Hydrilla is an aquatic plant. It is generally considered to contain only one species, Hydrilla verticillata. It is also known as H. asiatica, H. japonica, H. lithuanica, or H. ovalifolia. Some features are listed below.
- leaves
Its leaves are 2-4 mm wide and 6-20 mm long. They have pointed tips and saw-toothed margins. They have a rough texture because there are spines on the leaves. They are usually green, while the upper leaves are slightly yellow. The reason is that the sun can somehow bleach the leaves.
- stem
The Hydrilla stem is very thin. It is only 1/32 of an inch wide. However, it can grow to a length of 30 feet. It usually branches near the surface of the water.
- flowers
Its flowers are divided into two classes: male flowers and female flowers. The male flowers can be white, reddish or brown. The female flowers are usually white. Hydrilla can be monoecious, meaning both types of flowers on one plant, or dioecious, meaning only one type of flower on one plant.
- Clothes
Hydrilla is a submerged plant. It can grow in almost any freshwater habitat such as springs, lakes, swamps, river ditches, etc. It can resist a salinity of up to 7%. Its optimum growth temperature is 20-27 o C. It has low light compensation, indicating the ability to grow in low light conditions. This makes it a competitive plant because it can grow in deeper water and starts photosynthesis earlier in the morning.
- Four ways to play
- Fragmentation: Fragmented pieces can sprout into a new plant. The only requirement is that it has to contain at least one node.
- Tubers: Tubers are also viable. Each can produce up to 6,000 new ones.
- Shoots: If the shoots break off and settle in the sediments, they can also grow into a new plant.
- Seeds – Unlike most plants, this is the least important way for hydrilla to reproduce. Perhaps this is because seed production is a good option for long-distance dispersal, which is often not the case.
- risks
As mentioned above, hydrilla can easily spread to new areas. Due to their good growth capacity, native aquatic plants will be shaded until they are eliminated. Apart from reducing biodiversity, it is also detrimental to fish, because the thick layers of hydrilla can alter chemistry and oxygen levels. It also greatly slows down the flow of water and severely interferes with navigation. Therefore, we have to take measures to control its growth.
