MCISMC COGONGRASS CONTROL GEOGRAPHIC STRATEGY



marion county invasive species management council

Cogongrass Control Geographic Strategy

Linda Conway Duever, Coordinator

1/30/07 Draft

This is a living document intended to be repeatedly refined and updated to reflect current situations. Clarifications, corrections, suggestions, and other constructive criticisms are welcome – and are especially solicited where they help “fill in the blanks” indicated by bracketed remarks.

Note that this is not the entire MCISMC strategic plan. Other documents address educational programs, treatment methods, legal issues, etc. and other species of concern. This one is just about the distribution of cogongrass and where control efforts should be directed.

Key action items have been italicized to serve as the basis for a “to do” list. Potential partners are suggested in bold type.

Mapping

Thanks to the cooperation of Mike Jenkins, with the support of Dean Jue and others, the Florida Natural Areas Inventory (FNAI)’s invasives program is using Marion County as a pilot project for their new online/interactive geographic information system (GIS) at . This system incorporates interactive mapping features that allow users to view location data with plant photos, then enter additions and updates online. We need to refine the fields and protocols to optimize both the educational and data-entry aspects of the interface and the usefulness and accuracy of the data. We hope to incorporate features from TNC’s Weed Information Management System (WIMS) [citation and URL] to create a system that will function much like the Southwest Exotic Mapping Program (SWEMP)’s system [citation and URL].

Cogongrass (Imperata cylindrica) datapoints currently currently visible on the FNAI pilot project site include locations on and around Marion County public lands and infestations detected during the 2005 aerial survey conducted by The Nature Conservancy (TNC) in cooperation with the U.S. Forest Service (USFS) and the Florida Division of Forestry (FDOF). Data from Ocala National Forest, the Cross Florida Greenway, Rainbow River State Park, Silver River State Park, county parks, and all FDOF, MCRPD, St. Johns River Water Management District (SJRWMD), and Southwest Florida Water Management District (SWFWMD) lands is included. We also need to assure that the U.S. Navy is conducting proper monitoring and control programs on the Pinecastle Bombing Range (within Ocala National Forest) and that their data is on our maps.

Although the public land managers tell us that we can assume that virtually all surviving stands on their properties have been mapped, future followup surveys will be necessary to confirm that unmapped stands treated previously have actually been eradicated. We will have to see that all public lands are properly monitored and that data on the FNAI maps is updated and kept current.

Most of the occurrences immediately adjacent to these managed areas are on this map too, but surveys for nearby offsite infestations have not been as rigorous as those for onsite stands. We will need to work with public lands managers, their citizen support organizations, and neighboring community groups to assure that all stands in proximity to vulnerable natural areas are indeed mapped, tracked, and eradicated.

The TNC aerial survey was conducted as part of a regional survey for high-priority invasive species. The plane flew a grid from SR 50 near Orlando to just north of Gainesville and recorded all observed cogongrass stands. Since the bright chartreusey yellow-green color of this grass is distinctive from the air, it can be safely assumed that they detected practically all stands more than a few feet across on this survey grid. We need to evaluate what we can safely extrapolate about the number of occurrences between transects.

The Marion County Transportation Department Roads Division (MCTDRD) now has maintenance crews entering GPS points for cogongrass infestations along county road ROWS in the course of their work. These are being entered into the county’s GIS, where they are periodically printed out on county road maps. Some road crews have proven more diligent about this than others. We need to work with MCTDRD to assure that all occurrences on and/or adjacent to county roads in all parts of the county, including the heavily infested southwest corner, are mapped.

The Florida Department of Transportation (FDOT) has provided some data on cogongrass infestations along state highway ROWs. FNAI has contributed additional FDOT ROW cogongrass locations collected during Dicerandra cornutissima surveys near the I-75 Cross Florida Greenway land bridge. We need to confirm that all of these are on the current FNAI map. (This federally endangered plant species occurs in patches intermixed with cogongrass stands along that portion of the interstate corridor; we therefore need to assure carefully integrated management of these two species on the FDOT ROW, on adjacent Office of Greenways and Trails lands, and on other nearby properties. Reports indicate that the mowing schedule currently used to control cogongrass is too frequent for proper development of the Dicerandra plants ) We need to evaluate the completeness of the state highway dataset and persuade FDOT to supply the locations of all remaining locations on or adjacent to state road ROWs.

Clay Electric Cooperative has agreed to have their crews record GPS locations of cogongrass stands they observe. We need to make arrangements for their data to be routed to someone who can enter it in the proper GIS database. We also need to follow up our preliminary discussions with Progress Energy, Ocala Electric, and Sumter Electric Cooperative and request that they collect similar data and route it appropriately.

The county’s two largest timber companies, Rayonier and Plum Creek, are beginning to map cogongrass infestations on their lands and contribute datapoints for our maps. We need to maintain communication to make sure that we get complete data on these timberlands. Since timber harvesting procedures tend to spread cogongrass, the infestations on timberlands are generally more extensive than those elsewhere. We therefore need to set up our GIS database to accept polygon vs. point data for these lands. (As our GIS emphasis moves from assessing distribution patterns to planning and tracking treatment results, we will need to use polygon data for other occurrences too. Point data is adequate for most of the county now because we are dealing with a preponderance of small patches.)

We need to identify and involve other large landowners.

Interested citizens have contributed sketch maps, road intersection information, or parcel numbers identifying many cogongrass locations. We need to enter these citizen-contributed records into our database and develop a protocol for tracking whether occurrences reported by non-professionals have been confirmed to be cogongrass stands.

We are currently working with two online GIS databases, FNAI’s and Marion County’s.

Marion County’s award-winning interactive GIS [bib ref and URL] allows citizens to easily zoom in on any spot in the county and overlay data layers for aerial photography, topographic maps, property boundaries, roads, water bodies, etc. and link them to landowner names and addresses. Because of the aerial photo options and the inclusion of every county road and property line, it permits the user to find familiar locations easily.

Hundreds of cogongrass locations recorded by county road crews have already been entered into the Marion County GIS system, which is set up to display them as point locations represented by little green grass-clump icons that actually look like cogongrass. We envision involving the community in our war against cogongrass through putting this overlay data online and showing the icons turning from yellow (representing treated/managed stands) to brown (representing dead/eradicated infestations).

We now need to figure out how to best utilize and interrelate these two powerful online GIS database and establish protocols for transferring data between them. We also need to write text describing our program to go on the Marion County GIS site and link it to the new MCISMC site.

Distribution Patterns

The maps currently available show several major concentrations of cogongrass in Marion County.

The largest area of infestation is that centered on the rapidly growing Silver Springs Shores residential development area southeast of Ocala [need a map here]. It includes stands on the Cross Florida Greenway and extends in patches eastward across the Ocklawaha River encompassing Silver River State Park and including the inholding-fragmented western fringes of Ocala National Forest. A finger of intensive infestation reaches southward along CR 317A from Moss Bluff to SR 42.

We have another major concentration along the northern boundary of the City of Ocala [need another map]. This problem area is generally south of CR 326, but extends slightly to the north along US Hwy 441, where North Marion Rock [ck name]’s quarries are heavily infested with both cogongrass and kudzu.

There is another cogongrass concentration in the southwest corner of the county, extending from the Rainbow Springs - Dunnellon area eastward to Ross Prairie.

There are significant cogongrass infestations all along the Cross Florida Greenway. Two factors come into play here. One is that excavation work preparatory to the ill-conceived and now defunct Cross Florida Barge Canal created vast areas of disturbed land vulnerable to cogongrass invasion along this corridor. The other is that the sheer amount of edge inherent to this linear natural area exposes it to special risk of invasion from beyond its boundaries. This is of even greater concern because the Cross Florida Greenway adjoins and connects so much highly sensitive state and federal land. (This situation, discussions with land managers, and the fact that cogongrass has expanded on OGT-managed Price’s Scrub since state purchase indicate that we must assure that OGT gets urgently needed increased funding for and/or more outside assistance with invasives control.)

Whereas the current maps appear to indicate the general patterns of cogongrass infestation in the southern part of Marion County realistically, we are skeptical of the impressions conveyed by the maps for the northern part of the county. The scattered stands depicted for the northwest corner seems generally realistic in relation to on-the-ground observations, but the larger number of occurrences shown in the northeast corner is a result of much more thorough USFS surveys.

The most worrisome area is in the timberland region in the north-central part of the county, centered on Fort McCoy and the N-S CR 315 corridor. Our current maps show few cogongrass stands far off the highways here, whereas we hear complaints about numerous infestations. Though Plum Creek reports that the cogongrass on their lands is largely restricted to patches along access roads, there may be more extensive infestations on timberlands in this vicinity than are apparent. Since cogongrass spreads readily in response to timber harvest, and timberland management practices tend to weaken rather than eradicate it, there may be significant suppressed populations that have not been detected by aerial surveys. Even if cogongrass has not moved far away from the roads here yet, the extent of the roadside infestations makes this area appear to be severely at risk for rapid cogongrass expansion. We need to evaluate the cogongrass situation in the Fort McCoy area and work with Plum Creek, Ft. McCoy community groups, and other landowners to develop a local control plan.

Strategy

MCISMC’s geographic strategy for cogongrass control is based on Robin Lewis’ “bull’s eye” approach to preventing exotic invasion of restoration sites (Randall et al. 1997) and Steven Dewey’s “Attack Your Weeds Like a Wildfire” guidelines (Carpenter and Murray 2000). Lewis speaks of treating critical areas vulnerable to invasion as the center of a bull’s eye and maintaining concentric control buffers around them. Dewey explains that, in both fighting wildfires and controlling invasives, you must 1) build a fireline; 2) eliminate spotfires; 3) protect critical areas; and 4) control the main outbreak. In the discussions that follow, we add two concepts to this analogy: 5) prevent blowups; and 6) conduct mopup operations.

Several fortuitous circumstances make MCISMC’s county-based weed management area ([refs]) particularly appropriate to this landscape. One is that Marion County is basically uplands (cogongrass habitat) more or less surrounded by wetlands (not cogongrass habitat) (Figure [ ]). Another is that the swaths of land along the county lines are generally relatively cogongrass-free. It is therefore logical for us to establish control lines along the county boundaries and work with the adjoining counties to extend cogongrass-free zones to a line along the natural wetland buffers.

Our strategy calls for separating cogongrass concentrations with ever-widening cogongrass-free zones. We intend to promote this “divide and conquer” approach at all scales, from statewide programs down to the neighborhood or tract level. This is a good generic weed control plan, but it especially appropriate for Marion County’s populations of this sexually reproducing species. Scientists have found evidence that our cogongrass populations are not producing anywhere near as much viable seed as they could with increased cross-pollination (Schilling et al. 1997). Keeping stands separated could therefore prevent major explosions of cogongrass reproduction and much more extensive spread via windblown seed. (Taking such reproductive concerns into account could be added to Dewey’s wildfire analogy as “Prevent blowups!”) Since even a 15-20 ft buffer precludes over 90 percent of pollen transfer (Lewis 1979), maintaining separation between stands is important even at the microscale. Isolating populations also reduces their genetic diversity and hence their ability to develop herbicide resistance and other adaptations that might complicate control efforts.

Priority Protection Areas

Native Upland Groundcover

Preventing invasion of existing high quality native upland groundcover is our most critical priority, with such sites ranked in the following order: 1) lands already under ownership or easement providing for permanent management protective of groundcover integrity and biodiversity; 2) public lands where the groundcover is subject to current or future damage from logging, OHV abuse, or other severe machine disturbance; 3) lands proposed for preservation; 4) lands for which credible preservation plans have not been proposed.

Protecting damaged sites with high ecological restoration potential is a secondary priority. Such places would include ecological restoration project sites, such as the Church Lake and Delancy projects on Ocala National Forest, the Price’s Scrub Red Oak Woods, [others?].

Another secondary priority is protecting high quality native groundcover that could potentially be “rescued” from lands slated from development, such as that on the On Top of the World property or that associated with the Lake Diamond Golf Course in Silver Springs Shores.

Another is protecting our remaining remnant patches of red oak woods groundcover vegetation. Most of this has been severely degraded, but the little barely recognizable bits we have left along seldom-mowed fencelines and ROWS are extremely valuable as sources for seeds and transplants to enhance the biodiversity of restoration projects.

In all of the above situations, protecting areas likely to support rare plant species is most critical.

We should inventory, map, categorize, and prioritize all of Marion County’s native upland groundcover resources and couple plans for protecting them from cogongrass with strategies for assuring that those slated for preservation are properly managed and those slated for development are used as sources for ecological restoration materials.

Propagule Export Sources

It is essential that we promptly identify places from which cogongrass propagules are likely to be trucked to new invasion sites. These include rock quarries, sand mines, road materials depots, and hayfields. We should also examine sources of water used for fighting wildfires. We should assure that cogongrass is promptly eradicated from these sites and institute a program for monitoring them.

Critical Buffers

We will define critical buffer zones around native upland groundcover resources, potential propagule export sources, and lands at risk for rapid invasion and eradicate cogongrass from the inner edges of these buffers, then expand them outward with successive waves of treatment effort.

Lands at risk of rapid invasion would include planned timber harvest areas and other places where extensive shortterm soil disturbance is imminent. We will work with FDOF, USFS, timber companies, and private forest landowners to develop strategies for buffering timber harvest and site treatment areas. We will ask farmers, realtors, and developers to help us prevent invasion of lands they plan to clear. These strategies will have to include provisions for onsite control before and/or after soil disturbance as well as plans for establishing buffers.

Outliers

We will treat isolated cogongrass stands as high priority “spotfires”. We will endeavor to eliminate existing outliers early in our program, then institute procedures for assuring prompt response to newly discovered stands. Young stands are relatively quick and easy to destroy since they are small and do not yet have extensive deep root systems. Therefore, and because they may represent genetic material new to the neighborhood, recently established stands will generally be regarded as our highest priority outliers.

Control Lines and Zones

We will delineate control lines to serve as “firelines” and work to establish cogongrass-free zones behind them. Over time, this will create an effect like that you observe when you place a big chunk of melted-together ice cubes in a basin of warm water: areas of infestation will be separated and keep shrinking until they all disappear.

The following descriptions and Figure [map] indicate preliminary placement of these control lines. As we refine our maps, remove outliers, expand buffers around priority protection areas, and extend eradication efforts towards containment areas, we will draw more precise boundaries, create widening cogongrass-free zones, and define more control zones to further fragment and shrink areas of infestation.

The appropriate positions for the control lines will therefore shift as our program develops. We will review and redefine control lines annually as we update this strategic plan. This will enable us to produce maps illustrating our progress and post them on the MCISMC, Marion County GIS, and FNAI websites to encourage public participation.

We will consider a zone cogongrass-free when we 1) believe we have surveyed it thoroughly enough to have found all significant stands; 2) have encountered no evidence suggesting the presence of undocumented infestations; 3) have inspected all known infestation sites during the summer following the last treatment and found no visible evidence of viable cogongrass; and 4) believe that there has been no seed production in the vicinity for a year.

Fortunately, cogongrass seed viability declines rapidly after the first couple of months, so persistence in the seed bank does not appear to be a problem (Shilling et al. 1997). We will, however, operate under the presumption that overlooked sprigs and deep-rooted rhizomes will inevitably cause cogongrass to reemerge in many of these places in the future. Therefore we will maintain intensive monitoring programs in cogongrass-free zones for at least the first three years after “eradication” and remain permanently prepared to treat new outbreaks in these zones promptly. The period between apparent elimination of known occurrences through the next three years should be regarded as a “mopup” phase during which is critical to locate and destroy all remaining traces of viable cogongrass.

Central Florida Control Line

Following a suggestion from Kathy Burks, we plan to establish an east-west line across Marion County and promote it as a critical control line in the statewide war against cogongrass. Her idea was to create a cogongrass-free swath here, then extend eradication efforts northward from it to meet the control line being maintained at the Georgia border. She saw another effort pushing southward from this line to a containment area centered on the Polk County phosphate mining region.

It would be logical to begin the western end of this cross-peninsula control line where the Cross Florida Greenway meets the Gulf of Mexico, run it eastward along the northern edge of the Cross Florida Greenway to the Marion County line, then bring it north along the Levy-Marion line to CR 326.

The line will cross east-west across the center of Marion County. It will follow CR 326 from the Levy County line eastward to and across the Avatar Tract, then go east along NE 100th Street, then due east across Rayonier’s lands to Mud Lake in Ocala National Forest. From there it will run diagonally southeast across the Juniper Prairie Wilderness to the junction of SR40 and SR19.

We picture the line being extended eastward along SR 40 to I-95 through local, state, and federal scenic highway programs associated with the Florida Black Bear Scenic Byway, then continued to the Atlantic through Volusia County efforts.

We should ask the Marion County Citizen’s Coalition to coordinate maintenance of a cogongrass-free zone along the north side of 326 from the Levy-Marion Control Zone east to US 441 and ask Stavola to maintain it from 441 east to the Avatar property. We should insist that the agencies/organizations responsible for the Avatar tract promptly survey it for cogongrass and immediately eliminate any infestations north of 326. Rayonier will be asked to route this line across their lands and maintain a widening cogongrass-free zone along that corridor. OGT should make a priority of controlling cogongrass on this stretch of the Cross Florida Greenway. The Marion County Audubon Society may be willing to work with smaller private landowners to assure that the remainder of the swath from Avatar eastward to Ocala National Forest is kept free of cogongrass. USFS will be responsible for maintaining and expanding the control zone within the national forest.

Alachua-Marion Control Zone

We will establish another control line along the Alachua County line. This is particularly important because there are extensive infestations in southern Alachua County, whereas the adjoining portion of Marion County currently has only limited areas of invasion.

Alachua Conservation Trust has offered to contribute matching funds towards our next PTI grant for the purpose of helping Alachua County organize an invasive species management council and begin attacking cogongrass from this control line northward.

On the Marion County side of the line, we can readily eliminate the young infestations along the Price’s Scrub boundary and the one small stand on the north side of the NW Hwy 320 ROW. OGT should make a top priority of eradicating the Price’s Scrub stands. The Green family would probably be willing to organize adjoining landowners to address areas adjacent to the west side of Price’s Scrub. The Greenberg family might work with MCTDRD similarly to eradicate the stand along 320. Then we can work with the Simonton community to control the invasion east of I-75 and move our control line south to NW Hwy 320. After we treat a few more outliers, including those on or adjacent to the Smith ranch at the west end of NW Hwy 320, we can move the section of this control line west of NW Hwy 329 all the way south to CR 318. The Smith family might be willing to take responsibility for eradicating the outliers west of NW Hwy 329 and north of NW Hwy 318. It will take a more substantive effort to work with MCTDRD to control the linear infestations along NW Hwy 329 and NW 100th Ave Rd. The Shiloh Community Watch and/or the Shiloh United Methodist Church might take responsibility for the area north of Dungarvin Road (NW 193rd St). The Flemington park support group [correct name?] could be asked to work with the Flemington Community Watch, the local Boy Scout troop, and the churches in that community to address the infestations along NW Hwy 329 and NW 100th Ave Rd from NW Hwy 318 north to Dungarvin Road (NW 193rd St). Louise Courtelis, who owns Town and Country Farms, which lies between and NW 100th Ave Rd and I-75, might be willing to fund treatment in this area. The landowner currently developing a portion of the Orange Lake Overlook should be requested to eliminate the isolated infestation there; the McIntosh Seedings Garden Club might offer encouragement and/or participation. With the cooperation of MCTDRD and Clay Electric, the Orange Lake Veterans of Foreign Wars (VFW) post might be willing to eliminate the infestation at the intersection of US 441 and NW Hwy 318. (The slope under the powerline at the northeast corner of this intersection has valuable remnant red oak woods groundcover that should be protected.)

We need to survey the area between 318 and the south shore of Orange Lake from the 441 intersection eastward to the intersection of 318 and NE 199th St Rd, then develop a plan for eradicating the outliers in that area and quickly pushing that portion of the control line south to 316. The staff of the IFAS research farm [correct name?] on 318, where cogongrass research is conducted, might be willing to partner with a Citra community group to coordinate eradication of stands in and around Citra and between there and US 441. The Heubeck and/or Baldwin families might support efforts in this area. The Conservation Trust for Florida could be a partner here too, since they hold a conservation easement on part of the Heubeck’s Quail Roost Farm.

Levy-Marion Control Zone

We should work with FDOF (the agency responsible for Goethe State Forest, which parallels much of the Marion County line just inside Levy County), the Whitehurst family (who have extensive holdings in the northeast corner of Levy County), and other Levy County interests to create a cogongrass control zone along the Levy County line. We will encourage Levy County to look forward towards the establishment of an invasive species management council to carry these efforts ahead.

Inside Marion County, we will request that the Smith family take responsibility for the lands north of 318. John Rudnianyn, who owns 4,000 acres south of there, should be asked to work with other landowners to eradicate cogongrass from the area north of the 326 Central Florida Control Line, south of 318, and west of NW Hwy 325. We need to find a community group to manage the area from the 326 corridor south to 328.

Our current GIS maps show no cogongrass infestations south of 328 and west of US 41, but Harvey Markham of Romeo sent us a map indicating the locations of several outliers in the northern part of that area. (These will be added to the online database soon.) We need to find a Rainbow Lakes group willing to assure that that area remains cogongrass-free all the way to Goethe State Forest and the Cross Florida Greenway. OGT should be extra-cautious to keep cogongrass off the Cross Florida Greenway from Dunnellon westward.

Sumter-Marion Control Zone

Since the Withlacoochee River constitutes a cogongrass barrier along the Citrus County line and control efforts on the Marion County side of the river will be addressed through the Rainbow River Containment Area, there is no need to create a separate control zone along the Citrus County line. (We will nevertheless encourage establishment of a Citrus County invasive species management council.)

A Sumter-Marion Control Zone will be established to contain cogongrass invasion along the western end of Marion County’s southern boundary. It will run from the Withlacoochee River and SW Hwy 200 east to US 441.

At the present time, other than those FDOF has been tracking and treating on or very near Ross Prairie State Forest, our maps show no cogongrass in this zone south of SW Hwy 484 and west of I-75. (We are, however, aware of some on the I-75 ROW just to the north and suspect that that infestation may extend south into this area.) We should survey this area to determine whether or not it is already cogongrass-free and promptly treat any outliers found. We need to find a Marion Oaks community group to work with FDOF, SWFWMD, FDOT, and OGT to extend the control line north to 484, then push it north to 200, thus creating a cogongrass-free wedge between 200 and I-75.

We will find a community group in The Villages to take charge of maintaining a cogongrass-free zone from I-75 east to 441. We will ask them to initially secure the area from the county line north to SR 42, working with FDOT to eradicate the stands along this highway. We will ask this group to pay careful attention to the tiny triangle of land on the northeast side of I-75 in extreme northeast Sumter County and be certain that Sumpter County does not overlook any cogongrass problems there.

We will ask SWFWMD to help us persuade Sumter County to establish a cogongrass-free zone along the county line and push it southward.

Lake-Marion Control Zone

Because Marion County’s long Lake County edge includes three different types of landscapes, we have broken it into three control lines to be addressed by different types of partnerships. All along this line, we will need strong support from within Lake County. Therefore, working with the Lake County Conservation Council and the Lake Beautyberry Chapter of the Florida Native Plant Society to establish a Lake County invasive species management council is a high priority for MCISMC.

Lake Weir Control Line

We will look for a community group in the Lake Weir area to take responsibility for creating a cogongrass-free zone along the county line from US 441 to the Ocklawaha River and pushing it north to constrict the Silver Springs Containment Area.

Altoona Control Line

The Ocklawaha Valley Audubon Society might be willing to work with the Altoona Trail Riders and other Altoona community groups to establish a cogongrass-free zone from the Ocklawaha River east to SR 19, initially focusing on the area from the Lake County line north to SR 42, then working with USFS to push it northward to assure removal of cogongrass from inholdings and private lands adjacent to that portion of Ocala National Forest.

Lake George Control Line

Save Our Big Scrub will work with the Lake County Conservation Council to assure that USFS works in partnership with the U. S. Fish and Wildlife Service (USFWS, which manages Lake Woodruff National Wildlife Refuge), SJRWMD, and local organizations and community leaders to eliminate cogongrass between US 19 and the St. Johns River (including Lake George).

Putnam-Marion Control Zone

We have begun working with the Putnam County Environmental Council (PCEC) to establish a Putnam County invasive species management council and maintain a cogongrass-free zone along the Putnam-Marion border. Key partners in this effort will include Plum Creek, SJRWMD, the U.S. Army Corps of Engineers (USACE), and an Orange Springs community group to the west and USFS, OGT, and Save Our Big Scrub to the east.

Ocala Control Zone

We will ask the City of Ocala to assume responsibility for eradicating cogongrass within the city limits.

Containment Areas

In order to allocate our limited resources most effectively, we will establish several “containment areas”, inside of which cogongrass treatment will be a low priority for Phase II. Although we will continue to encourage cogongrass control in those areas and plan to institute active programs there in the future, we do not plan to devote substantial time or money to those formidable efforts during the 2006-2008 phase of our program. For now, we will direct our energies to areas where we can more effectively protect larger areas of the landscape.

Although MCISMC will only conduct limited outreach and neighborhood organization efforts in the containment areas during Phase II, we will urge landowners within the containment areas to cooperatively and strategically control stands that 1) pose a severe fire hazard to nearby property; 2) are subject to processes or activities likely to spread propagules outside the containment areas; or 3) are located on or adjacent to managed natural areas. We will encourage landowners to make use of our website information, organize their own control programs, and maintain communication with us. Our website will provide information on simple suppression and containment measures and promote these where intensive eradication efforts are not currently feasible.

During Phase II of our program, we will refine containment area maps to distinguish lower priority lands likely to be intensively developed over the next decade from higher priority places that have a reasonable chance of remaining unbulldozed into the foreseeable future. We will then make plans to address the higher priority portions of the containment areas in a future phase of our work.

Silver Springs

We need to define a boundary around a containment area encompassing the severely infested lands centered on Silver Springs Shores (Figure [ ]). Within and adjacent to this Silver Springs Containment Area (SSCA), we will work with DEP, SJRWMD, and OGT to develop strategies for protecting their lands and separating them from the SSCA with cogongrass-free zones. We will work with USFS, Save Our Big Scrub, the Florida Black Bear Scenic Byway, school and community groups, and Guy Marwick and other local leaders in the west-central part of Ocala National Forest to establish a control line along the east side of the heavily infested inholding-fragmented part of the forest and expand it west towards the Ocklawaha.

We will also work with Rayonier to develop a strategy for addressing their lands north of Silver Springs. They own 20,000 acres centered in that area and estimate that 20-40 percent of it has cogongrass on it. These 4,000-8,000 acres thus constitute the largest contaminated area in the county, but the populations have been suppressed so that the magnitude of the infestation is not readily apparent from aerial survey observations. Rayonier’s greatest concern is how aggressively cogongrass seizes control of sites on the “gumbo clay” soil common in this area. They have observed that it quickly forms a tight rootmat throughout the top foot of the soil and “takes over hydrology” here.

Ocala North

We will also examine the cogongrass concentration north of Ocala and define a containment area there. The limits of that area and the relative priority of the lands within it should take into account the boundaries of the county’s transfer of development rights (TDR) receiving area.

Rainbow River

On Top of the World (OTOW) has done an excellent job of limiting cogongrass invasion on their lands. We will work with OTOW to complete eradication on the northwest side of SE Hwy 200 and push cogongrass back towards the RRCA. There is a local native plant club (not a Florida Native Plant Society chapter) at OTOW that might take a leadership role in this. We will also work with Dr. Crayton Pruitt to create a control zone across his 9,000-acre Flying C Ranch east of Rainbow River. We need to identify a community group to coordinate cogongrass elimination from SE Hwy 328 south to the RRCA and southeast to the OTOW lands.

Treatment Site Prioritization

In view of the considerations discussed above, our first priority will be to eliminate isolated young stands in high quality native groundcover on lands committed to conservation.

Stands on propagule export sites or isolated young stands on lower priority native groundcover sites will fall into our second tier of priorities.

Older and less isolated stands on lower priority native groundcover sites, isolated young stands within the inner zones of critical buffers, and extreme outliers will be third-level priorities.

[Link to online bibliography at .]

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