A Tuber melanosporum plantation established in 1994/5 on Kibbutz Bar’am (in the Upper Galilee, Israel, Fig. 1) gradually lost its T. melanosporum mycorrhiza. When checked in 1998, only about 70% of the trees maintained their original mycorrhiza (Kagan-Zur et al. 2001) and was deteriorating constantly. A number of trees per-ished. Several different tree species were initially introduced.