Alligator weed (Alternanthera philoxeroides) is a problematic aquatic weed that invades wetlands rivers lakes and canals. This fast-growing plant can form dense mats that crowd out native vegetation and disrupt aquatic ecosystems. Alligator weed is native to South America but it has been introduced to many other countries including the United States where it is considered an invasive species.
Alligator weed is a perennial plant that can grow up to 2 meters tall. The leaves areAlternanthera philoxeroides and they are arranged in a spiral pattern on the stem. The leaves are green with a white or yellow margin. The flowers are small and white and they are borne in clusters at the leaf axils. The fruit is a small dry capsule that contains several seeds.
Alligator weed reproduces vegetatively and by seed. The plant can produce large numbers of adventitious root buds that can develop into new plants. The plant can also reproduce by seed but this is less common. Alligator weed seeds are dispersed by water and animals.
Alligator weed can be very difficult to control once it becomes established. Physical removal is often the best method of control but this can be difficult because of the plant’s ability to produce new plants from fragments. Herbicides can be effective but they must be applied carefully to avoid harming non-target species.
If you are concerned about alligator weed infesting your property it is best to take preventive measures to keep the plant from becoming established. Remove all plant fragments from your clothing and equipment after spending time in areas where alligator weed is present. Do not move soil or water from infested areas to non-infested areas. And be sure to dispose of alligator weed plants properly so that they cannot spread to new areas.
What is alligator weed’s scientific name?
Alternanthera philoxeroides
What native country is alligator weed originally from?
Argentina
How did alligator weed come to the United States?
It was brought over in the 1800s as an ornamental plant.
What does alligator weed look like?
Alligator weed is a perennial herb that can grow up to six feet tall.
The leaves are opposite oblong and have toothed margins.
The white or occasionally pink flowers are born in clusters.
Where can alligator weed be found in the United States?
Alligator weed is found in the southeastern United States.
What kind of habitat does alligator weed prefer?
Alligator weed prefers wet habitats such as marshes ditches and riverbanks.
How does alligator weed spread?
Alligator weed spreads by fragmentation.
When the stem or root breaks off a new plant can grow from the piece that broke off.
Alligator weed also spreads by rhizomes which are underground stems that can put out new roots and shoots.
What kind of damage does alligator weed do?
Alligator weed crowds out native plants and changes the structure of habitats.
It can also clog waterways and make them impassable.
Alligator weed is also toxic to livestock.
What is being done to control alligator weed?
Mechanical methods such as mowing digging and chopping are used to control alligator weed.
Chemical methods such as herbicides are also used.
What are some natural enemies of alligator weed?
The alligator weed flea beetle is a natural enemy of alligator weed.
The larva of the flea beetle feeds on alligator weed and can reduce the plant’s growth.
What are some problems with using herbicides to control alligator weed?
Herbicides can kill native plants and animals as well as alligator weed.
Herbicides can also pollute water and soil.
What are some alternative methods of controlling alligator weed?
Some alternative methods of controlling alligator weed include using covering to prevent the plant from getting sunlight using organic herbicides and using alligator weed for biofuel.
What is alligator weed’s economic value?
Alligator weed has some economic value because it can be used for biofuel but it mostly causes economic damage because it crowds out native plants and can clog waterways.
What is alligator weed’s environmental impact?
Alligator weed has a negative impact on the environment because it crowds out native plants and changes the structure of habitats.
It can also clog waterways and make them impassable.
What is alligator weed’s effect on human health?
Alligator weed is toxic to livestock but it is not known to have any direct effect on human health.
