The long-lived five-needle pines, Pinus flexilis (limber pine) and Pinus longaeva (Great Basin bristlecone pine) can co-occur and may form symbiotic partnerships with the same species of ectomycorrhizal fungi. These shared symbiotic relationships may facilitate the persistence of these pine species. Throughout their lives, P. flexilis and P. longaeva may also assemble unique elowground fungal communities, adding to the conservation value of ancient trees. We used MiSeq sequencing of fungal rDNA to compare fungal community similarity for co-occurring P. flexilis and P. longaeva roots and soils in an old-growth forest at the Utah Forest Dynamics Plot, Utah, USA. We cored trees to measure their age and determine whetherfungal communities change with advanced tree age. We found 720 amplicon sequence variants associated with P. flexilis roots, 736 with P. longaeva roots, and 199 that were shared between the two pines. Root-associated fungal communities were significantly different between P. flexilis and P. long eva despite similar soil communities. The fungal community composition on P. flexilis roots and around P. longaeva soil was associated with advanced tree age up to 1340 years. The root-associated fungal community of P. flexilis and the soil community of P. longaeva increased in dissimilarity with tree age, indicating that age heterogeneity within old-growth stands promotes fungal diversity. The significant differences in root-associated fungal communities between the two pine species highlights that they are likely engaged in different bi-directional selection with fungal communities.

Author ORCID Identifier

Joseph D. Birch

James A. Lutz

Benjamin L. Turner

Justine Karst



Document Type




File Format

.zip, .txt, xlsx

Publication Date



Natural Science and Engineering Council of Canada

Utah Agricultural Experiment Station

Smithsonian Institution ForestGEO


Utah State University

Award Number

Utah Agricultural Experiment Station project 1153 Utah Agricultural Experiment Station project 1398 Utah Agricultural Experiment Station project 1423


Trees were cored and tree-rings measured to estimate the age of each tree. Soil and root samples were taken around P. flexilis and P. longaeva and environmental DNA was extracted for amplification. The ITS2 region was amplified to identify fungal communities of each root and soil sample. Fungal sequences were quality filtered and rarefied to 90% of the minimum read abundance.

Scientfic Names

Pinus flexilis, Pinus longaeva

Referenced by

Birch JD., Lutz JA, Turner BL, and Karst J. (in review). Divergent, age-associated fungal communities of Pinus flexilis and Pinus longaeva. Forest Ecology and Management.

Start Date


End Date



37.66° N, 112.85° W



Code Lists

ASV: amplicon sequence variant

DBH: Diameter at breast height (1.37m) in centimeters

UFDP: Utah Forest Dynamics Plot


Single file dataset: UFDP_Tree_Fungi_data.xlsx - an excel spreadsheet with separate sheets for tree data and fungal sequence abundance.


Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.




Additional Files

README.txt (5 kB)
MD5: 34b5788de3fdd90a3278f8c85ee4b743

UFDP_Tree_Fungi_data.xlsx (680 kB)
MD5: 15da77d24598c1c8ef48125c8b31f524