What You Need to Know About Chara
Pond owners are familiar with Chara. This can be the most difficult species of pond algae that you could ever encounter. If you have a pond and you have a Chara population explosion, you have to know the algae species well. You have to do your homework, so that you can eliminate the aggressive Chara. As a pond owner, who spent a significant amount of time and thought in establishing a pond, you need to make sure that your investment is not ruined. Take the time to understand Chara and learn how you can defeat it.
Chara is also known as muskgrass, sand grass, or stonewort. You’ll know if it’s Chara, you’re dealing with, if it has a garlic odor. You might mistake it as a higher plant because it has seeds and flowers. It is classified as macro-alga because it is multi-cellular. Even so, it does not have true leaves. It has branches and smaller branchlets, which occur in the form of whorls. Spine-shaped cells surround the column-shapes cells of the Chara branchlets and branches. The spines make these algae rough to the touch. Chara usually inhabits the bottoms of lakes, ditches, ponds, and slow-moving rivers. Chara loves calcium-rich or hard water.
Specific Details About Chara
If you have hard water, look forward to having Chara in your pond. This is advanced species of algae resembles larger or higher plants. It can grow up to several feet in length. It is usually gray-green or light green, with forked leaves and branches. It is submerged in the water, densely covering very large areas on the pond’s or lake’s bottom.
The mineral deposits ofnthe surface of Chara leaves make its texture bristly and gritty. Oftentimes, it is mistaken as milfoil or coontail. Because it inhabits the bottom of the pond, it helps stabilize the sediments. Chara is also a source of good cover for pond fish and food for the waterfowl. Chara is also able to support the small, aquatic animals and insects, which then feed the resident aquatic life and visiting birds.
Chara is able to attach itself to your pond’s sandy or muddy bottom. They can also do this to lake and pool bottoms. Only a few species of these algae can survive in saltwater environments. Its body has a branched axis that has district internodes and nodes. It grows false leaves that look like whorled branches. The lower nodes of its axis have multicellular rhizoids that do not have color. This is the part, which attaches to the substratum.
Reproduction of the Chara Species of Algae
Each individual Chara has a node, which has the essential information for reproduction. The nodes have apical cells, while the internodes have elongate cells. The walls of these cells have carbon carbonate deposits and cellulose. Both apical and elongated cells have dense cytoplasm, where chloroplasts are found. They also have a DNA-rich nucleus.
Chara reproduce by vegetatively and sexually.
Vegetative Chara Reproduction
When Chara reproduce vegetatively, it happens through the following:
- Formation of protonema—Chara nodes sometimes have branches that are like protonema, which also have the ability to form new Chara.
- The amylum stars—Some lower Chara nodes are star-shaped. They are called amylum and they have amylum starch. Amylum stars can produce new Chara, thought their developmental process is not known yet.
- The bulbils—Chara’s lower nodes or rhizoids may also form bulbils, which bring forth new plants when they detach from the main plant.
Sexual Chara Reproduction
The Chara’s male reproductive organ is called the antheridium or the globule. Its female reproductive organ is called the oogonium or the nucule. The nucule is usually found above the Chara’s globule, if it is monoecious—though some Chara species are dioecious, wherein reproductive organs are found in separate plant bodies.
The globule develops in the axis of the Chara’s branches that have limited growth. This reproductive cell transforms into a spherical cell and cuts off 1 or 2 discoid cells at the basal part. By the time the antheridium or globule is mature enough, its shields break down. Its antherozooids are freed by the antheridial walls’ gelatimisation or through the formed pore in every antheridial cell.
The oogonium has a short stalk. It is attached to the dwarf shot or the primary lateral leaf of limited growth, which is located above the globule. Upon its maturity, the oogonium contains an elliptical or oval egg, which has five tube-shaped cells. Each cell has at least two spiral turns. Each tubular cell has its upper end cut off, forming a corona or the crown of oogonium. The oogonium is established in the axil of the branches that have limited growth. It comes from a superficial ad axial cell. When this reproductive cell becomes mature, the tube cells separate to form five slits to allow the entrance of the antherozooids.
Fertilization and Germination
Once the slits are formed, the antherozooids enter the tube cells. The oogonium is then fertilized, leading to the formation of the zygote or oospore. The zygote forms a layer of membrane around it and rests inside the oogonium. It falls to the pond’s bottom and germinates after weeks of incubation.
Preventing Chara from Taking Over
Below are some of the ways to prevent Chara infestation in your pond:
- Protect your pond from the nitrogen and phosphorus given out by your septic system, crop fields, barnyards, golf courses, and lawns.
- Decrease the amount of fertilizer, applied around your pond.
- Maintain your septic system well.
- Install vegetative buffer strips around your private pond.
- Built gutters or drains around your pond, so that runoff can be redirected away from it.
You can control Chara by raking, pulling, and cutting the algae itself. Take note that this method is short-lived because the fragments and spores left will produce new Chara. That is why biological and chemical control methods are implemented alongside the physical control process.
Here are some biological ways to control Chara:
- Introduce grass carp into your pond. Access permits for the purchase of this fish.
- Make use of enzyme- or bacteria-based products to eliminate the excess nutrients in your pond water effectively. Without nutrients, Chara won’t be able to proliferate that much. Take note of the requirements, such products have. Also, set aside a budget for them because they can be pricey.
- Install shades over your pond to limit the amount of sunlight, needed by the Chara to produce its own food.
- Establish aeration in the form of waterfalls and fountains. This will add more oxygen to your pond, enabling the helpful bacteria to breakdown the excess nutrients in the water.
If you decide to use chemical control methods against Chara, here are some tips to take note of:
- Chemical treatments are needed several times a year.
- Make sure you properly identify what species of algae is infesting your pond, before you start the chemical doses.
- Compute the right amount of herbicide that you need.
- Obtain a permit before you start using a herbicide.
- Take note that commercial herbicides can cost from 100 USD to at least 1000 USD per acre of pond.
- See to it that you follow the label of the herbicide you purchased. Instructions are carefully noted there, concerning its handling and application.
Chemical or herbicide treatments should be administered before the Chara fully covers your pond. A sunny and calm day is the best time to treat your pond of Chara.