Heteranthera zosterifolia is an aquatic plant 30-50 cm tall. The stems are long, slender, and covered with fine hairs.
It can be easily identified by its bright green star-shaped leaves arranged in a spiral pattern around the stem.
Heteranthera zosterifolia Classification
- Domain: Eukaryota
- Kingdom: Plantae
- Phylum: Tracheophyta
- Subphylum: Angiospermae
- Class: Monocotyledonae
- Order: Commelinales
- Family: Pontederiaceae
- Genus: Heteranthera
- Species: Heteranthera zosterifolia
- Common Names: Stargrass
Nativity and Distribution
Star grass is native to South America. It is mostly found in:
- Brazil
- Argentina
- Uruguay
- North America
- Australia
- Oceania
Physical Characteristics
- Leaves: Alternate, bright green leaves with entire margins
- Stems: Herbaceous. Can grow 30-50 cm tall.
- Flowers: Small, floating, blue or pale purple flowers
- Roots: Water roots
Heteranthera zosterifolia is a perennial marsh plant that grows 30-50 cm tall. It is easily recognized by its bright green star-shaped leaves arranged in a spiral pattern around the stem.
Stems are slender, fleshy, 30-50 cm long and fairly pubescent. They are bluish-green with slight purple hues towards the base. The leaves are flat, alternate, lanceolate, 1-2.5 cm wide, and 5 cm long with entire margins.
They have a soft, fleshy texture with a slightly waxy surface. The upper surface is bluish-green while the lower surface may have an additional purple or black tint.
The leaves form a unique arrangement along the stem, each emerging at a different angle, giving the densely p a star-like appearance.
Flower heads are borne in clusters at the end of the stems. They are 6mm across with 6 petals, and pale blue to white with darker patches in the middle and grow in 2-10 groups.
The seeds are winged and enclosed in a capsule of 8-14 seeds.
Reproduction, Dispersal, and Life Cycle
- Life Cycle: Perennial
- Seeds: 8-14 seeds enclosed in a capsule
- Climate: Grows well in subtropical areas that are hot and humid
- Dispersal: Water, wind, and water birds
H. zosterifolia behaves as a perennial aquatic plant and reproduces by seeds and plant fragments. The seeds germinate in the mud and rapidly produce shoots and side shoots towards the surface, forming dense covers on water bodies.
The seeds can also be spread by the wind, contaminated pond water dumped in other waterways, and water birds.
The plant can also propagate by fragments that break off from the parent plants. The broken parts are moved to different locations by birds, floods, and boats.
Similar Plants
- Heteranthera reniformis
- Heteranthera rotundifolia
- Heteranthera multiflora
- Limnobium laevigatum
Uses
Star grass is grown as an ornamental pot plant. It is also used as a decorative plant in aquariums for its lush greenery and beautiful flowers.
Impact on Farms and Environment
As an aquatic plant, star grass provides food and habitat for various organisms like fish, frogs, and other microfauna. It can also help improve water quality and reduce nutrient runoff by absorbing excess nutrients from the water. Additionally, its root system can prevent erosion of shorelines in shallow water areas.
However, H. zosterifolia can become invasive in new areas competing with native aquatic plants for resources and space. This can lead to decreased native biodiversity and ecosystem alterations.
Its dense growth can also impact water flow in diverse water bodies and impede boating, fishing, and other recreational activities.
Control
- Mechanical control: Hand pulling
- Chemical control: Herbicides like glyphosate and flumioxazin
Hand pulling can help eradicate small infestations. Ensure that you remove the stems and root fragments and dispose of them properly.
Herbicides approved for aquatic use including glyphosate and flumioxazin can provide better control for larger infestations. The applications are typically done by spot spraying or injection.
When using herbicides, always read the label and follow all the instructions and safety requirements. If you need more information, consult an expert.
Lead Editor for Insight Weeds.