Methods 1: Part 1: Identification of Tetranychus urticae.
1, check the leaf surface. If plants are really invaded by spider mites, yellow spots will appear on the leaves. When the sun shines on the leaves, you may see silver or bronze and silver stripes on the leaves. Although spider mites usually attack the bottom of leaves, they sometimes greedily eat the top of leaves and flowers. In the end, the spider mite will suck through a hole in the leaf, which is the most obvious evidence of spider mite infestation.
Even if there are no holes in the leaves, your plants may still be invaded by spider mites, so you need to pay attention to other signs of invasion.
Other signs of damage caused by Tetranychus urticae include deformation, distortion, withering, leaf spots, stripes or leaf discoloration. If the spider mite is seriously damaged, the leaves may start to fall off.
2, check whether the plant is white mesh. These are some signs of tetranychus urticae infection. These nets usually surround the parts of plants that get food. Please note that not all spider mites make webs.
3. Confirm the existence of Tetranychus urticae. Tetranychus urticae is so small that it is hard to see with the naked eye. However, you can take a piece of white paper and put it under the plants you suspect to be disturbed, and then gently shake the stem of one of the leaves to confirm their existence. A certain number of spider mites will fall on the paper. You can easily see them through a magnifying glass.
Tetranychus urticae has different colors, including red, green, yellow and brown. They have eight legs and usually move very slowly.
Pay attention to whether there are spots on the back of Tetranychus urticae. This spot is called Tetranychus urticae, which is very difficult to remove.
You must pay special attention to certain plant species. Tetranychus mites seem to prefer to invade certain plants. Pay special attention to whether there are mites in miniature roses, fruit trees, bananas, potted begonia, beans, mint, broad-leaved weeds, strawberries, jasmine flowers and indoor potted plants.
Please note that Tetranychus urticae is known to attack more than 100 different plants.
5. In a dry and dusty climate, we should pay special attention to the infestation of spider mites. Tetranychus urticae is the most harmful in this climate, because they are thirsty and need to find water from plant leaves urgently. This also means that they will be attracted to any plants that grow under the glass, including those placed on the windowsill.
Method 2: Part II: Natural method to remove Tetranychus urticae.
1, clean and wipe indoor potted plants regularly. This method is convenient for residents to clean indoor plants, and it is also the most effective and non-toxic method to remove Tetranychus urticae. You can wash plants with clean water or warm water mixed with very mild dishwashing liquid or soap. You can use any kind of soap, but olive soap is particularly effective.
Immerse the sponge in water, and then wipe the individual leaves of the plant; Or pour water into the spray bottle and spray the bottom of the leaf.
If the invasion continues, the above soap solution can be used again after six days. Note that some kinds of plants are particularly sensitive to soap, so you can test the soap solution on a small part of the plant to make sure there is no problem, and then spray the whole plant.
2. Spray outdoor plants with water pipes. Install the sprinkler on the outdoor water pipe, and then water the plants attacked by spider mites outdoors. Set the water potential to high pressure and aim at the bottom of the leaves as much as possible. This should help to wash off spider mites.
3. Alcohol for external use. External use of isopropanol and alcohol can effectively kill Tetranychus urticae. Just pour a little alcohol on a clean cloth and then wipe the bottom of the disturbed plant leaves.
4. Use plant acaricide. There are several acaricides in the market that use natural ingredients to kill Tetranychus urticae without harming plants and other insects. The three most popular plant acaricides are as follows: Pyrethrum is a natural insecticide extracted from compositae plants. If you want to deal with Tetranychus urticae, pyrethrum will be the first choice. However, some species of Tetranychus urticae are resistant to pyrethrum, so we should pay attention to the plant condition after spraying pyrethrum.
Cinnamaldehyde is a harmless insecticide, which comes from cinnamon oil. Although it can be safely and effectively used to kill tetranychus urticae, it cannot destroy the eggs of tetranychus urticae. Therefore, it must be reused every three days for two weeks to ensure that all newly hatched larvae are destroyed.
Neem oil is an acaricide extracted from neem fruit. It is suitable for eliminating the damage of Tetranychus urticae, and can also be used as acaricide and treating powdery mildew.
5. Remove the severely damaged plant parts immediately. Pick up the fallen leaves on the plants and pull out the badly damaged leaves. This will prevent tetranychus mites from affecting other nearby plants. Put the leaves in a plastic bag and seal them, then throw them into the garbage or burn them. If the whole plant is infected, you should consider removing it completely. This gives other plants a better chance of survival.
Water the affected plants only from top to bottom. Once the plant parts invaded by spider mites are found, they need to be removed immediately.
6. Control weeds around plants. Don't let Yuzryha mites have other hiding places and attack the plants you really want to grow in the garden through weeds. In particular, it is necessary to remove all broad-leaved weeds.
After harvesting, all remaining debris, including stumps, fallen leaves and other plant materials, should be removed.
7. Use homemade herbal tea. If you want to make your own acaricide at home, you can put one tablespoon of cinnamon powder, one tablespoon of clove powder and two tablespoons of Italian spice powder into about 946 ml of water to make herbal tea. Boil the water and turn off the fire. Once the water cools slightly, add two tablespoons of chopped fresh garlic. Let the water stand until it is completely cooled, and then filter out the residue with cloth or coffee filter paper.
Add a little detergent to the tea and pour it into the spray bottle. Spray tea every three days on the bottom of leaves invaded by spider mites for two weeks. This will effectively kill Tetranychus urticae.
8. Use essential oils and organic salts. Rosemary essential oil is a particularly effective organic insecticide. You can mix rosemary essential oil with water and spray it on the leaves of plants damaged by spider mites. Fortunately, rosemary oil will kill Tetranychus urticae, but at the same time keep beneficial predatory mites.
Fatty acids or potassium salts have abrasive effects on mites. Potassium salt can be used in the afternoon to keep the plants moist to the maximum extent, thus successfully eliminating Tetranychus urticae.
Spraying water on susceptible plants at night makes the environment colder and wetter. This can effectively eliminate Tetranychus urticae, because they prefer warm and dry environment.
9. Encourage ladybugs and other insects that prey on spider mites to haunt your garden. If predatory insects (such as Chrysopa larvae, predatory thrips and ladybugs) can survive in the garden, it will help you to eliminate most of the spider mites. First of all, one of the main reasons for the growth of Tetranychus urticae in your garden is that pesticides have eliminated their natural enemies. Therefore, you should avoid using pesticides, such as carbaryl, malathion and imidacloprid. You can buy these insects through advertisements in the Internet, gardening centers or gardening magazines. In addition, herbs such as amaranth and Lithospermum can naturally attract ladybugs to the garden.
You can ask the supplier for details about how to make full use of carnivorous insects. It should be noted that the success rate of these insects in mixed areas is low.
Predatory mites can also be used to control tetranychus urticae. You can look for Chilean phytophagous mites or other predatory mites in the horticultural center (please consult the retailer for the trade name of insects, which varies from country to country), and then follow the release instructions of insects.
Under proper conditions, predatory mites can kill Tetranychus urticae. Interestingly, ladybugs can let predatory mites go, but only for tetranychus urticae.
Method 3: Part 3: Chemical removal of Tetranychus urticae.
1. Spray insecticide soap indoors. Tetranychus urticae can be prevented by using water to remove tetranychus urticae and spraying insecticidal soap.
2. Buy patented products suitable for removing outdoor Tetranychus urticae. You can buy this spray or wet towel in gardening centers and hardware stores. Use the product according to the manufacturer's instructions. Dormant oil can be used in early spring and horticultural light oil can be used in summer.
If you choose to spray some chemicals (such as mirex, dichlorvos, triazole tin, phenylbutazone, bromopropyl ester, chemicals that inhibit the growth and reproduction of Tetranychus urticae, etc.). ), it is not recommended that you use the same product more than three times in the growing season of plants. This can reduce the chances of tetranychus urticae producing antibodies to chemicals.
3. Try to remove Tetranychus urticae with sulfur. Sulfur powder or wettable sulfur can be used. But don't use sulfur in hot climate and follow the manufacturer's instructions.
Tips Some tetranychus mites can be seen with the naked eye, while others are very small. If there are only a few tetranychus mites, it is difficult to be seen with the naked eye, but when many tetranychus mites gather together, you can see them at close range. If you want to watch Tetranychus urticae at close range, you can use a magnifying glass.
Tetranychus urticae may or may not be red. Horticulturists usually classify tetranychus mites in the same category regardless of their colors, because the damage they cause is very similar.
Tetranychus urticae can be divided into different families. They are closely related to octopoda, and can spin silk around their feeding parts, which is convenient for activities and self-defense. Tetranychidae may be the most threatening mite to plants. They can pierce a single plant cell, suck liquid from stem cells and fill plant cells with air. Tetranychus urticae is the most common tetranychus urticae, which mainly harms gardens, greenhouses and houses.
Warning: Eliminating Tetranychus urticae is very challenging. You need to persevere and try not to create an environment that tetranychus mites like (most tetranychus mites like warm, sheltered and some water, and some prefer very dry environment).
It should be noted that the use of pesticides may also eliminate carnivorous insects. These insects can control the infestation of spider mites and restore the natural balance. Therefore, please use pesticides or insecticides with caution.
Biological control of Tetranychus urticae is better than pesticide control. This is because Tetranychus urticae can quickly produce antibodies to pesticides.
Tetranychus urticae will spread some plant viruses, so you must try to eliminate them one by one.