INOCULATION AND FIELD TESTING OF SITKA SPRUCE AND DOUGLAS-FIR WITH ECTOMYCORRHIZAL FUNGI IN THE UNITED-KINGDOM

Picea sitchensis and Pseudotsuga menziesii seedlings were grown in con tainers, inoculated with ec; tomycorrhizal fungi, and planted in Briti sh forestry sites. Root samples taken during the year after planting w ere assessed for mycorrhiza formation. Survival and shoot height were assessed at the end of each year. Observations were made each autumn o n the occurrence of sporophores of ectomycorrhizal fungi. Pot experime nts were used to assess the colonization potential of soils from the e xperimental locations. Assessment of mycorrhiza formation by the inocu lant fungi both before planting and the following year showed much var iation among the fungi used. Similar variation was found among field s ites. Inoculation with Laccaria isolates was most successful. Height m easurements are reported for the first 2 years after planting, at whic h time there were few significant effects on growth of Picea sitchensi s or Pseudotsuga menziesii seedlings. Experimental assessment of colon ization potential was of little value in this work for predicting even ts in the forest.