One of the most important things to note is the fact that white grubs do not refer to a single class. Rather, it is a collective term that refers to the larval stage of different kinds of insects. Although there are different species, most of them share the same characteristics as a larva. The color is usually dirty white or gray. They have a brown head and the length usually has an average of 3/8 to 2 inches. When they are resting, they form a C shape. June beetle bugs, on the other hand, crawls on its back. Most of them also have six strong legs, except in the case of June beetle bugs.
White Grub’s Habitat
White grubs are common in places where it is sunny. They dwell on the soil, which is why they commonly affect turfgrass. They feed on the roots of their host plant, which is where the damage starts.
Identifying White Grub’s Damage
Among others, turfgrass is perhaps the most common host for white grubs, along with Napier grass. It also feeds on the roots of various shrubs and ornamental plants. Other common hosts include potato, carrot, strawberry, clover, alfalfa, asparagus, pineapples, and tobacco. When they transform into adults, on the other hand, they thrive in coniferous and deciduous trees.
Below are some of the most common signs indicative of the presence of white grubs:
- If you notice an unusual increase in the number of birds in the garden, this is one of the most common indications that white grubs are present. Skunks, racoons, and moles will also dig the ground. These can also act as excellent predators, which will help to keep the population of the larvae in check.
- There will also be discoloration in the areas where white grubs feed, especially in the case of turfgrass. There will be brown or yellow patches, which will be indicative of how the host plant is no longer able to obtain the nutrients that it needs for survival.
- Aside from discoloration, the lawn will also appear dry and parch. You might think that watering will restore its peak condition. But if the damage is severe, regardless of how hard you try, you can no longer save it
- Wilting is also a common symptom that you need to watch out for, especially for tall grass. In some cases, you will also notice the turf turn spongy when you walk on the top of it.
Results of Infestation
The destruction of grass roots is one of the most common results of massive infestation from white grubs. Dead spots will start to appear, showing brown and dry patches. It starts with aesthetic damage, but eventually, the host will die. This is a big problem not only in garden lawns, but even on golf courses and other fields that are covered with grass.
How to Get Rid of White Grubs
Natural and Organic Solutions
The following are some of the best ways to eliminate white grubs in a manner that is safe and effective:
- The first thing that you have to do is to take advantage of physical control measures. Among others, handpicking is one of the solutions that might work, especially if the area that you will treat is just a small portion. This is an exhausting task if you have a large lawn. It is best to pick them manually early in the morning, a time when they are not very active. Knock them down in a bucket of soapy water, which will kill them. Do this at least every day until there is a noticeable decline in their population or damages.
- Plowing is another solution that can yield a high level of effectiveness, especially if you do it the end of spring or start of autumn. This will not only destroy the eggs and larvae, but will also expose them to natural predators.
- When it comes to biological control, on the other hand, their natural enemies will also extend a helping hand. You can consider growing plants that will attract birds. In turn, these birds will feed on the larvae. You will also benefit from using entomopathogenic nematodes. They are roundworms that serve as a parasite for a wide array of insects. Ants, ground beetles, and parasitic wasps can also deliver an excellent job when it comes to controlling the population of white grubs.
- There are also commercial products that are available. Pay attention to the products that you will use and make sure that there are no active ingredients that are toxic. Rather than those containing harsh chemicals, you can opt for products that use the right ingredients. For instance, azadirachtin is an excellent choice. It comes from neem seeds and is one of the best ways to kill insects naturally.
Application of chemicals will yield a higher level of success through the proper timing of application. Early summer is best, which is a time wherein they are small and active. However, take note that their growth is sporadic, which makes spraying chemicals quite challenging.
Among others, trichlorfon and carbaryl are some of the most common options. Professional application is best, especially because they contain toxic ingredients. The use of chemicals, however, should be the last item in your list of elimination measures. This is because they will harm not only the larvae you are targeting, but even the beneficial insects.
How to Prevent White Grubs
Spraying of insecticides is not only a curative approach, but also a preventive measure. Do it before the appearance of the white grubs, making sure that you will kill them before they wreak havoc. To add, another great way to prevent their presence is to keep your lawn in its peak condition. The adoption of cultural practices to manage the lawn will help to keep it free from infestation. During the summer, it will also be good to mow the lawn at a height of at least 7.5 centimeters, which will help to discover where the eggs are and remove them before they hatch. It is also important to prevent watering too often. Too much moisture will make the soil more attractive for laying eggs.