Pest of the Month: Spider Mites
This month we are going to be discussing spider mites and the damage they can do to your trees, even in the winter time!
It’s important to always be on guard for pests and diseases throughout the year, which is why we are sharing one pest every month of the year to inform you of what your trees could be facing.
First, let’s talk about what spider mites are.
What are Spider Mites?
Aleksey Gnilenkov from Moscow, Russia
These pests are members of the Acari (mite) family Tetranychidae – this group includes about 1200 different species. You will typically find them under the leaves of plants, where they spin protective silk webs and puncture the cells of the plants to feed.
Spider mites are known for feeding on over several hundred different species of plants.
These bugs are less than .04 of an inch (1mm) in size, and they vary quite a bit in color. They are referred to as “spiders” because many of the species spin silk webbing to protect their group from predators. On top of that, they lay very small, spherical transparent eggs as well.
When they are in optical conditions (about 80 degrees Fahrenheit and dry), they can hatch in about 3 days, and the bugs can sexually mature in about 5 days. The female spider mites are able to lay up to 20 eggs per day, and they typically live for between 2 to 4 weeks, so they can lay hundreds of eggs in their lifetime.
Because they are reproduced and mature at some a quick rate, spider mites are able to adapt quickly to completely resist pesticides, making them even more difficult to get rid of than your average tree pest.
Identifying Spider Mites
Not sure if you have spider mites on your trees or not?
Plants and trees that are infested with the red spider mites will begin to look sickly and have a dusty appearance on the underside of the leaves. If you take a closer look at the “dust,” you will notice that it is moving and is actually the mites. You may also notice some silk webbing on the underside of the leaves and branches as well.
You won’t be able to easily make out the details of the red spider mites without a magnifying glass, with your naked eye they will look like small specks of red dust. The other types of spider mites may have some red, but they will have other colors mixed in as well.
How Do They Cause Damage To Your Trees?
Aleksey Gnilenkov from Moscow, Russia
So what damage can these pests cause?
Spider mites cause major damage by sucking out the cell contents from the leaves of the plants and trees they live on. Having just a small amount of the mites won’t be too big of an issue, but huge populations (enough that you notice masses on the plants), can damage them, especially the herbaceous ones.
The damage will initially show up as a smattering of lightly colored dots on the leaves, sometimes making the whole leaf a bronze color. As they continue to feed on the leaves, they turn yellow or red and then drop off of the plants and trees. Also, large amounts of the webbing will cover the twigs, fruit, and leaves typically, and the damage is often worse when compounded by water stress.
A significant amount of leaf loss won’t cause a lack of fruit on fruit trees during the year they are being infested, however they could seriously impact the crop of the next year.
For vegetable crops, this loss of leaves may have a significant impact on their yield and can lead to sunburning too. Plants that grow things like beans and sugar peas can be directly damaged, and the pests can cause a lot of aesthetic concern for ornamentals .
How To Prevent Spider Mites
Tony Wills from Wikipedia Commons
Spider mites are most active in colder weather, so typically you will see infestations in the late fall and early spring.
To control and stop these bugs from spreading, the best options are by using their natural predators in the wild. These include ladybugs, lacewings, and other predatory mites. You can typically get any of these other bugs from reputable garden supply centers and websites .
Pesticides can also be used to eliminate these pests too. Insecticidal oils and soaps typically work best, although be careful with using them as they can kill their natural predators as well.Preventing them from happening at all is of course the best solution. To do this, keep your plants healthy and thriving and make sure they are free of any dirt or debris. Also make sure that your plants and trees get plenty of water, as the red spider mites prefer an extremely dry environment.
Our Final Thoughts on Spider Mites
We hope you found our guide to dealing with red spider mites to be helpful. Simply make sure that your trees and plants are well taken care of, and that the proper procedures are taken when the pests do take over.
If you do need additional help with the pests on your trees, feel free to contact Arborist Now for any assistance you need!