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and certain genera of palms, such as Mexican fan palms (Washingtonia robusta), can accumulate large collars of dead and highly flammable fronds. As a result, palms cannot be pruned using the same standards as broadleaf and conifer trees. Pruning practices should emphasize removing dead fronds and skinning the trunk to minimize the accumulation of dead material. Pruning to maintain clearance is generally not necessary 2 unless the tree is near a roof or chimney. Special Pruning Standards for Species that Produce Large Amounts of Flammable Debris –The pruning practices described above address the requirements for trimming and removing flammable branches to create adequate vertical and horizontal spacing. However, some tree species with growth characteristics produce flammable or dead material that is not addressed by pruning branches. Some species of eucalyptus trees (primarily Eucalyptus degulpta and Eucalyptus globulus) shed their bark in heavy quantities, which produces high volumes of dry and flammable debris at the base of the tree. This pile of bark can readily ignite and spread fire quickly. All dead wood and flammable debris should be removed from the tree before each fire season. An International Society of Arboriculture-Certified Arborist is recommended to complete tree pruning per American National Standards Institute A300 specifications (ANSI, 2017). This will ensure tree pruning complies with wildfire hazard area maintenance recommendations and supports tree longevity. The City of Pleasanton does not require a permit to prune trees; however, pruning should be done in accordance with International Society of Arboriculture pruning guidelines. Topping is not an approved pruning pra ctice as it creates a hazardous canopy with weakly attached limbs prone to failure. Tree Pruning for Utility Clearance Vegetation contact with aboveground electrical equipment is a common cause of fires ignited by electrical utilities. In 2023, contact with vegetation was the cause of 19% of fires ignited by PG&E equipment (CPUC 2024). Maintaining adequate clearance between high-voltage electrical equipment and nearby vegetation is the responsibility of the electric utility, which is PG&E within Pleasanton city limits. Within the WUI areas of the City, PG&E is responsible for maintaining at least four feet of clearance between its high-voltage equipment and nearby vegetation for wires carrying 22.5 kV or less, 6 feet of clearance for wires carrying from 22.5 to 72 kV, and 10 feet of clearance for lines carrying more than 110 kV. The utility is also responsible for removing branches likely to fall onto their equipment regardless of distance. Healthy, stable trunks and major branches are exempt from this requirement since they do not readily ignite. Electrical utilities are not required to maintain specific vegetation clearances around low-voltage wires and service drops. However, they are required to maintain vegetation near their electrical lines, including low voltage lines, if the vegetation is abrading or damaging the line. 2 Because live fronds do not readily ignite and removing or damaging the fronds near the heart of the palm can kill the tree. 18