Hobbies And Interests
Biology
Water lettuce is a floating plant with oval, green, hairy leaves that are arranged in rosettes. They have a velvety feel and are ribbed. Water lettuce does indeed look like an open head of Bibb lettuce. The flowers rise from a leaf axil. There's one female flower and several male flowers inside a whitish spathe, or a sort of hood, about four inches long. The male flowers are at the top of the spathe and the female flower at the base. The flowers appear in April. The plant rises about 10 inches out of the water.
Reproduction
A reason that water lettuce is so invasive is that it reproduces by runners. It reproduces so quickly, in fact, that newer plants are pushed out of the water onto the banks. It has even been seen, in dry seasons, rooted in wet soil. Moreover, the plant also produces many seeds, and the seeds are spread through the water.
Conditions and Range
Water lettuce needs lots of nutrients and direct sunlight. It can be found in around 17 states in the U.S., in Puerto Rico and the Virgin Islands. Even though it's a tropical plant, it also grows as far north as upstate New York.
Environmental Impact
Water lettuce can form such dense mats that they can block sunlight and cause oxygen depletion of the water. This leads to death of fish and other types of vegetation because they have no access to sunlight. If possible, the water lettuce should be removed from the waterway, spread out on the ground to dry out and die and then be thrown in with compost. Since the roots float and don't extend into the bed of the body of water, the plant can just be pulled out by hand.
As Aquarium Plant
If water lettuce has to be grown in an aquarium, the aquarium has to be large because of the plant's rapid growth. It must have a source of bright light, and the temperature should be from 72 to 82 degrees Fahrenheit.