Strengthening our Community Tree Canopy Through Education Module #6: Root Systems of Trees & Palms Laura Sanagorski, Environmental Horticulture Extension Faculty

Strengthening Our Community Tree Canopy 2012 Urban Forestry Series This series is a part of a project titled “Strengthening Our Community Tree Canopy Through Education”. This project is made possible by  a grant through the 2011 National Urban and Community Forestry Grant Program and the Florida Department of Agriculture and Consumer Services, and the Florida Forest Service.

Root Systems – Trees & Palms

Root Zone of Root Hairs Zone of Elongation Apical Meristem Root Cap International Society of Arboriculture, International Society of Arboriculture, Bugwood.org

Healthy root systems grow away from trunk Broadleaf tree roots continue to increase in diameter Example of good root structure- roots grow away from the trunk and don’t circle or girdle. Photo: UF Laura Sanagorski

Facts About Roots Most trees don’t have tap roots Roots grow well beyond dripline Damaging roots on one side of a tree can cause damage to the canopy on that side Root pruning stimulates growth near the cuts Andrew Koeser, International Society of Arboriculture, Bugwood.org

Facts About Roots Circling roots do not continue to circle once planted in the landscape Most roots are in the top 3’ of soil with the majority in the very top International Society of Arboriculture, International Society of Arboriculture, Bugwood.org

Palm tree roots do not increase in diameter Palm Roots Photo: UF Laura Sanagorski Palm tree roots do not increase in diameter Continuous generation, mostly primary and secondary roots that live ~ 3 years ROOT INITIATION ZONE

Palm Roots Photos: UF Laura Sanagorski

Palm Root Regeneration Species Root-stub length (inches) Avg. no. of new roots <6 6-12 12-24 24-36 Cocos nucifera 47 61 50 20 Phoenix reclinata 2 8 32 62 Roystonea regia 1 6 24 36 97 Sabal palmetto 3 196 Syagrus romanzoffiana 41 49 57 13 Washingtonia robusta 14 31 59 144 Table 1. Average percentage of cut roots branching in four different root-length classes.- From Broschat and Donselman (1984; 1990).

Strengthening our Community Tree Canopy Through Education Module #6: Root Systems of Trees & Palms Laura Sanagorski, Environmental Horticulture Extension Faculty