Johns Lake Vegetation Mapping

Johns Lake Vegetation Mapping

      The vegetation in Johns Lake has been studied to understand native growth and invasive species progression and overall health. The work is conducted by Florida Fish and Wildlife Commission (FWC),
managed out of the Northeast Regional Office, under the direction of Lake County Regional Biologist, Nathalie Visscher ( FWC used to conduct the study about every
five years, using outside contractors. With recent budget changes, they now conduct a mapping study
every year with internal staff. Since Johns Lake is in Lake and Orange Counties, Lake County takes
the lead.
     In late May of this year, FWC sent teams to complete the mapping for 2017. The data gathering typically takes anywhere from three to five 5 days. They utilize as many as four boats at a time, using
GPS locations, probe poles, depth soundings, and visual observation to collect the information about
the current status of the vegetation growth or decline. They will compile the data into a detailed map
to show the vegetation changes from year to year. The results should be published soon and when it
is available, we will provide a link or copy for your review

Plants for the Lakefront

Plants for the Lakefront

Mary Louise Grable

      For some reason many lakefront homeowners have the erroneous concept that the perfect landscape should include a lakeshore comprised entirely of sand. There are numerous attractive plants that benefit wildlife, help control erosion, protect water quality and should be included in the landscape plan.
     Shoreline vegetation that is beneficial should not be removed simply to construct a beach. In fact certain trees and endangered plants cannot be removed. Plants that are native to the area greatly reduce or eliminate the need for the use of fertilizers and pesticides. It is okay to remove invasive nonnative vegetation such as torpedo grass, but some of the shoreline needs to be replaced with native plants. There is an excellent website that provides substantial information on restoring the lakefront. Go to Seminole County’s website to find all you need to know about the many aspects of the process.

Panicum hemitomon

An emergent plant known as Duck Potato or broadleaf arrowhead has lance shaped leaves and provides showy white flowers with three petals. The flowers appear on stalks that are taller than the leaves. It is a Florida native and grows well at the shoreline or in the water. The tubers are edible and were once a staple for the indigenous people.

Maidencane, a native Florida grass, is excellent for shoreline stabilization. It is a perennial grass growing 2 – 5 feet in height and is found only in freshwater. Although it can get out of control, it is easier to manage and should not be confused with torpedo grass (Panicum repens) which is a nonnative invasive species and almost impossible to control.

Sagittaria lancifolia
Ponetrderia cordata

Pickerelweed is an attractive Florida native plant found in shallow freshwater and often used as an ornamental plant in water gardens. It is easily recognizable by its beautiful violet blue, uncommonly white, flower spikes which bloom almost the entire year. It is common, extending by rhizomes to the height of 2 – 4 feet. Bees and butterflies are attracted to the flowers, ducks and people eat the seeds and the leaves can be boiled like greens. The plant provides good cover for birds, fish, reptiles, amphibians, insects and
swimming mammals.
It is doubtful that cypress trees were once found on Johns Lake, but currently several lakefront landowners have been successful in growing them. These unique trees dominate the wetlands and are the most tolerant of floods of all Florida trees. The deciduous, often Spanish moss laden conifer has been part of the landscape for thousands of years. It is excellent as wildlife habitat, for flood control and maintaining water quality.

Bald cypress grows mainly in wetlands over many years and may reach over 100 feet.
Its leaves are linear and spread on branchlets. Pond cypress (Taxodium ascendens) does not grow as large and favors depressions in pond and lake margins. Its leaves are awl-shaped and press against branchlets. Some botanists consider them separate species; others as variations of the same species. Both are unique and attractive trees.

Taxodium dictichum

In addition to the plants identified in the above article, other commonly found native plants are shown below. There are may species available from some of our local aquascpaing
nurseries. They are all beautiful additions to your lakefront landscape, and you will be amazed at the number of birds, butterflies, fish and mammals that will be visiting your new and Florida Native shoreline!

Fire flag

 (Thalia geniculata)

Soft rush

(Juncus effuses)

Swamp lily

(Crinum americanum)

Golden canna

(Canna Flaccida)

Blue flag iris

(Iris Virginica)

Scarlet hibiscus

(Hibuscus coccones)

Grass Carp

Grass Carp

Mary Louise Grable


      Grass carp are nonnative fish imported from Asia for the control of higher invasive aquatic plant species such as hydrilla. They are a more cost effective method of control than using herbicides
or the use of mechanical means. A combination of the methods is the most effective in trying to control hydrilla. Estimates for using grass carp to control hydrilla are $15 per acre as opposed to $100 – $500 per acre using herbicides. Mechanical harvesting is even more expensive. 

      Grass carp are one of the largest members of the minnow family. Their life span is approximately 15 years. It takes about 6 months to a year for the fish to become effective in controlling vegetation. One of the few species of fish that eats plants, the grass carp does not eat all varieties of plants. It is important that overstocking does not occur. The grass carp found in Florida lakes have three sets of chromosomes (triploid) and are certified to be sterile. The largest triploid found in Florida was 15 years old, measured 56 inches in length and weighed 75 pounds. 

     These fish have large scales with a silvery to dark gray back, lighter golden sides and white belly. The body is round with a broad head. The fish are stocked in Johns Lake. Sometimes they are caught while fishing for tilapia or catfish. If a grass carp is caught, it is required that it be released

Brevard County’s Indian River Lagoon

Brevard County’s Indian River Lagoon

J. Martin Davis, P.E.

….. Is it the ghost of Christmas Future for Johns Lake?

     In November 2016 voters in Brevard County, by a margin of over 63 percent, approved a half-cent sales tax to provide $302 million over a 10 year period to clean up the increasingly polluted waters of the Indian River Lagoon. This water body has been increasingly threatened over the past 5 years by fish kills, algae blooms and increasing levels of nitrogen and phosphorous. About two-thirds of the money will go toward removing muck from the bottom of the lagoon, estimated to be just under 5 million cubic yards. Another $62 million will be spent for septic system removal and sewer plant upgrades to supplement the loss of the septic systems.

     At the risk of being overly alarmist, could there be parallels between the Indian River lagoon and Johns Lake? Population growth and the unending appeal of living on a body of water insures that development will continue on every available developable parcel on Johns Lake, just as it is occurring on the Indian River Lagoon. And, as we’ve explored in past Cattales issues (June 2016), several of the older communities on Johns Lake are on septic tanks, albeit the more recent development have been on sewer systems. We’ve also looked at the water quality parameters published by Florida Lakewatch since water sampling for Johns Lake began in 1989. This data indicated that the water quality parameters, including the all important nitrogen and phosphorous levels, have remained relatively stable.

A clue to this serendipity may lie on the graph of Johns Lake historical water levels, included below, which was also included in the last issue of Cattales.

No Data Found

Johns Lake Levels 1959-2016

    You will note that lake levels appear to reach very low levels at approximately 20 to 25 year intervals, as evidenced by the low lake levels that occurred in 1980 and 2001 where the low water levels were around elevation 86 or less. It’s difficult to visualize the impact of this lake level until one sees, as is shown by the included aerial photo of Johns Lake, circa 2002, just how much of the lake bottom is exposed by these drought events.

     But this fluctuation of water level in Johns Lake is actually a very beneficial and helpful attribute of our lake. See, Johns Lake does not have springs or streams that provide a constant source of water into the lake. Rather our lake relies on rainfall, runoff and groundwater levels to replenish and maintain lake water levels. As such, our lake water levels are quite variable, as variable as the Florida weather. 

     But this is actually a major benefit in terms of maintaining water quality. During these periodic dry spells and the ensuing drop in water levels, large swaths of the lake bottom are exposed to the drying effects of sun and wind on any accumulated muck that may have been deposited on the lake bottom, drying out and blowing away the muck that otherwise might remain and accumulate indefinitely. If the Indian River Lagoon had these fluctuating water levels, it is unlikely $200 million would now be spent on muck removal.
So, we’re golden, right. With this built-in environmental lake bottom vacuum cleaner we’ve got, we’re good
to go …right? I think not so fast. 50 years ago the environmental pollutants that now affect the Indian River
Lagoon were by and large unidentified, or at least ignored. Let’s keep our collective heads up lest we suffer
the same fate.

17th Annual Johns Lake Holiday Boat Parade

17th Annual Johns Lake Holiday Boat Parade

Sunday, December 17th @ 6:00pm

     This year is the 17th Annual Johns Lake Boat Parade! The event will be held on Sunday, December 17th at 6:00pm. Come out and decorate your boat with lights and join in the fun! Last year we had a record 42 boats in the parade, and many spectators at the public boat dock on Lake Blvd. in Winter Garden, and on the shoreline!

     All boats participating should gather a few minutes before 6:00pm on the southeast corner of Johns Lake. NOTE: THIS IS A NEW MEETING LOCATION. The lead boat will start the parade by blasting an air-horn several times. All boats should follow in-line and slowly head east. The parade route will follow the southern, eastern, and northern shores of Johns Lake (from Twin Waters in Orange County to Magnolia Bay in Lake County, where parade ends). The parade will take about 2 hours to complete. Please see the map below.

     If this is your first time decorating your boat for a parade, here are a few tips: Christmas lights run on 120v AC and are designed to operate from your home electrical current. To operate lights on your boat, you will need to purchase a DC to AC power inverter. Power inverters are available at most auto parts stores, Wal-Mart, and Harbor Freight. Power inverters convert your boat’s 12v DC power to 120v AC. Inverters do have a limit as to how much power they can generate from your boat’s DC battery. Inverters are rated by watts; the more watts the inverter can handle, the more lights you can put on your boat. Most power inverters above 150 watts will need to be connected directly to your boat’s battery terminals to provide full power as 12v outlet plugs (cigarette lighters) are power limited by a fuse.

     Use of LED lights provide the ability to power many more lights than incandescent lights. A 300 watt power inverter connected directly to your battery could power over 600 LED lights as opposed to 60 incandescent lights! Be careful though, as some units will overheat if too much load is placed on them. 

     Test your lights for a period of time before the parade starts. Make sure you use UL approved outdoor lights as the lights on your boat may get wet and you do not want to cause a fire or shock someone on your boat! If you do not live on the lake, you can view the boat parade from the public boat ramp located on Lake Blvd. (north shore of Johns Lake, off of Hwy. 50 at the Lake/Orange County line). The parade should be passing the ramp at approximately 7:00-7:30pm. If you have any questions about the boat parade, please call Ann at 407-701-8033 for details.