Mycorrhizal network

Ectomycorrhizal hyphae extend out from one plant's roots they often encounter the root systems of other plants. If those plants also associate with ectomycorrhizal fungi, the hyphae will often grow around the root and create a new mycorrhizal structure. In this way, two plants can be linked into what is called a "common mycorrhizal network". The networks can link individuals plants of the same species or of different species.

Discovery

These networks were first observed in laboratory studies that used glass boxes, which allowed researchers to visually follow hyphae. The hyphae are both small and fragile and any disturbance of the soil often breaks hyphal connections. So researchers were unable to dig into the soil to see the networks without destroying them.

References

• Kennedy, P.G., Izzo, A.I., and T.D. Bruns. 2003. There is high potential for the formation of common mycorrhizal networks between understory and canopy trees in a mixed evergreen forest. Journal of Ecology 91: 1071-1080.
• Horton, T.R. and T.D. Bruns. 1998. Multiple-host fungi are the most frequent and abundant ectomycorrhizal types in a mixed stand of Douglas fir (Pseudotsuga menziesii) and Bishop Pine (Pinus muricata). New Phytologist 139: 331-339.
• Nara, K. 2005. Ectomycorrhizal networks and seedling establishment during early primary succession. New Phytologist. In press.