FIG. 1. Mycorrhizae in situ: (A) arterial arbuscular mycorrhizae (AM) hyphae extending from a root of Artemisia californica beyond the root hairs into the surrounding soil matrix, and (B) an EM infection consisting of several root tips encased in a fungal mantle, with a rhizomorph extending from those tips into the surrounding soil. Both images were acquired using a Bartz Technology Corp. minirhizotron, Model BTC-100X.