Beach Dune Habitat Management and Seagrape Pruning

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Presented at the South Florida Native Plant Seminar Presented at the South Florida Native Plant Seminar October 18-19, 2023 October 18-19, 2023 Naples Garden Naples Botanical Botanical Garden


Thank you to our sponsors


BEACH DUNE HABITAT DEVELOPMENTS IN MANAGEMENT POLICY AND AND SEAGRAPE PRUNING PRACTICE OF DUNE RESTORATION

AND MANAGEMENT

How a continuing obsession with one species harms the ecosystem as a whole.

Robert H. Barron, Coastal Management and Consulting, Coastal Growers Inc. Continuing Education Credit Course presented for Landscape Architects and Natural Resource Managers, , FLORIDA ASSN. OF NATIVE NURSERIES


This presentation is a condensation of materials delivered to a number of objective hearings and committees reviewing the issue of pruning seagrape, Coccoloba uvifera, in context of management of beach dune systems, in southeast Florida. Basic tenets include: • • • •

Seagrape was not a dominant plant in the natural historic condition. Seagrape is a fast growing and brittle wood which fares poorly in a storm, and in tree form breaks apart and uproots. Seagrape, if not controlled is highly invasive; overshadowing and killing other components of the dune system. Seagrape can be heavily pruned, in a comprehensive program of dune habitat management, with overall reduction in turtle nesting habitat light pollution.

Robert H. Barron Coastal Management Consulting 561-441-1446, <beachmaker@aol.com>


Basic tenets:

• Seagrape was not dominant • in the natural historic condition. First description of Florida dune, by Jonathon Dickinson 1696..”no trees, but only sand hills covered with shrubby palmetto” Floristic inventories by Craig, 1974, 132 sites, seagrape dominant on 9%. and Richardson, 1977, “all parts of the strand habitat, the dominant species is Serenoa”.


Ocean to river was palmetto dominated strand in natural condition. Historical photos and literature yield character of the wild dune.


Palmetto Park and A1A location, Boca Raton ca 1925. Ocean to river was palmetto scrub. No tree form seagrape.


1876 US LIFESAVING SERVICE HOUSE OF REFUGE, DELRAY BEACH

PALMETTO SCRUB.. NO TREES


EARLY DELRAY BEACH COASTAL HOMESITE..no trees.


DELRAY BEACH CLUB SITE CA 1950

NO TREES except Australian pines Scrub species and palmetto


SEAGATE DELRAY. 1951 early development in natural system..


From FLORIDA DUNES AND SCRUB, Florida Geological Survey, 1942


Compare to

CANAVERAL NATIONAL SEASHORE, 2017 20 plus miles of coastal strand in natural condition


SPESSARD HOLLAND BEACH, BREVARD COUNTY, 2014


EXISTING COASTAL STRAND IN NATURAL CONDITION is the model for our dune management program.


Seagrape was historically controlled to shrub height by occasional freezing temps. NOAA historical records demonstrate much more frequent freezing episodes throughout South Florida, but less and less as urban heat sink increased with development. A three day hard freeze destroyed agriculture in Delray in the 1920’s.

1991 freeze at Atlantic dunes

Seagrape, cocoplum frozen to grade


1991 freeze incident, Boca Raton Park. Explains historic regional domination of palmetto in strand. Even today, seagrape not common above Daytona.


. Basic tenets:

Seagrape is a fast growing, shallow rooted and a brittle wood which fares poorly in a storm. Tree forms uproot and break apart, delivering damaging missiles to the wind. “The Worst Tree”, as described by U. of F. study.. Hurricane Andrew Damage to the Urban Forest, A Preliminary Evaluation”


“The Worst Tree” University of Florida Study HURRICANE ANDREW DAMAGE TO THE URBAN FOREST: A PRELIMINARY EVALUATION Duryea et al

Crandon Park, 2 weeks after H. Andrew


Excavation of oceanfront development site reveals comparative depth of Coccoloba (dark color) vs Serenoa (light) roots. Half of seagrape rootmass is in top 8 inches of soil, from Eisenstadt, UF Citrus Lab study “Seagrape Root Distribution Following Hedging’


Seagrape tree toppled by tropical storm force winds Ilustrates shallow root system.


Basic tenets:

• Seagrape if not controlled is highly invasive; overshadowing and killing other components of the dune system.

Robert H. Barron Coastal Management Consulting 561-441-1446, <beachmaker@aol.com>


Seagrapes planted in 1980 did not begin to thrive until after sea oats foredune was

installed six years later..then grew to 25 ft. in the next 16 years.

6 year old seagrape clusters, installed at Delray Beach at 10 X 15 feet


Section 17 Seagrape expansion since 1985 Red line is approximate footprint of seagrape clusters as installed to trap sand at access points 1982; about 300 sq ft. Yellow is footprint at time of 2001 FDEP pruning permit; about 4,500 sq.ft. White line is seagrape footprint at 2015 FDEP exotic removal permit; about 10,500 sq. ft. 35X increase since planting, 2.3X increase since pruning began. 7% /year, expansion since pruning began.

CAN DOUBLE IN FOOTPRINT EVERY 9 YEARS 80 ft


20 years after planting..

Comprehensive Dune Management Plan was written in 1997, to include exotic removal, pruning, replanting.


phototropic habit of coccoloba leaves large areas under canopy unrooted and vulnerable


Deliquescent growth form spreads to light and overshadows everything below. This is a single individual with branches that rooted into ground at touchpoints and started new trunks.


Yucca aloifolia under seagrape canopy in Juno. Struggling and will fail with reduced light.


DEAD SAW PALMETTOS. Remember that this was the dominant species in the natural state. Shading by seagrape has killed most of the native strand species which occupied this park only 20 years ago. Rare and listed plant species are lost. This was a choice!


Overshadowing has cost most of the biodiversity. The rich natural character is all but lost..


What remains is a near sterile monoculture.


only seagrape


WHY IS SEAGRAPE SO COMMON ON THE DUNE? Cheapest and fastest growing nursery plant with the word “sea” in common name First shrub species designed in to new Beachfront landscape plans.


Basic tenets:

• Seagrape can be heavily pruned, in a comprehensive program of dune habitat management and landscaping with overall reduction in turtle nesting habitat light polution. Robert H. Barron Coastal Management Consulting 561-441-1446, <beachmaker@aol.com>


Can be cut almost to grade at any time of year with zero mortality


This dune area was illegally cut to ground level in June of 2019, and has recovered to three feet.


What is the scientific rationale for these pruning height treatments? Why 10 feet?

Why 3 feet?

Why any of this?

Why 15 feet?


Just above bollard height is adequate to shield marine turtle nesting zone from road light


So..What is a reasonable and prudent alternative?

MANAGE FOR THE WHOLE ECOSYSTEM RATHER THAN JUST ONE SPECIES OF TREE


ECOSYSTEM MANAGEMENT OBJECTIVE: Restore the complete natural plant complex and full habitat function.


Objective FDEP evaluation yields permits to do this.

2004 FDEP approved plan


Work in progress.. exotics removed..

But wait !

Uninformed public ALWAYS freaks out, like early controlled burns. County ERM complains to FDEP and work is halted.


However, the science holds up, and

after much turmoil and thorough review, FDEP reaffirms, approves, and funds the comprehensive habitat managent program.


March 2017, most recent FDEP permitted coppicing, exotic removal, species enhancements, to guidelines of international Society for Ecological Restoration.


Comprehensive Habitat Restoration

A 35 year project More than 110 species, including threatened and endangered State and Federal species, several rescued from at risk locations, including County Parks.


from International Standards for the Practice of Ecological Restoration

Society for Ecological Restoration acknowledges Delray Beach dune project based on these principles as example of 4/5 star recovery.


SO..What about permits to prune or modify the dune? STATE FDEP Coastal Construction Control Line review will determine what permit level is required. either: Exempt ( risky but no cost), Field Permit (simple, low cost, quick), or Admin Permit (complex, costly, slow). And there are a few conflicting local or county processes as well.



So? Exemption, Field Permit or Admin Permit?? Googley search for “seagrape pruning, Florida” yields..

FDEP CCCL DUNE PLANT MAINTENANCE GUIDELINES 2022 ..revised recently to reflect contemporary science and habitat management practice.

Safest, best option is to ASK the local FDEP Field Agent. Search “FL CCCL field agents” Or call FDEP CCCL Program for direction, 850-245-2094


FDEP Field Permit is best option.

Permit No. _______________ - __________

SPECIAL PERMIT CONDITIONS: The permit is valid only after all applicable federal, state, and local permits are obtained and does not authorize contravention of local setback requirements or zoning or building codes. This permit and public notice shall be posted on the site immediately upon issuance and shall remain posted along with local approval until the completion of any activity authorized by this permit. Other special conditions of this permit include:

No fees, Minimum prep costs STANDARD PERMIT CONDITIONS: The permittee shall comply with the attached standard field permit conditions. APPLICANT INFORMATION: I hereby certify that I am either: (1a) the owner of the subject property or (1b) I have the owner’s consent to secure this permit on the owner’s behalf; and that (2) I shall obtain any applicable licenses or permits which may be required by federal, state, county, or municipal law prior to commencement of the authorized work; (3) I acknowledge that the authorized work is what I requested; and (4) I accept responsibility for compliance with all permit conditions. Applicant’s Signature_____________________________________ Date______________________ Telephone No. (____)________________ Applicant’s Printed Name_______________________________ Address_________________________________________________________ If applicant is an agent: ________________________________________/________________________________________ /(_____)__________________ Printed name of property owner Property owner’s address Property owner’s telephone no.

DEPARTMENT FINAL ACTION AND FILING AND ACKNOWLEDGMENT: This field permit is approved on behalf of the Department of Environmental Protection by the undersigned staff designee, and filed on this date, pursuant to section 120.52, F.S., with the undersigned designated Deputy Clerk, receipt of which is hereby acknowledged. _______________________________________/____________________________________________/______________________ Staff Designee/Deputy Clerk Printed Name of Designee/Deputy Clerk Date EXPIRATION DATE: _______________ (Emergency permits issued pursuant to Section 62B-33.014, F.A.C., are valid for no more than ninety days and other field permits are valid for no more than 12 months. The staff designee may specify a shorter time limit.) EMERGENCY PERMIT:

YES

NO

Approved plans are attached:

YES

NO

Page 2 of 4 DEP form 73-122 (Updated 5/05)

Typically requires drawing with location, project description, exotic species removal, native beach plant species only, no grade changes, lighting caviat.


Sometimes a nightime lighting survey may be required to demonstrate compliance with FWC marine turtle nesting rules. Applicant must show project does not increase risk to hatchlings.

DSC_0184, Nikon D3400 DW_0183, D3400 1 sec, F5.6, ISO 400, Nikon EV1, 55mm 1 sec, F5.6, EV 26.32.58 N, 80.02.31 W, 1,ISO 285° 100, 55mm DX South Studio/Main House


COSTLY ENGINEERING NOT REQUIRED FOR FIELD PERMIT

Hand drawing includes location, dimensions, existing and proposed conditions. Complies with Field criteria.


What are pruning costs, methods?

Delray Beach, 6,840 feet, three machete cuts/yr, $35K to $40K annually , with staff labor.


Sloans Curve Condo, Palm Beach. First FDEP permit for tree reduction and hedge pruning . 1990

Maintained at 42 inches for 27 years, Four machete cuts/yr, $4,800, 600 feet.


SHI Condo, 600 feet shoreline X 25 feet. Hand pruned monthly, $6K annual cost


HOW?


Cost of not pruning?

Two seasons with no pruning and 36 inch grows to 6 to 9 feet above grade killing most other beneficial species.


Seven months of neglected pruning

Five feet verticle growth


Two years no pruning 9.5 ’

Look for the guy with the mask!


Back to chain saws after two year neglect

THE COST for single repair pruning.. nearly $100,000.00


FDEP permitted Hutchinson Island project under way 2020 cuts overshadowing seagrape 12 to 24 inches above grade for maintenance at hip high, and installs 8600 saw palmettos and other strand zone plants (50 + species) on 1 mile of shoreline.


1/3 Million $ Project

Field permit was secured with simple drawing, based on 30 year Delray Beach model.


FPL DUNE HARDENING PROJECT. Including removal of exotic plant species, pruning native species to restore strand growth habit, and enhancement planting with FDEP approved coastal native species per attached FPL St. Lucie Power Plant Dune Hardening Project Description. Approximately 4650 feet shore parallel from about FDEP monument SCR-085 at the North, to SCR-079 to the South, and from the high water line on the East to the upland base of the dune berm on the West.

N

➤ 1000 ft

Application also included location plan, listing of plant species, and short narrative re irrigation and access. No sprinklers.. Entire project watered by hose.


Permits are for one year, but subsequent maintenance is exempt.

2013 Juno By The Sea project cut seagrape to shrub height, replanted historically correct species mix, and modified all upland lighting to FWC standards. Rare plants included. Annually maintained exotic free.


So, if not seagrape, then what species?

Blackbead, Pithecellobium keyensis Florida Privet, Forestiera segregata White indigoberry, Randia aculeata


The dominant plant in the natural ecosystem was saw palmetto..very deep roots, best for storm resistance


Golden creeper, ( Ernodea litorallis) Blackbead, (Pithecellobium)


Cocoplum coastal variety, aka “horizontalis Chrysobalanos icaco


Most coastal shrubs are compact leaf, dense and shearable, evolved under salt spray.

Randia aculeata, white indogoberry


Well adapted to high energy salty environments


But can be maintained long term in formal oceanfront Landscapes.


This is an entirely man made dunescape


FANN growers can provide 60+coastal species


So a deeper look at native dune species, solutions

Robert H. Barron Coastal Management Consulting 561-441-1446, <beachmaker@aol.com>


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