PALM PALM DISTRICTS IN HISTORIC MAINTENANCE City of Phoenix Historic Preservation Office 200 W. Washington St., 17th Floor Phoenix, AZ 85003 reservation Planner, Historic Preservation Office Historic Preservation reservation Planner, 1/09 500 P Recreation Department; Design by Erika Finbraaten, Historic Recreation Text by Richard van-C. Adkins, Forestry Supervisor, Parks and Parks by Richard van-C. Adkins, Forestry Supervisor, Text Palms have been a part of the Phoenix area While palms located in their to be patient and wait for the flowering cycle to landscape since the early 1900s. The palm’s natural habitat do not need be complete. Otherwise, if pruned too early, stately appearance has come to be associated not pruning, palms in an urban additional flower stalks may develop and will hang only with the pioneering history of the area, but a environment do require annual from the palm head the remainder of the year. comforting desert oasis feel in the Valley of the maintenance to remove dead Sun. Palms have been planted throughout fronds and fruit stalks that can As a general rule, plan neighborhoods and business districts by residents become unsightly and to begin pruning date and developers, often defining the landscape potentially hazardous. palms in late May and palette of the surrounding community. In the fan palms in mid- city’s historic districts, they are a character June. Cut fronds close defining feature. Severely over- Correct pruning is a key to the petiole base of pruned date palm component to maintaining palm the frond (the petiole health. Many people base is where the indiscriminately cut palms to remove nearly all of Properly pruned fan palm palm frond attaches the fronds. This tendency to over-prune palms is to the trunk of the not a recommended practice and can harm the palm) without damaging the live trunk tissue. palm’s health over time. The use of climbing Live, green fronds manufacture food for the palm spikes should be and should be left as long as possible. Palms do minimized. Even not store energy as efficiently as trees and severe though most street pruning can deplete energy resources and stress landscaped palms can palm health, causing a gradual decrease in trunk be pruned safely from diameter and strength. an aerial lift, some palms still need to be The following are nationally accepted climbed. Palms do Properly pruned date palm arboricultural maintenance standards for pruning not compartmentalize palms: and seal wounds like trees. Injuries to palm trunks are permanent. Retaining the petiole There are four main species of palms found in the Palm fronds should not be bases or peel on palm trunks helps protect palms street landscapes of Phoenix: pruned higher than fronds from spike injury. originating at a 45-degree angle • Two species of fan palms: from horizontal. This method There are numerous certified landscape and tree - the California fan palm retains adequate live, green contractors that can provide palm pruning (Washingtonia filifera), and fronds to produce food for the services. Information regarding the hiring of local palm while removing brown, - the Mexican fan palm arborists and additional resources concerning the dead fronds and fruit stalks. (Washingtonia robusta) care of palms and trees can be found at the Date palms often are pruned to following Web sites: fronds originating at a 60- • Two species of date palms: degree angle from horizontal to - the date palm (Phoenix Severely over- www.treesaregood.org isa-arbor.com provide a fuller, more tropical pruned fan palm dactylifera), and aztrees.org treelink.com look. phoenix.gov/FORESTRY - the Canary Island date palm (Phoenix canariensis). Removing flower stalks prior to the development and set of the palm fruit can save pruning time For additional information, contact the Historic Preservation Office at 602-261-8699 or Parks and Although people often refer to palms as “trees,” and money as well as the energy resources of the Recreation Department at 602-262-6501. they technically are not true trees. Palms are palm used in forming the fruit. Date palms in considered arborescent monocots, or “tree-like Phoenix flower each year in April and May, while For more information or a copy of this publication in an grasses.” Palms differ structurally from trees in fan palms flower in May and June. When planning alternate format, contact Mary Reyna at 602-261-8699/voice the development and organization of growth cells. annual pruning maintenance activities, it is best or 602-534-5500/city TTY relay..