Loading...
RESOURCE MANAGEMENT PLAN 4/88 RESOURCE MANAGEMENT PLAN FOR SAND PINE SCRUB PRESERVE #1 AND #2, QUANTUM PARK, BOYNTON BEACH, FLORIDA. 27 April 1988 by Donald Richardson, Ph.D. Ecological Consultants 7301 Summerbridge Drive Tampa, Florida 33614 \\\~, ~~';P';;'~~"'T"S"" ~"""'C'" 1 ~--; j i "'..,._"'.-. ,.. i -..n-...-1Ul"...-lliIllf JrlT , . ","'. ~.~ . I1T1111 'IT 0 II [ _,,,,>,,' ;.~I!'.,.<~ 2 Introductibn As per the Development order proposed by the Treasure Coast Regional Planning Council and the City of Boynton Beach, approximately 40 acres of sand pine scrub vegetation was set aside as a nature preserve within the Quantum Park (DRI) project. Since most of the scrub within the above referenced project had been severely disturbed by sporadic understory clearing and livestock grazing, the said 40 acres was divided into two disjunct sand pine preserves (Figure 1). Preserve #1 is located north of N.W. 22nd Avenue and contains about 25.7 acres of sand pine scrub and abandoned dry prairie/pine flatwoods ~abitats (Figure 2A). Approximately 14 acres of this site is dominated by sand pine scrub vevegation. Preserve #2 is located west of High Ridge Road and south of N.W. 22nd Avenue and includes a mixture of 13.0 acres of sand pine scrub and 1.3 acres of disturbed grassland (Figure 2B). The remaining 12 acres of sand pine scrub needed to meet the 40 acre requirement is microsited on many of the commercial development lots throughout the project (Figure 3). The purpose of this report is to define the proposed management philosophy and methodology for longterm preservation of these two preserve sites. BASIC MANAGEMENT PHILOSOPHY The objective of the resource management plan is to preserve, through management, a representative sample of an original Florida ecosystem, thereby maintaining the natural 3 diversity of both plants and animals. RESOURCE DESCRIPTION PRESERVE #1 Disturbances to plant communities have long been viewed as an outside threat to the normal functioning of the community. In the sand pine scrub community, the resilency of most of the indicator species has been attributed to recovery via sprouting from preexisting root stocks, as very few species in the scrub recover via seed (i.e., Ceratiola ericoides and Pinus clausa). The vegetation of the preserve area is characterized as young or early successional sand pine scrub with scattered areas of dry prairie/pine flatwoods. A total of 119 plant species (41% are obI igate to sand pi ne scrub) have been observed wi thin the preserve (Table 1). Although clearing of the understory and thinning of the sand pine occurred prior to 1983, community recovery is rapidly occurring. The overstory trees are dominated by widely spaced sand pine (pinus clausal (138 trees per acre) of at least two different age cl asses (1"'-2121 year sand 2'" -3 5 year s). Tree core data from established permanent plots indicates that the average age of sand pine is 18.34 years old, with the oldest trees (19-36 years) in the northeastern corner of the preserve. There were no trees greater than 38 years, however, hundreds of young sapling are scattered throughout the preserve. Trees vary in size from 2.7- 36.7 cm dbh, reaching heights of 37-46 feet. The shrub layer is dominated by widely spaced scrub oaks 4 (Quercus myrtifolia, Quercus geminata), palafoxia feayi, jointweed (polygonella polygama) and scrub mint (Conradina grandiflora). Average stem densities were highest for myrtle oak (93.8 stems per 5 x 5 m quadrat) and sand live oak (79.8 stems per 5 x 5 m quadrat), while average height was 21.3 - 68.5 cm. One year from the initial sampling effort,0em densities -slightly decreased for both spec ies of oaks ~ but showed some / increase for jointweed (Polygonella polygama) and palafoxia feayi I / I in the permanent sampling plots. I / Changes in shrub stem densities over time for the Quantum Park scrub communities is consistent with other scrubs in south J ~orida. Recent data collected from HI year ~> '~Jonathan Dickinson State Park indicate that field plots at scrub species composition remains fairly constant in mature scrub, however, ~tem densities in oaks shows a 2-3 fold increase/ Changes in shrub densities within the preserve may not change much over the next few years since most of the understory was reduced to the ground surface in 1983. Seed inputs from existing oaks will require longer intervals before new seedlings can be detected. The overall diversity is much higher than compared with other mature scrubs or other areas within Quantum Park (Richardson et al. 1986). Except for the oaks, other characteristic shrubs have begun to germinate in the open areas of the preserve. These shrubs include rosemary (Ceratiola ericoides), rusty lyonia (Lyonia ferruginea), scrub mint ( Con r ad in a g ran d i f lor a), talI 0 ww 0 0 d ( X i m en i a am e r i can a) , and 5 jointweed (polygonella ciliata and ~ gracilis). probably the most dramatic change in the shrub layer has been the establishment of Ceratiola. Rosemary often does not germinate until 2-5 years postfire, and its seedlings do not reach reproductive maturity for 10 to 15 years. To date, more than 25 2 year old shrubs have been observed throughout the preserve area. Johnson (1986) has shown that stand biomass increases slowly from 2 to 4 years, rapidly from 4 to 10 years and less rapidly between 10 and 35 years. The herbaceous component of the preserve area is represented by 92 species, including a large proportion (35%) of weed species that have colonized disturbed areas (i.e., brush piles, -trails and even gopher tortoise mounds). The most common herbs include broomsedge grass (Andropogon virginicus), Cyperus retrorsus, Dichanthelium sabulorum, innonence (Euphorbia polyphyl1a), and hairsedge (Bulbostylis ciliatifolia). Average percent cover for the 8 permanent 1 x 1 m2 plots was 34% in 1987 and 30% in 1988, showing a slight decrease which was largely attributed to a loss of broomsedge grass from the plots. Even though the percent cover decreased from 1987 to 1988, the number of species within the 4 sampl i ng plots increased from 15 to 19. Thi s change was due to an increase in the number of scrub endemics that have germinated throughout the preserve. Some of the more notable species include Bulbostylis, Lechea, Euphorbia, Dichanthelium, Aristida, Croton, and Liatris. Ruderal components have invaded the margins of the preserve 6 due to past disturbance from livestock. Several horses and goats from the adjacent property have periodically entered the preserve. This has resulted in some areas being completely denuded from horses rolling in the sand for insect protection. Also the adjacent properties have been disturbed for such a long time that the ruderal components are well established and potential seed banks are high. SCRUB FINGERS OF PRESERVE #1 Approximately 4 acres of sand pine scrub was created in an effort to increase the total number of acres within the sand pine preserve. A soil mulching technique utilized by the phosphate industry was used to recover 4 acres from former sand pine scrub slated for development on the project. To date, the establishement of scrub vegetation on these newly created ridges has been slow because of invasion by local pasture grasses and weeds, drought, and localized disturbance from livestock. with time, these areas within the preserve will eventually become recognizable scrub in the early stages of development and may be used to eliminate an equivalent amount of scrub from other commercial lots within the project. However, since scrub reclamation is in its infancy, this process may take many years before these areas are acceptable to all parties involved. PRESERVE #2 Historically, this tract of scrub vegetation shares a similar background with the preserve north of N.W. 22nd Ave. in 7 that the understory was cleared in the early 19813's. what's ~interesting about ~his 14 acres is thaT TPgpneration of sand pine h~.!? been prolif ic. This indicates that the type of mechan ical ~isturbance used to clear the understory vpgPTaTion ;n this -'--- portion of the scrub caused l~.~ aisturbsRcQ nf soil profiles when contr~_eted wi~!t the area to the north or conditions were more favorable for seed dispersal and/or germination. Most of the area north of N.W. 22nd Ave. was cleared with a root rake which caused severe mechanical disruption and alteration of soil profiles. Thi s type of clear ing tends to remove a vast amount of underground roots and corms which would normally germinate with time. It appears that the 14 acres south of the N .W. 22nd AVe. was mowed, raked, or bulldozed in a slightly different fashion since many more endemic species and sand pine have germinated over the past 5-6 years. The site is dominated by sand pine (pinus clausa) which range in size from 15-41 cm dbh reaching heights of 16-17 meters. Most of the trees lean to the west because of offshore sea breezes. Tree core data indicates that most of the larger sand pine range in age from 21-45 years (Table 2). Existing sand pine densities within the preserve average about 45 trees per acre. Sand pine recruitment from existing seed bank reserves and periodic release by mature trees has been prolific for this scrub. Seedling densities range from 28/3 to 34/3 trees per acre. The shrub layer is dominated by scattered sand live oak (Quercus geminata), rosemary (Ceratiola ericoides), Palafoxia 8 feayi, jointweed (polygonella polygama), saw palmetto (Serenoa repens), and scrub mint (Conradina grandiflora) (Table 3). A large portion of the tract is covered with a dense mat of love vine (Cassytha filiformis) which has killed many scrub mints. Most of the young rosemary appear to be about 3-5 years old based on nodal counts. The herbaceous layer is composed of wiregrass (Aristida gyrans), silkgrass (Pityopsis graminifolia), scrub sedge (Rhynchospora megalocarpa), hairsedge (Bulbostylis ciliatifolia), sand spike moss (Selaginella arenicola), Dichanthelium sabulorum, prickly pear cactus (Opuntia humifusa), natal grass (Rhynchelytrum repens), broomsedge grass (Andropogon virginicus), and sawbriar (Smilax auriculata) (Table 3). Within the sand pine scrub preserve, approximately 1.3 acres along the western edge of the site (Figure 2B) is best classified as ruderal vegetation. It appears that these areas were once utilized as dump sites for building and residential debris. These areas support a thick grass layer composed of several weedy or exotic species. The dominant species include bahia grass (Paspalum notatum), broomsedge grass (Andropogon virginicus), natal grass (Rhynchelytrum repens), wild grape (Vitis munsoniana), and pokeweed (Phytolacca americana). Other associates include dogfennel (Eupatorium capillifolium), Caesar weed (Urena lobata), begger-ticks (Bidens alba), dwarf horseweed (Conyza canadensis), Sida cordifolia, periwinkle (Catharanthus roseus) and Bra z i I i an pepper (Schi nus terebi nthi fol ius) (Table 9 3) . within the disturbed vegetation, open sandy areas are dominated by a mixture of sand pine scrub species, most notably, sand live oak, jointweed, pawpaw (As imina reticulata), fetter bush, prickly pear cactus, Palafoxia feayi, and tread softly (Cnidoscolus stimulosus) (Table 3). MANAGEMENT PROCEDURES In the stated objectives for the management of the property, there are major responsibilities for the longterm preservation of the vegetation, wildlife, and soils, plus the area's natural resources. In this role, the following comments are reasonable judgements as to the management "state of the art", so that the preserves will be sufficiently protected for the future and not just short-term realities. Assessment of impact and management recommendations are based on field observations, comparison of past records, and a review of pertinent literature. Fire Management Fire has a necessary historical role in the perpetuation of sand pine scrub and maintaining its diversity of vegetation. Man's efforts to suppress fires and the development of firebreaks provided by human activity (i.e., roadways) have created the need for investigating prescribed burning programs to maintain sand pine scrub. Maintenance of sand pine forests fit a general classification scheme where high intensity crown fires occur only once in the lifetime of sand pine or about every 30-60 years I, 10 (Harper 1915, 1927; Webber 1935; Laess1e 1958, 1967; Christensen 1981) and have virtually defied man I s control efforts (Johansen and Cooper 1965; Hough 1973). Plow-lines are ineffective and actions of people, equipment and tools on the ground are usually futile. Due to the potential devastation of these types of wildfires, attempts at fire suppression have been the norm in F10r ida for more than 30 years. The unpredictable nature of these fires, their infrequent occurrence, and the lack of information on conditions favorable for planned ignition in scrub habitats, have not allowed for the application of prescription burning. Except where sites were totally mechanically prepared and treated as slash burns as in the Oca1a National Forest, to date, there are only a few examples of prescribed management fires that imitate a control crown fire in sand pine scrub communities (Cooper 1972) (which are found in central and southern F10r ida /~ dominated by pinus c1ausa var. c1ausa). winter prescribed fires h a v e bee nus e d e x ten s i vel y wit h laU c h s u c c e s sin the Choctawhatchee sand pine communities (which are found in northern Florida dominated by pinus c1ausa var. immuginata), as the understory fuels associated with this community are light and produce low intensity fires at this time of the year (Cooper 1972). However, wildfires continue to be the rule and literature on 'n sand pine scrub is limited. t. a1. (1987) successfully burned two separate sand pin rub preserves in Boca Raton using a modified <; 11 fuel model to develop an effective prescription for burning sand pine scrub under controlled conditions. The results of these contrQ11ed burns suggest that an effective, safe means exists to ---.--.----- l:?_u~!!.-_ sand pine scrubs in a developed landscape, prov iding thi.s option_~s available without smoke managpm~nt proh1pms and it wea ther cond i-t io.ns_ .dic..t..ak-PL.e.s.cI: iption bUl;niD5iJ-....oL-the Quantqm Park scrubs is possible. Management options for these two preserves range from a decision 1) to do nothing and let nature take its course; 2} to manage for the maintenance of a viable scrub ecosystem, which implies the natural biota, or 3} to focus management on the needs of one or more species. The decision to emphasize ecosystem or species management depends on the entity responsible for management, type of preserve, management objectives, area of the preserve and the nature of the surrounding lands. -X--Within the sand pine scrub preserves of Quantum Park. the management objectives should focus on 1) maintenance of normal ecosystem processes which include the perpetuation of endemic scrub plants and animals, 2} the conservation of local soil - characteristics which support the vegetation; 3} maintenance or - .--- restoration of normal hydrologic conditions; and 4} the - prevention of establishment of exotic species. Prior to the formulation of a step-by-step approach for the maintenance of these two preserves, it has been decided that each preserve will be divided into several smaller components in order -----------.-- to provide mixed stands of different ages. Based on the life , 12 history characteristics of the sand pine (pinus c1ausa) and rosemary {Ceratio1a ericoides~;-;:;;=~~ year burn ~been adopted for this study. This was based on the specific mortality traits of sand pine (senescence at 59-69 years) and rosemary (senescence at 29-39 years). To further age each preserve, tree core data was gathered from randomly selected sand pines scattered throughout each preserve (Table 4). Using this data, the scrub community of each preserve was divided into definable tracts that will be used to maintain the ecological diversity of the scrub (Figures 4A and 4B) . FUEL MODEL The chaparral/high pocosin/mature shrub model (NFFL Model 4) (Anderson 1982), was considered suitable as a base for developing a fuel model for the sand pine scrub communi ty in central and south Florida (Table 4). NFFL Model 4 presupposes a brush/shrub fuel understory six or more feet high, flammable foliage, a nearly continuous secondary overstory, with heavy loading of live and dead fine wood y mater ia1 s. Except for the more scattered understory, this is very similar to the sand pine scrub of the Quantum Scrub and seemed likely to be accurate in predictions of fire behavior in these fuels. Unlike some of the western brush types, which can usually be burned quite successfully under less than extreme conditions (Wright and Bailey 1982), sand pine has been virtually impossible to prescribe burn, and rarely burns except under the most extreme conditions (Cooper 1972). Prescription parameter development for a sand pine scrub 13 burn in southeastern Florida was based on a number of restrictive conditions relating to each scrub site: both preserves are surrounded by local or large scale development, preserve #1 is adjacent to a proposed city park, and preserve #2 will be surrounded by industrial or commercial lots and possib1~ a hotel --"- to the north. For permitting purposes, the stagnation index~as -.~ required to be below 7 (Florida Department of AgrIculture -1-9'76). Environmental parameters used to establish fire behavior predictions needed to provide for a reasonably intense fire in order to ensure that the sand pine scrub fuels would burn, yet be of moderate enough nature to be relatively certain of having acceptable fire behavior and smoke conditions. The following ranges of prescription parameters will be used in the scrub model: midflame windspeed of 3-7 mph; wind direction easterly- southeasterly; relative humidity 45%-69%; 1 hour dead fuel moisture < 11%; live woody fuel moisture 25%-75%; dry bulb temperature 75-85 of; and cloud cover < 19%. Values outside of the indicated ranges were also tested in the model but found to be unacceptable (Doren et. al. 1987). Fuels like the chaparral, which contain highly volatile compounds (we considered sand pine scrub such a fuel), require more preparation for prescribed burning than other fuel types (Wright and Bailey 1982). Because of the maximum spotting distance of 0.4 miles (0.64 km) and a Probability of Ignition of 79, some site preparation will be considered necessary in order to ensure a successful burn and protect the values at risk. , 14 SITE PREPARATION Three to four weeks prior to each burn, 10-29 m wide strips around each proposed bu rn site will be cr ushed us ing a sma II empty, roller drum-chopper (Model SL-7, Marden Manufacturing). One pass over the vegetation, with drums set parallel to each other, will be sufficient to produce a light slash, without appreciable soil disturbance or fuel compaction. A narrow (2-4 m wide) fire lane will be established around each preserve prior to each burn in order to prevent the.Rorsibility of a fire escaping / i into adjacent development lots. ~Of the sand pines within the chopped area will be dropped into the site to prevent spotting and to create hot-spots to help prepare a seed bed and open areas. Approximately 10-l5 days will be required without rain in order to dry out the crushed fuels sufficiently and reduce fuel moisture to prescribed levels. Within Preserve #1, the dry prairie/pine flatwoods areas will be burned separately from the canopied areas of scrub. Due to the nature of the dry prairie, it may be necessary to herbicide some of the grass pre-burn in order to stimulate the seeding of scrub species from the existing adjacent ridge. The sand pine fingers will not be regularly burned for at least 20 years except in areas now dominated by bahia grass. The most southern finger has been invaded from the west by bahia grass, nut sedge, and Ceasar's weed. These three species indicate that soil conditions may not be suitable for ~ongterm scrub survival since bahia grass will most likely out-compete '2 :3 4. l5 \, early scrub colonizers. In an effort to eradicate these troublesome species, areas of bahia grass will be herbicided and then mulched with hay or other suitable materials in order to increase fuel loads. The area will then be burned and a thin layer of scrub top soil will be broadcast over the burned areas. This should help the establishment of scrub species. Since these species are scattered over other areas within the scrub fingers, herbicide without mulching will be used on a local scale. The entire area will be seeded with sand pine which can be purchased through the Division of Forestry. Small scrub oaks and other nursery grown stock will be planted to form small islands within each of the fingers. Since the oldest trees occur in the northeastern corner of the sand pine scrub of Tract #1, the interior core of the oldest trees will be left standing for the burn. The sand pine around the fringes will be dropped in place after the area is roller chopped (Figure 5A). The remaining areas will also be chopped, however, no sand pine will be felled. This will allow seed input from the trees left standing as a result of seed release following the fire. Tract 2 will be roller chopped in a similar fashion to that of Tract 1. Two small islands of vegetation will remain standing with no mechanical alteration. The other areas will be roller chopped and the sand pines dropped in place (Figure 5A). In order increase diversity and to prevent the unaltered areas from S ignition during the burn, these areas will be watered by a 16 temporary sprinkler system at least one day pre-burn. This will increase the water content of the vegetation and make it difficult to ignite. Burning will occur between the months of December and February, following a wet month. If drought conditions prevail prior to the scheduled burn and the drought index is high, it should be postponed until conditions favor a controllable fire. The exact firing pattern of the burn will be decided by the burning agency (i.e., Division of Forestry, private firms, or local government) on the day of the burn. Head fires will be used were applicable to simulate the fire behavior (and effects) of naturally occurr ing fires, and to ensure as complete a burn of the vegetation as possible. All existing structures (i.e., boardwalks, fence posts, etc) that may have been constructed within the preserve at the time of the burn should be protected by herbiciding in advance of the burn and then raking down to mineral soil to remove debris from around the structures. This would reduce the fine fuels necessary to carry a ground fire. Since the site is currently being utilized as a relocation site for gopher tortoise and Florida mice, all burrows should be ~ flagged prior to roller chopping. If the preserve is fenced at the time of the burn, access should be made to the closest point 7 of entry by removing a section of fence to reduce damage to the remaining unburned areas and reduce soil disturbance. This can be coordinated with the on-site property association and the City of Boynton Beach. 17 Preserve #2 was also divided into 2 separate burn areas (Figure 5B) based on the natural contours and the existing disturbed areas within the preserve. Each burn site will be roller chopped in a similar fashion as Preserve #1 so that small islands of standing vegetation remain (Figure 5B). All sand pine on the margins of each tract will be dropped in place to prevent spotting in nearby vegetated areas. The fuel model and prescription used on Preserve #l will also be utilized for these burns. A temporary watering system will also be utilized for those areas that will not be burned. BURN SCHEDULE The following burn schedule will be utilized for the sand pine preserves at Quantum Park: Preserve #1 Tract # 123 Preserve #2 Tract # 1 2 Year 1988 1993 1998 2903 2008 2013 2018 2923 2028 2033 2038 2043 2948 2053 2058 2063 x x x x x x x x x x x x x x x x x x x x x x x The burn schedule was design to fit the existing age distribution within each sand pine parcel. The sand pines within Tract #1 of preserve #1 average about 30-35 years of age. Since this is the 7 ~ <1 10 fI IJ. l8 oldest portion of the scrub on this ridge, burning will occur in 20 years when the trees begin to reach senescence. Some of the older trees will be left to reach old age without the effect of burning. Seeding into the burned areas will occur from the existing margins of the scrub. Tract #2 will be burned in app rox imately 30 years when the trees reach matur i ty. The dry ~ prairie/pine flatwoods community will be burned every 5 years in order to stimulate new growth of herbs and grasses for local gopher tortoise populations. Areas within the prairie that are invaded by scrub species will be excluded in the following burn year. This will promote the development of scrub islands within the dry prairie system. The exact areas to be excluded in each subsequent burn will be decided by the City Forester or a private consultant prior to the prescribed burn. Sand pine within Preserve #2 range in age from ll-37 years with an average age of 19.5 years. Since no age specific distribution exists within this preserve area, the site was randomly divided to be burned on a 30 and 59 year rotation, beginning with tract #l of preserve #2. Tract #2 will be burned in the opposite rotation sequence (50 and 30 years) to allow for ecological diversity for local wildlife and plants. AGENCIES AND MATERIALS FOR BURNING Prior to each burn, a permit for burning will be obtained from the city forester. The burning will be coordinated with the city fire department who may be able to assist with fire protection equipment at the time of the burn. The State Division 13 cY'\ DOY 19 of Forestry will be contacted to disk existing fire lanes or to create new lanes depending on the conditions of the surrounding fuels and vegetation. If used, all fire plowing will be kept to a minimum depth (3 to 6 inches). The burn will be conducted by a private agency such as Forest Resources Management, 1528 Hendry Street, Fort Myers, Fl. 33901. Depend ing on the weather conditions on the day of the burn, the Florida Highway Patrol will be notified about possible smoke problems on I-95. Crew size and equipment will be determined by the agency conducting the burn. The estimated cost, based on 1988 figures, (SCRvlo AR€Cl.) for the above work will be about $8,000.00 for burning 10 acre blocks. The cost for burning less acreage may be slightly less, however, mobilization costs will be very similar. The above cost estimate includes any changes necessary to the burn plan, chopping the site, coordination with local and state agencies, man-power to conduct the burn, and permit acquisition from city and state agencies. The cost, based on 1988 figures, for burning the dry prairie will be about $l,500 to $2,000 for coordination, permits, and on-site burning. If burning turns out to be an unacceptable means for maintaining the existing scrub, due to smoke management or excessive explosive fuels, then mechanical means such as roller chopping will be utilized. This alternative method will require an empty roller chopper that will bend and break the vegetation near ground level, causing minimal soil disturbance. The use of a water filled chopper would cause severe soil disturbance which 20 could effect the longterm survival of these scrubs. The chopped . vegetation would then be removed from the site to allow scrub regeneration. Since most of the seed trees would be removed, these areas could then be seeded wi th sand pine by using the methodology utilized in the Ocala National Forest. Mechanically seeding some areas and not other would provide scrubs of various age classes, a benefit for longterm survival of many of the scrub animals. ~ Implementation of the above management plan will require the financial commitment from the local property association and the commitment by the City of Boynton Beach. In contrast to the above scrub management plan, approximately 1.3 acres of ruderal vegetation within preserve #2 14, should be immediately altered to allow the establishment of scrub - vegetation. These previously disturbed areas along the west edge -- of the site should be herbicided, mulched as described above and -- burned. A thin layer of scrub soil could then be scattered over the burn areas and then the area seeded with sand pine. - Prescribed burning would require the formation of a sandy fire break between the existing scrub and the ruderal vegetation. Burning should occur when the winds are out of the east to prevent smoke management problems on the interstate highway. This would force the flame front to the west, away from the sand pine scrub vegetation. Once the disturbed areas have been burned, sand pine seeds should be broadcast and slightly trenched into the sand about 2 21 inches. Other trees such as sand live oak could also be planted in these disturbed areas to simulate oak thickets which could be utilized by scrub jays as suitable nesting sites. Observations from other scrubs indicate that oak thickets with as few as 5 trees have been utilized as nesting sites by scrub jays. Two /) small oak thickets will be planted within the disturbed areas. Each thicket will be planted with 5 field grown sand live oaks which range in height from 5-7 feet. The trees will be placed in a pattern to produce a dense canopy required for nesting. ~ The burning of the ruderal vegetation within Preserve #2 would require a permit from the City Forester and coordination with the City of Boynton Beach fire department. EXOTIC PLANT REMOVAL One of the most serious threats to any native plant community in south Florida is the invasion of exotic vegetation. Exotics can modify normal ecological processes or relationships, including predator-prey and herbivore-plant relationships, nutrient and energy cycles, and soil-building and erosion processes. It has also been shown that the general stability of Florida's natural communities is also reduced. Brazilian pepper (Schinus terebinthifolius) and punk tree (Melaleuca quinquenervia) do occur within the preserve areas. An on-going treatment program was initiated on the 20 May 1987 by treating the base of each shrub or tree with herbicide (Garlon I~ 4) . The eradication process will be extended to all non-scrub (- species throughout the preserve areas in order to reduce unwanted 22 seed banks which may affect the long-term survival of the scrub community. The above management plan provides a step-by-step program to fulfill the requirements of the Development Order and the Treasure Coast Reg ional Plann ing Counc i 1 . Modi f i cat ions to the above plan may be in order as new information becomes available concerning the fire ecology of the sand pine scrub community. 23 Figure 1. Location of Preserve #1 and Preserve #2 within the Quantum Park project, Boynton Beach, Florida. '\ ,'".l.,) " ."'_.....-~. ,... .~- ~~ --- ( .~ i-."- .,.:: 10 " I: . , ~ Preserve #2 a ~.- ~D1:7 % .-k r:.! ()~ f\ ::'"};[}O . ~~:=fl" A~j '\ J::J 110 \.r t'C._ _.._ _ Figure 2A. 24 Aerial scrub, 'w i t h i n photograph showing areas dry prairie, and the dry Preserve #l. of sand pine retention pond " -.'0" \ , ':'-.0. ".""",f ....... ~...., "" 0'''' .( " ,'t'i f<:' "'--. ~.~ ,.;.I:'., r~ ." ,.. " I t . ~,;,c. ~. "'t J.(~:~"J ~t ~~J'or\ . r'!;"~'j ~ ..,~ ,.' ,,,) ~ '.f " .j. t ..Ir.'/~;.:; . " ,,~. ";.. ' . I' /' 'Jf.~., . " / .. ,;. 'I, f I, ... ,.. ( , ,. ~, '.~ \ '\r~'.!. ~r .1 J ,!04; .. , .. .~... l~ DRY PRAIRIE .'. '1J ..f,' " . ./ ~ ,.. .1' ., ,. . . ~\~f ~ ~ )., 11 .' -t;jl' ,,,,~,., .: "1 t,~ (.n. ~f . '~'~". l"~, .~~;.~\:" '.. 1 ti.~~~,~ . 19 /~~t~ ~~)~'~~{~ ..," I,. ~ 7~ l'" ft' ~\ < .r Ot..,;-': .... ..., .('~...~ \~ ......... ~::; ,:..,,-! L : ''',\", _. ....... Pr.".. _ f;.. ~&,.i~1 ~~~ ~I ~: ".J...t I . . ..:-!-~"JI ~ ~.,...., ~ ?:.~ {.~.:., :'.r~..; !,_ I. .p;'~ /'. <. {~... .. "" t ' f\.+, ~ '"f;. \i.r:-; " ~ It~ 1 :', .. t- r"'(I,!, 25 Figure 2B. Aerial photograph scrub and ruderal showing areas of sand pine vegetation within Preserve #2. Figure 3. Microsited Areas that support sand pine scrub . vegetat ion. 26 21 'f'igUt:e 41\. BU~n ttactS to~ p~ese~~e '1. .' ." ~ r" ,. . ~ . . t"" . r(:;;~~ J~f, ~~.:~~; :: .~ '.' ~ ~,t .," ,,' ) I ,~" .j.. f' ..,}Y,I';":' , ,.;' "/ ",' I. /,,'J; ,:,.~ " , Ii I k.r ~, ':'[ J ~. ,I ~-j /. ~>... I i ,.. ~r .. ;' t, ." , . ,<"':...:: 2'" , .~ f't ~J; .~ . 'I ~ .f" ). . r.- '" ;~~ ,. ~ .,.t }\.\! _'~"~ ," ,ti"~' .: ~ ~~ ti (.~. ~, ~,.,."'i"_~""JJJ .', ... ~" .,.}}"t"\' .. A'\~~'~;~" . .,i;",,, 'J(~-. ;,41". :J; ~~ I "! 1.'1"':;;"/'1 . ~:~:~' \:~., 0:--' !~ TRACT 3 . .~.. ,- p~ ~.\ . ,r ~"'. ~'.. fY.l''', ' :~ _.r. (~.._ I.. .~~~:; :.;! 'f{ ..t ~f":"! ,,:....,1. $'~' t"',~...;'/ . .W! ;" ~.~. . -;,ff. r.r':.' "~\ .i "...; .' ,f.. ~.' ?,', "'5 t.J .i << .. "'~ \ ~t... ... ". I f~ ~' ii. , ,. . 1.. It .. ,."",i~ ----- .~. ....\...' ----..-..-.----------- 28 Figure 4B. Burn tracts for Preserve i2. ~, " Tract 1 l lJ ( (. , '; .. If... k Figure SA 29 Areas within Preserve tl that must be roller chopped (diagonal lines) prior to the prescribed burn. ~ r . ,. ~ .. Roller chop Trees up r~). ...... t ..... , ... ~. ,. " ;;. r ., . '{..i 11'",,, " I 60,.'-1 , , r ' 'I/. ,~ ,.., .f. ... ,.. 'r ,'''~ .. .. i. .to , .,' 'I.~' i ..' I,~. :....:. . . .t' .l'1. <I .....": ......... ,,~ 't \,',..tf: . "1:;;' Scrub 1""",~,,~,:, ~.~t!,. ..,'"it l;,"':./ ,''''to " 'f I . ~ . Roller chopped Trees down ... { ~,' . (':' .,.. ../'I .;, _I -, !', 0- f .. f' ~. r;');~..~ .. .. ''''r~ ... f-- ~.:.. ;~ naltered Scrub , ..,,~ '"i..1 "" .....r... . ~ .' ~'.' ~ " ., of . '... ,,-, , :f',:;. 4 "1- " ,." , ,~ it, J .~ ,\o~...:. ,-.... ~ . "'" '.., r, , r~({ _ Unaltered Scrub Figut:e 5B. 30 ~<eas ~ithin p<ese<ve 12 that must be <olle< chopped (diagonal lines) prlo< to the prescribed burn ...i~ ~ ,; ...... 'l."~ke,. . ., J" :t .V'~~\~, \ ,'( '" .;~' ,; I' '.~' ~:1J' :<..;.. ,,:r :,. ,a ~; " ~.,.; j"''' 't.i!" ' ( ,'. :~, ."\ ". ' '.. i.: I .t.t.. ~. <_.. ..v." !o'\..~,.,... ...,', ..~ '~... ,.,;"",...../ ::.i;:..~' "'0"1." . .....'.. ..~".i}.::......... fo ...' ,<;" ;'.$ .,.r'.;:'':''':''' ~ ' .... ~;:!':~,,\ ""I~.~{l\i\\"";'" ~i. '7-- t-1.~ ~ ;~;';!~:, ,f' 1 ,...r ~, ~ji,;' .~~.. ".~ ',';J /,' :.:i: l'.'.' ~.., ~'.,I\: "..' ,', f' ! ,f', I .....1 ,~" .... , ~,. -:-.',~' ~ .. ):> ': '~.H'> , ~) 00 ~ . ~~f~~"~~,i.,[~.~~~"~:~::, .. ~ . "'l~;'''' :~-,,,,.,)~ .;. ... . ,\~. ,,:', . " ' .~~,... . ,. ,..,-' . ' I ",.., ~.I:':':"~"" '. ',... b '.. "\b';1 ,.~ , ' r "'f,'\\t,~:"', !:.;. ~/'':J':~' !l;'" .. ,;\ " \,K~!-4~:' A~;:}J. ~.\ L' ...,~ ': ~ .' ~ ':;0;;", " .:;!.~\~ .". ... n,l ~ ',' ':-<v' .~ ," .,'0:.' .. ." . JFlt;" .... $'.... II: ... ...;,; . ".t--.:r ;:, . ).....;,:=,.. ~ ....' 'w .... I ''''. '. ..' .. ,).' ..". ;'" ...,,, .:1, .~ "_' ",. . lo' t 1"... ,\' '.." ~!\" "J"i-" t,,'~..i''';<: <,\~.... ,~~")~ .;. ,~. \...~. ,:;. {..i:t {. Ro11er chopped Trees up ": Una1ter Scrub .. '. '~' ... una1tered scrub ~.',,~. ,.t" '" \\, ),;1'4' "g,(I' : Unal tel scrub Ro 11 er choppe( Trees down Una1tered Scrub Ro11er chopped tre ,..,",::,;t' ," ' "J~, 31 Table 1. Checklist of the vascular flora for the Sand pine Preserve il at Quantum Park, Boynton Beach. Scientific Name Common Name Trees Acacia auriculaeformis Ficus aurea Ilex cassine Melaleuca quinquenervia pinus claus a Pinus elliottii Sabal palmetto Earleaf Acacia Strangler fig Dahoon holly Punk tree Sand pine Slash pine Cabbage palm Shrubs Asimina obovata Asimina reticulata Befaria racemosa Ceratiola ericoides Conradina grandiflora Gelsemium sempervirens ~lex glabra Licania michauxii Lyonia ferruginea Lyonia lucida Palafoxia feayi Quercus chapmanii Quercus geminata Quercus myrtifolia Rubus trivialis Sabal etonia Schinus terebinthifolius Serenoa repens Vaccinium myrsinites Ximenia americana PawPaw PawPaw Tarf10wer Rosemary Scrub mint Yellow jassamine Gallberry Gopher plum Rusty lyonia Staggerbush Palafoxia Chapman's oak Sand live oak Myrtle oak Blackberry Scrub palm Brazilian pepper Saw palmetto Huckleberry Tallowwood Herbs Abrus precatorius Ambrosia artemisiifolia Andropogon virginicus Aristida gyrans Aristida spiciformis Aristida stricta Asclepias curtissii Aster tortifolius Balduina angustifolia Bulbostylis ciliatifolia Cassia chamaecrista Roasary pea Ragweed Broomsedge grass wiregrass Bottlebrush threeawn wiregrass Curtiss milkweed White-topped aster Yellow buttons Hair sedge Partridge-pea Cassia nictitans Cassia occidentalis Cassytha filiformis Catharanthu5 roseus Cenchrus incertus Centrosema virginianum Chrysopsis scabrella Commelina erecta Conyza canadensis Crotalaria rotundifolia Croton glandulosus Crotonopsis 1inearis Cuthbertia ornata Cynodon dactylon Cyperus haspan Cyperus planifolius Cyperus retrorsus Dalea feayi Dichanthelium dichotomum Dichanthelium sabulorum Digitaria serotina Diodia teres Eclipta alba Emilia fosbergii Eupatorium capi1lifolium Euphorbia milii Euphorbia polyphyl1a Euthamia minor Froelichia floridana Galactia regularis Gelsemium sempervirens Gnaphalium pensylvanicum Hedyotis procumbens Helianthemum nashii Heliotropium polyphyllum Heterotheca subaxillaris Indigofera hirsuta Lechea cernua Lechea deckertii Liatris chapmanii Linaria canadensis Mol1ugo verticillata Momordica charantia Opuntia humifusa Paspalum notatum Paspalum setaceum Phytolacca americana Pityopsis graminifolia polanisia tenuifolia Polygala incarnata P6lygonella ciliata Polygonella fimbriata Wild sensitive plant Cof fee -senna Love vine periwinkle Sand spur Butterfly-pea Goldenaster Dayflower Dwarf horseweed Rabbit-bells Croton Rushfoil Roseling Bermudagrass 32 Nutsedge Blanket crabgrass Poor Joe Cupid's shavingbrush Dogfenne1 Crown-of-thorns Spurge cottonweed Yellow jassamine Cudweed Innocence Heliotrope Camphorweed Hairy indigo Blue toadflax Indian chickweed wild balsam apple Prickly-pear cactus Bahia grass Thin paspalum Pokeweed S il kgrass Procession flower Wireweed Sandhill wireweed 33 polygonella gracilis pOlygonella polygama polypremum procumbens portulaca p ilosa pterocaulon virgatum Rhynchelytrum repens Rhynchospora megalocarpa Richardia brasiliensis Schrankia uncinata Scoparia dulcis Selaginella arinicola Setaria geniculata Seymeria pectinata Sida cordi folia Sisyrinchium solstitiale Smilax auriculata Solanum americanum Solidago chapmanii Solidago stricta Spartina bakeri Spermacoce assurgens Spermacoce verticillata Stipulicida setacea Tillandsia recurvata Tillandsia usneoides Tillandsia utriculata Trichostema dichotomum Urena lobata Vitis munsoniana wi reweed Jointweed Rustweed pink purslane Rabbit tobacco Natal grass Scrub sedge Sensitive briar Sweetbroom Sand spike moss Foxtail grass Blue-eyed grass Sawbriar Common nightshade Goldenrod Goldenrod Sand cordgrass Ball moss Spanish moss wild pine Forked blue-curls Caesar weed wild grape 34 Table 2. Tree core data for Preserve Il and 12. (Sampling within Preserve #1 was based on four 29 x 29 m quadrats. Sampling within Preserve 12 was based on a random walk in an east-west direction along animal survey lines). Preserve I Quadrat I Density Avg. Avg. dbh age 1 1 6 18.7 18.6 1 2 18 l4.5 l7.8 1 3 l3 15.7 16.3 1 4 9 25.6 21.8 1 Total avg. 46 18.6 l8.3 2 Total avg. 19 24.1 19.5 35 Table 3. Checklist of the proposed 14 acre sand pine preserve. Scientific N"ame Common Name Trees Acacia auriculaeformis Brassaia actinophylla pinus clausa Pinus elliottii Earleaf acacia Schefflera Sand pine Slash pine Shrubs Asimina reticulata Ceratiola ericoides Conradina grandiflora Ilex glabra Licania michauxii Lyonia ferruginea Lyonia lucida Palafoxia feayi Polygonella polygama Quercus chapmanii Quercus geminata Quercus myrtifolia Saba1 etonia Schinus terebinthifolius Serenoa repens Vaccinium myrsinites Ximenia americana PawPaw Rosemary Scrub mint Gallberry Gopher plum Fetterbush staggerbush Pa1afoxia Jointweed Chapman's oak Sand live oak Myrtle oak Scrub palmetto Brazilian pepper Saw palmetto Huckleberry Tallowwood Herbs Andropogon virginicus Aristida gyrans Asclepias curtissii Bulbostylis ci1iatifolia cassytha filiformis Chamaecrista fasciculata Cnidoscolus stimulosus Croton glandulosus Cyperus retrorsus Dalea feayi Dichanthelium sabulorum Eupatorium capillifolium Euthamia minor Euphorbia polyphylla Galactia regularis Hedoyotis procumbens Helianthemum nashii Heterotheca subaxillaris Broomsedge grass Wiregrass Curtis milkweed Hairsedge Love vine Partridge pea Tread softly Croton Nut sedge Dogfennel Spurge Milkpea Innocence Camphorweed 36 Lechea cernua Lechea deckertii Lupinus diff.usus Opuntia humifusa Paspalum notatum paspalum setaceum Phytolacca americana Pityopsis graminifolia Polygonella ciliata Polygonella gracilis Polypremum procumbens Rhynchelytrum repens Rhynchospora megalocarpa Selaginella arenicola Setaria geniculata Seymeria pectinata Sida cordifolia Sisyrinchium solstitiale Smilax auriculata Solidago stricta Stipulicida setacea Ti1landsia recurvata Vitis munsoniana Nodding pinweed Blue lupine Prickly pear cactus Bahia grass Thin paspalum Pokeweed Silkgrass Wireweed Wireweed Rustweed Natal grass Scrub sedge Sand spike moss Foxta il grass Blue-eyed grass Sawbriar Goldenrod Ball moss Wild grape Table 4. Comparison of fuel model parameters for Sand pine scrut7 and NFFL Model 4. parametersa' Sand Pine Fuel Mddela NFFLa 1 Hour (dead) fuel load (tons/acre) 10 hour (dead) fuel load (tons/acre) 100 hour (dead) fuel load (Tons/acre) Live herbaceous load (tons/acre) Live woody load (tons/acre) 1 hour f ue 1 <Surface area to volume ratio, ft2/ft3) Live woody surface area to volume ratio (ft2/ft3) Depth of fuel bed (feet) Heat (BTU/ft2) Moisture of Extinction (%) wind adjustment fact~r 5.01 4.01 2.00 0.99 5.91 5.91 4.91 2.90 9.00 5.91 2009 2090 2099 8 8909 29 0.59 2999 6 8909 29 9.69 aAll measurements are given in standard units in the science of fire behavior. Conversion to metric would not be appropriate for the purposes of this paper.