The melaleu­ca is van­ish­ing from Loxahatchee

By Olivia Balsinger

Through­out the warmer months, its cream-col­ored flow­ers offer a stark con­trast to the green leaves, on its curvy branches.

But with­in the Ever­glades of South Flori­da, this Aus­tralian import, the melaleu­ca, does not belong.
The melaleu­ca, a tree orig­i­nal­ly from Aus­tralia and New Guinea that arrived in South Flori­da about a cen­tu­ry ago, pro­vides shel­ter but very lit­tle else in food or resources.

It is a pest, an inva­sive species resis­tant to fires and oth­er threats.

Yet the Arthur R. Mar­shall Lox­a­hatch­ee Nation­al Wildlife Pre­serve in Boyn­ton Beach, Flori­da has wiped out 85
per­cent of its Melaleuca.

Accord­ing to Lisa Jame­son, an inva­sive species biol­o­gist at Lox­a­hatch­ee, the suc­cess of the decrease in melaleu­ca is due to pro­grams instilled by the park to con­trol the main inva­sive species. While the plant orig­i­nal­ly cov­ered about 94,000 acres of land with­in the Lox­a­hatch­ee, Jame­son said that it would like­ly cov­er less than 6,000 in the next year and a half.

Author­i­ties are attempt­ing to lim­it the spread of melaleu­ca by quar­an­ti­ning stands of trees, and apply­ing vary­ing her­bi­cides, includ­ing melaleu­ca psyl­lid and melaleu­ca snout wee­vil, that kill seedlings. The main­te­nance con­trol from melaleu­ca has been so suc­cess­ful that it now cov­ers less than five per­cent of the area

“Since I arrived in 2008, we have been work­ing on try­ing to elim­i­nate or real­ly min­i­miz­ing the amount of inva­sive species by putting them under main­te­nance con­trol,” said Jame­son. “We work on each inva­sive indi­vid­u­al­ly until it is under con­trol. Melaleu­ca has been a great suc­cess so far.”

Melaleu­ca, how­ev­er, proves to be one of the more suc­cess­ful sto­ries of inva­sive species with­in the Everglades.
Pro­tect­ing the reserve is extreme­ly crit­i­cal right now because the U.S. Fish and Wildlife Ser­vice leas­es the land from the South Flori­da Water Man­age­ment Dis­trict. In order for Lox­a­hatch­ee to keep the refuge and land, the four pri­ma­ry inva­sive species, melaleu­ca, Brazil­ian pep­per, Aus­tralian pine and old world climb­ing fern, must be under main­taince con­trol. The stip­u­la­tion is that all four species must have less than one per­cent cov­er­age by 2017 in order for the land to keep its ownership.

Jame­son believes that per­haps the most dif­fi­cult inva­sive plant to con­trol will be the climb­ing fern because of its ease in spread­ing and tak­ing over areas. It will be almost impos­si­ble to elim­i­nate this plant as eas­i­ly as the oth­er three by 2017, said Jameson.

The treat­ments for elim­i­nat­ing old world climb­ing ferns in a refuge are dif­fer­ent than those used in a for­est. How­ev­er “there is a lot of research going on right now to devel­op bio-con­trol, though dif­fer­ent chem­i­cals that can kill spores in soil and also kill the plants,” said Jame­son. “The park is try­ing dif­fer­ent treat­ments with fire and drown­ing out the old world climb­ing fern.”

“Unless we nuke every­thing, we are scared we will not meet the 2017 dead­line,” she con­tin­ued. “But if we did that, there would be too many native dead plants, which real­ly makes the issue of inva­sives a two-sided coin.”

Inva­sive species are the sec­ond biggest threat to bio­di­ver­si­ty next to loss of habi­tat, accord­ing to Jame­son, which is why so much time and effort has gone into their elim­i­na­tion. One of the main rea­sons as to why they can per­sist in habi­tats that are not their own is because they may not encounter nat­ur­al enemies.

“Exot­ic plant species thrive in South Flori­da. Also, we are so mobile in this era, which is why non­na­tive species growth is accel­er­at­ing at the rate it is going at,” she explained.

In fact, accord­ing to Lar­ry Perez, a sci­ence com­mu­ni­ca­tions inter­preter at Ever­glades Nation­al Park, about 40 exot­ic species arrive each month on the shores of the Unit­ed States.

“Some inva­sive plants and ani­mals cool look beau­ti­ful. They could just be in the wrong place at the wrong time,” said Jameson.

One exot­ic species that has been a high­light of media atten­tion and which many not be ordi­nar­i­ly cat­e­go­rized as beau­ti­ful is the Burmese python, which has been mul­ti­ply­ing and may now num­ber as high as 180,000 with­in South Florida.

One means of attempt­ing to stop the spread of the inva­sive species is through leg­is­la­tion. For instance, fed­er­al laws now pro­hib­it pythons from com­ing into the coun­try to be sold as pets with­out giv­en explic­it permission.

Once they are here, their costs can be enor­mous. Accord­ing to Jame­son, about $5 bil­lion annu­al­ly is spent by the Unit­ed States through tax­es to try and tame the amount of native species. Out of this amount, $2 bil­lion a years spent to keep the inva­sive species that have already spread more con­tained in cer­tain areas.

“[Every­one in Amer­i­ca] needs to be con­cerned with the inva­sive species prob­lem in the coun­try because it is all of [our] tax mon­ey,” said Jameson.

Jame­son came to Lox­a­hatch­ee in 2008, but she has held jobs with the Nation­al Parks Ser­vice that have tak­en her to all of the states and posts on both the east and west coast of the Unit­ed States.

Jame­son grad­u­at­ed with a com­pre­hen­sive wildlife degree and then worked part-time for the fed­er­al for­est ser­vice in tim­ber man­age­ment. She then went to work for park ser­vices and the Mis­souri Depart­ment of Con­ser­va­tion until becom­ing a per­ma­nent employ­ee for the Nation­al Park Ser­vice 26 years ago.

“My inter­est in inva­sive species began about mid­way through my career,” Jame­son said. “I had a real­ly good teacher who was the nation­al man­age­ment spe­cial­ist, and in her class I learned about inte­grat­ed pest man­age­ment issues, which includ­ed bats, birds and all pests regard­less of if they were inva­sive or not.”

Jameson’s career was stim­u­lat­ed through edu­ca­tion, and now she tries to make oth­ers aware of the prob­lem of inva­sive species with­in the Ever­glades through the same mea­sure. Edu­ca­tion, accord­ing to Jame­son, is one of the eas­i­est and most ben­e­fi­cial ways to edu­cate the pub­lic about the poten­tial dan­gers asso­ci­at­ed with non­na­tive species.

Jame­son once took a group of stu­dents into a for­est where melaleu­ca trees had very much tak­en over the area.
“I stopped every­body and I said lis­ten… and that’s what they heard—nothing,” explained Jame­son. “None of the stu­dents could hear what used to be able to be heard…and that may like­ly have some­thing to do with these invasives.”

Jame­son also encour­ages every­one to learn what plant and ani­mal species are native and what are non­na­tive. “If you choose to get an exot­ic pet, find out about its habi­tats, if it is com­pat­i­ble with the new envi­ron­ment. It is just impor­tant to edu­cate yourself.”

“The best way to con­trol and even­tu­al­ly stop the spread [of exot­ic species] is pre­ven­tion,” said Jame­son. “If we can pre­vent it now, we will not have the infes­ta­tion later.”

(Four pho­tographs of the inva­sive species cour­tesy of the Uni­ver­si­ty of Geor­gia Cen­ter for Inva­sive Species and Ecosys­tem Health)