@article {Koski165, author = {Ronda Koski and William R. Jacobi}, title = {Tree Pathogen Survival in Chipped Wood Mulch}, volume = {30}, number = {3}, pages = {165--171}, year = {2004}, doi = {10.48044/jauf.2004.020}, publisher = {Arboriculture \& Urban Forestry (AUF)}, abstract = {Uncomposted wood chips are often used as landscape mulches. Chips are commonly derived from landscape trees removed because they were in poor health and often contained plant pests. Chips are also derived from pallets and other wood packing materials that may harbor indigenous and exotic plant pathogens. A study was initiated to determine how long a fungal plant pathogen could survive in uncomposted wood chip mulch in an urban landscape. Thyronectria austroamericana, the causal agent of Thyronectria canker in honeylocust (Gleditsia triacanthos) trees, was used to inoculate branches of honeylocust trees. Cankered branch pieces were placed into mulched areas surrounding honeylocust trees growing under two irrigation regimes. Thyronectria austroamericana recovered from cankered wood pieces after 98 weeks produced cankers when inoculated into branches of honeylocust trees. Irrigation regimes did not affect recovery of the fungus. Cankered wood pieces remained a source of inoculum for 143 weeks after placement in the mulched areas. Due to the longevity of pathogen survival, uncomposted mulch derived from honeylocust trees infected with T. austroamericana should not be placed around honeylocust trees in urban landscapes. Using uncomposted wood chips derived from wood packing materials could increase the risk of introducing exotic plant pathogens to urban landscapes.}, issn = {1935-5297}, URL = {https://auf.isa-arbor.com/content/30/3/165}, eprint = {https://auf.isa-arbor.com/content/30/3/165.full.pdf}, journal = {Arboriculture \& Urban Forestry (AUF)} }