This study investigated ¹³C and nutrients transfer between Ponderosa pine saplings and fungal hyphae in the Sierra foothills of Northern California. Soil amended with ¹⁵ N, Rb, Cs and P was separated from surrounding soil by 25 μm root-restrictive stainless steel screens. Two screens were glued to each end of 5 cm ID PVC pipe and separated by a 5 mm spacer to establish an air gap between the hyphal chambers and surrounding soil to limit diffusive nutrient movement. The study was conducted near Marysville, CA at north facing meadow site populated with a young group of P. pine saplings. After the hyphal chambers had been in the ground for 1 month, labeled N was applied as ¹⁵N in May 2004. Needles were sampled, dried and analyzed for ¹⁵N and Rb three, six, seven, and eight months after fertilizer application. A second pulse of ¹⁵N was added to the hyphal chambers in April 2005. Eight days after the second ¹⁵N application, the saplings adjacent to the hyphal chambers were labeled with ¹³CO₂ (99% ¹³C). One week later, the saplings and hyphal chambers were harvested along with soil adjacent to the screens and below the P. pine sapling. Foliage, stems, roots and soil outside the hyphal chambers and hyphae and soil within the chambers were dried and analyzed. The bait trap soil and hyphae were enriched with ¹³C. Concentrations of ¹⁵N in the treated P.pine needles were higher than in the controls. Rubidium concentrations in two treated saplings did not indicate transfer from the treated soil. However, the remaining six replications were significantly higher than background levels. Since roots can not penetrate the screens and because the soil did not become saturated, it appears that Ponderosa pines saplings received ¹⁵N and Rb via transfer through mycorrhizal hyphae.