Soil cores collected in June and September 2006 and all woody roots separated from soil cores.

All viable roots from each core were bead beaten to extract DNA, amplified with labeled ITS2 primers

58A2F (6FAM) and NLB4 (HEX).

PCR product was cut with restriction enzyme AluI and HaeIII to generate 4 TRFLP profiles per core. Since the NLB4 labeled primer generated the same

size peak for most samples with AluI, we had 3 community profiles to use for identification of root

fungi (below).

DNA was extracted from sub-sampled

ECM root tips

DNA was extracted from forest soil, amplified with ITS primers and cloned.

Sporocarps were collected and DNA was extracted.

These 3 sources of environmental DNA were used for database construction.

DNA was sequenced using ITS primers and fungi were identified by comparison to EMBL/GenBank/DDBJ database entries.

DNA was used for PCR with labeled ITS2 primers. TRFLP with AluI and HaeIII resulted in 3 distinct TRFs that together comprise

the “fingerprint” for the fungal type.

Fragsort was used to identify fungi in complex communities using our database. AluI 58A2F

HaeIII 58A2F

HaeIII NLB4

58A2F (AluI)

NLB4 (HaeIII)

58A2F(HaeIII)Table S1