Myriophyllum spicatum: Origins and Common Names
Myriophyllum spicatum, also known as Eurasian watermilfoil, is a perennial aquatic plant that is native to Europe, Asia, and North Africa. It is now considered an invasive species in many parts of the world, including North America, where it has been introduced to compete with native aquatic plants.
The plant has several common names, including spiked watermilfoil, Eurasian watermilfoil, and northern watermilfoil. The name "watermilfoil" comes from the plant's feathery, milfoil-like leaves that grow in whorls around the stem.
Appearance and Uses of Myriophyllum spicatum
Myriophyllum spicatum can grow up to 10 feet long and has a single root system that anchors the plant in the mud. The stems of the plant are thin and branched, with feathery leaves that grow in whorls of four around the stem. The leaves are finely divided and range in color from light green to reddish-green.
The plant produces small clusters of flowers that are inconspicuous and greenish in color. The flowers are held above the surface of the water on short stalks. The plant's seeds are small and black, with four to eight spines that aid in their dispersal.
Despite being an invasive species, Myriophyllum spicatum does have some uses. It provides habitat for fish and other aquatic animals, and the plant's dense mats can help reduce erosion along shorelines. Some people also use the plant in aquariums and water gardens, as it can add oxygen to the water and provide a food source for herbivorous fish.
Light Requirements:
Myriophyllum spicatum requires full sun exposure to grow fully, and adequate light is essential for photosynthesis, which allows plants to produce energy. Hence, it is vital to place the plant in a location where it can get at least eight hours of direct sunlight every day.
Temperature Requirements:
The optimum temperature range for the growth and development of Myriophyllum spicatum is between 15-25°C (59-77°F). The plant can survive in temperatures as low as 4°C and as high as 38°C. However, sudden fluctuations in temperature, especially during the winter season, can cause damage to the plant.
Soil Requirements:
Myriophyllum spicatum prefers a nutrient-rich substrate that is slightly alkaline. It can thrive in a wide range of soils, including sandy and clay soils. However, the plant demands an organic-rich substrate that offers high fertility. Additionally, it grows best in soils with pH ranges between 6.5 and 8.2.
Cultivation Methods
Myriophyllum spicatum, commonly known as Eurasian Watermilfoil, is a submerged aquatic plant that grows rapidly in shallow freshwater ponds and lakes. The plant reproduces through stem fragmentation and spreads aggressively, leading to the formation of dense mats that impede water flow and decrease sunlight penetration. Proper cultivation of this plant requires careful management and monitoring.
To cultivate Myriophyllum spicatum, it is best to plant it in a pond or water garden with a depth of at least 2 feet. Plant the stem fragments with roots attached in early spring or fall, and ensure that they are planted in loose, nutrient-rich soil. Myriophyllum spicatum requires moderate to high levels of sunlight, and thus must have access to at least 4-6 hours of direct sunlight every day.
Watering Needs
As a submerged aquatic plant, Myriophyllum spicatum requires an immense amount of water to grow. Ensure that the water in the pond or water garden is always at a sufficient level to keep the plant submerged, as a lack of water will cause the plant to wilt and eventually die off. Additionally, always replace at least 50% of the water in the pond every one to two weeks to prevent the buildup of harmful chemicals and ensure the plant remains healthy.
Fertilization
Fertilization of Myriophyllum spicatum requires special care to avoid over-fertilization, which could lead to the growth of undesirable algae and other aquatic plants. Once planted, regularly add aquatic plant fertilizer at roughly 2-3 week intervals throughout the growth period. This will help ensure that the plant receives the necessary nutrients to fuel its growth and development.
Pruning
Pruning is essential to maintain the healthy growth of Myriophyllum spicatum. Periodic pruning also ensures that the plant remains manageable and does not become too large or dense, leading to stagnant water and poor oxygen flow. It is recommended to prune the plant once every two weeks, removing up to one-third of its length each time. This will prevent overgrowth and ensure the plant remains healthy and vibrant.
Propagation of Myriophyllum spicatum
Myriophyllum spicatum, commonly known as Eurasian watermilfoil or spiked watermilfoil, is a perennial aquatic plant that is native to Europe, Asia, and North Africa. It is now widely distributed throughout the world and is considered a noxious weed in many areas due to its rapid growth and ability to form dense mats that can interfere with recreational activities and native aquatic plant communities. Propagation of Myriophyllum spicatum can be done through two main methods: vegetative propagation and sexual reproduction.
Vegetative Propagation
Vegetative propagation is the most common and efficient method of propagating Myriophyllum spicatum. This involves the fragmentation of the plant and the subsequent growth of new plants from the resulting fragments. The plant can be fragmented naturally by wave action, boat propellers, or waterfowl, and new shoots will grow from the fragments. Vegetative fragmentation can also be induced intentionally by cutting the plant into sections and planting them in new locations. This is typically done in the spring or fall when the plants are actively growing.
Another common method of vegetative propagation involves the use of stem cuttings. This method involves taking cuttings from the stem of a healthy plant and planting them in a rooting medium until roots develop. Once roots have developed, the cuttings can be transplanted into a suitable aquatic environment. This method is typically done in the summer.
Sexual Reproduction
Myriophyllum spicatum can also be propagated through sexual reproduction, although this method is less common. The plant produces small flowers that are pollinated by wind or water. The flowers develop into small seeds that can be dispersed by water or by animals. The seeds can take several months to germinate and require specific conditions, such as cool water temperatures and high levels of light, to grow successfully. Sexual reproduction is typically less effective than vegetative propagation due to the slow growth rate of the seeds and the unpredictability of seed dispersal.
Overall, vegetative propagation is the most effective method of propagating Myriophyllum spicatum, although sexual reproduction can be used in certain circumstances. It is important to note that Myriophyllum spicatum is considered a noxious weed in many areas and should not be propagated or planted without proper authorization and guidance.
Disease Management
Myriophyllum spicatum, also known as Eurasian watermilfoil, can be susceptible to various diseases that may affect its growth and survival. The most common diseases that affect the plant are fungal infections caused by species such as Sclerotinia sclerotiorum and Rhizoctonia solani. These fungi can attack the root, stem, and leaves of the plant, leading to wilting and death. To manage fungal diseases, it is recommended to remove and discard infected plants as soon as possible to prevent the spread of spores to healthy plants. Additionally, keeping the growing area clean and free of debris can help reduce the risk of fungal infections.
Pest Management
Myriophyllum spicatum can also be vulnerable to various pests that can cause significant damage to its leaves and stems. The most common pests that affect the plant include aquatic insects such as weevils, leaf miners, and midges. Weevils can feed on the leaves and stems of the plant, causing extensive damage and reducing its overall growth. Leaf miners can cause similar damage by tunneling through the leaves, while midges can feed on the plant's reproductive structures, affecting its ability to reproduce. To manage pests, it is recommended to use biological control methods such as using beneficial insects or introducing natural predators to the growing area. Additionally, using physical barriers such as nets or screens around the growing area can help prevent pests from reaching the plants.
