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In 1992, Hurricane Andrew destroyed over 1000 mature trees in the City of North Miami, located 50 mi north of the storm center. The cleanup cost over $1,000.000. Most of the tree failures were caused by structural faults: co-dominant leaders, narrow limb attachment, included bark, over-lifting, hatracking, poor vertical limb placement, crown imbalance, overly-dense crowns, crossing and in-growing branches. All could have been corrected with proper pruning. Action was taken to reduce future damage. The city arborist made a complete, computerized inventory of all trees on public property, creating a data-base with all structural problems identified. These were prioritized so the worst could be addressed first. After any pruning work was done on a city tree, a follow-up evaluation was made, and any additional pruning needed was scheduled. Pruning followed the recommendations of state specialists and three county extension agents with the University of Florida Cooperative Extension Service. City workers were taught using lectures, demonstrations, site visits, CES publications, and individualized instruction. In addition, all new trees purchased were grades FL Fancy or FL no. 1, based on Grades and Standards for Nursery Plants; such trees require little or no corrective pruning at planting and mature as structurally-sound trees which resist wind damage. Two later storms (1993, 1999) produced winds in North Miami similar to those of Hurricane Andrew. Together they destroyed only 35 trees which cost $35,000 to remove. These data demonstrate that following CES pruning recommendations reduces storm damage to trees, saving money and preserving the urban forest canopy.

Published by the South FL Garden Club in 1928, when Mabel Dorn was president and Marjory Stoneman Douglas—famous for championing the protection of the Everglades—was garden editor of the Miami Herald, The Book of Twelve lists twelve tried and true flowering and shade trees, large to small shrubs, etc. for southern Florida, but also includes some plants which are now tried and true invasive species. The book was reviewed in July 2004 by the Univ. of Florida (FL)/Miami-Dade Florida Yards and Neighborhoods (FYN) Extension Agent in response to a request from a local garden club, which as a club project, had decided to re-print and distribute the book to its 100 members. Because it might encourage the use of invasive species, the review was discussed at a seminar on ecologically sustainable alternatives to invasive species. One recommended plant, Schinus terebinthefolius (Brazilian pepper) is now prohibited by the FL Dept of Environmental Protection and considered a noxious weed by the FL Dept of Agric and Consumer Services. The FL Exotic Plant Pest Council (FEPPC) considers five plants Category I invasives, i.e., exotics altering native plant communities, displacing natives, changing community structures or ecology, or hybridizing with natives. These include Lantana camara, Lonicera japonica, Abrus precatorius and Asparagus africanus. Ten plants are FEPPC Category II invasives, exotics increasing in abundance or frequency, but not yet altering plant communities as extensively as Category I species: Cestrum diurnum, Murraya paniculata, Sesbania punicea, Cryptostegia grandiflora, Jasminum sambac, Antigonon leptopus, Macfadyena unguis-cati, Asystasia gangetica, Wedelia trilobata, and Tradescantia fluminensis.