How to treat trees for japanese beetles
Controlling Japanese Beetles - Get Rid of Japanese Beetles
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Advice Pests and Diseases Controlling Japanese Beetles
Japanese beetle damage is pretty easy to identify. Usually, the bugs can be caught in the act. The telltale signs of Japanese beetles include skeletonized leaves or total defoliation. Japanese beetles also love to eat rosebuds — from the inside out. Keep in mind that Japanese beetles are seldom found west of the Mississippi River, but chances are good that they're headed your way.
The beetles are strangely beautiful: roughly 3/8" long and 1/4" wide. They have shiny, metallic-green bodies and copper-colored wing covers.
Four Ways to Control Japanese Beetles
A multi-part attack is best. Start by spraying the affected plants with Japanese Beetle Killer (pyrethrin) or neem at the first sign of attack.
Pyrethrin-based insecticide is a safe and effective way to control these pests on vegetables, grapes, raspberries, flowers, roses, trees and shrubs. In addition to controlling Japanese beetles, it also controls cucumber beetles, flea beetles, cabbageworms, Colorado potato beetles, and more.
Neem oil comes from a tree; when sprayed on plants, it reduces feeding. Scientists call it an antifeedant. Important: neem works best when applications begin at first sign of attack.
A Japanese beetle, feasting on tender, new leaves of a rose bush. Photo: David Grist
Japanese beetles are slow. You can easily pick them off plants with your hands and toss them into a bucket of soapy water. Do it in the morning when the beetles are less alert.
Although the following solutions won't provide immediate gratification, you will be better off next year. Beneficial nematodes kill the grubs that turn into Japanese beetles. Ideally, apply them in spring before the beetles emerge. The second half of this 1-2 prevention punch is Milky Spore, which also kills grubs. It takes a year or so to get established in your soil, but it keeps working for 10 years or more.
A Japanese beetle trap is recommended only if you have a large yard, and can place the trap away from your garden. If you have a small yard, you'll just be telling the beetles, "The party's at my house!" If you use a trap, put it out for a day or two at a time every couple of weeks.
Why Neem Oil?
Not only does it control Japanese beetles in the heat of their feeding frenzy, it also controls: adelgids, wooly adelgids, sawflies, aphids, sawfly larvae, cabbage loopers, lacebugs, scale, cabbageworm, leafhoppers, chinch bugs, mealybugs, spider mites, crickets, earwigs, flea beetles, mole crickets, squash bugs, pear slugs, tent caterpillars, grasshoppers, pear psyllas, thrips, green stink bugs, whiteflies, psyllids, gypsy moth caterpillars, rose slugs, harlequin bugs, rust mites and other soft-bodied insects.
Neem can also be used on roses in a formulation called Rose Rx, which prevents diseases that plague roses: blackspot, powdery mildew, rust, scab, anthracnose and more.
Even if you use Milky Spore and beneficial nematodes, you can still get Japanese beetles. Yes, they're slow, but they can fly up to a mile for a good meal. Neem or pyrethrin-based sprays can control these outbreaks.
If you have these plants, monitor them closely:
- Japanese maple
- Norway maple
- Crape myrtle
- Pin oak
- Cherry (plum, apricot, peach)
Japanese Beetle Killer
Neem Oil Concentrate works on a wide variety of pests including Japanese beetles, aphids, mites, whiteflies, flea beetles and earwigs.
Last updated: 01/23/2021
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Controlling Insect Pests in the Garden
Controlling Japanese Beetles and Grubs
How to Help Your Trees & Shrubs Survive a Japanese Beetle Invasion
by Fielding Tree Care / August 24, 2020 / All things trees, apple, ash, elm, Shrub Care, Signs of Tree Damage / Infestation, Tree Fertilization, Tree Maintenance
This spring and summer Denver residents have spent more time than ever tending to their gardens, making additions to their landscaping, and beautifying their homes. Caring for the plants and trees on your property can feel therapeutic and release pent up stress during these difficult times.
As we all strive to stay safe and socially distanced during the COVID-19 pandemic, home has become our refuge. The front porch, outdoor patio, and garden areas provide a welcome retreat for relaxation and escape.
Many Denver locals are going all-out on their gardens this year, but are dismayed to find that an old foe is back in the flower beds. The destructive Japanese Beetle is on the verge of an all-out invasion. Imagine putting in hours and hours of hard work, only to have your gorgeous rose bushes skeletonized before your very eyes!
Japanese Beetles don’t just target flowers, they also deal serious damage to several trees species native to the Denver region such as American Linden, American Elm, and Norway Maple. Learn more about this pest and how to protect your trees and shrubs from impending invasion.Japanese Beetle Basics
First recognized in Denver in 2006, Japanese beetles have grown enormously in population since then, becoming an unwanted part of the Colorado landscape. The county has tried tirelessly to curb these pests, but the Japanese beetle continues to spread and cause more damage each year.
Recognizing The Japanese Beetle
Japanese beetles are easily recognizable by their metallic green shell. The beetles may look pretty, but they are considered one of the most relentlessly destructive urban pests in the US!
- Japanese beetle adult: identifiable by its oval form, which is about 7/16-inch in length. Its Torso is bright, shiny emerald green, and its wings are copper-colored. On the sides of its body are five patches of whitish hairs. On its head and fan-like antennae.
- Japanese beetle larvae: a grub can be identified by its milky white body, dark head, and the legs on the thorax that are well developed. The body often curves into a C-shape. To distinguish Japanese beetle grubs from other varieties, look for a pattern of hairs on the hind end of the abdomen which forms a distinctive V-shape.
Japanese Beetle Life-cycle
According to Colorado State University experts, the Japanese beetle has a one-year life cycle. Adults may begin to emerge from the soil in early June and are usually in full force in early summer – from late June through early August. However, some adults may be found well into September. Japanese beetles remain active until the soil temperature drops below 50 degrees.
Adult beetles actively feed and mate on foliage and flowers of their host plants. Seeking out moist soil, adult beetles lay a small cluster of eggs among the plant roots daily. A total of 40-60 eggs may be laid by each Japanese beetle female during the course of her 4-8 week life span!
Here are some other pertinent facts on the Japanese beetle from the Colorado State University Extension:
- Japanese beetle adults chew flower blossoms and leaves of many commonly grown plants.
- Japanese beetle larvae are a type of white grub that feeds on the roots of grasses.
- Adults are best controlled by handpicking or by use of certain insecticide sprays.
- Japanese beetle traps can capture many adults, but do not reduce damage to nearby plants.
- Japanese beetle larvae can be controlled with certain insecticides or by insect parasitic nematodes.
At-risk Trees, Plants, and Shrubs
There are 300 plant varieties that the beetles crave and prey on, but here are the ones at the top of their list:
- Virginia Creeper
- American Linden
- American Elm
- Norway Maple
- American Mountain-ash
- Crabapple & Appletree
Not sure exactly what varieties of trees are on your property, wondering f they are a risk? Schedule one of our expert arborists to come out for a quick consultation! They are happy to help you identify your tree species and advise on next-steps for proper care.
Japanese Beetle Destruction
What does it look like when a tree or shrub is infested by Japanese beetles? Here are some classic signs:
- Skeleton-like leaves: Japanese beetles devour the tender parts of the leaves, leaving veins. The result is severely damaged, lace-like leaves. They do not fall off, instead the leaves hang on the branch until they dry out.
- Scorched appearance: Trees with a very severe infestation can develop a scorched look to the bark and leaves.
- Beetle activity: Japanese beetles are not sneaky! They can easily be spotted flying from tree to shrub, feasting on leaves. If you have a Japanese beetle infestation, you will see them be especially active on warm sunny days.
A Japanese beetle can wreak havoc on your landscape leaving terrible damage. Luckily there are preventative measures you can take and treatment options for stopping these pests in their tracks.Treatment Options For Japanese Beetles
If you google treatments for Japanese beetles, you’ll come across ads for traps. County officials, however, warn that due to population size and explosive growth of the beetles traps have essentially been rendered useless. Repeated trials have demonstrated that the use of such traps does not reduce the number of beetles damaging nearby vegetation.
Handpicking is another possible option, but is only partially effective when employed in small plantings. Beetles can be easily picked off or you can shake infested plants over a collecting container in the early morning. This strategy is still hit or miss, and yields unreliable results.
Lepitect is an environmentally safe soil injection insecticide. It is a unique solution that provides rapid results, delivering systemic control of many key shade tree pests. It is a highly effective tool for the management of Japanese beetles. One application of Lepitect will give 30 days of efficacy for insect larvae.
Lepitect Comes In Two Forms:
- The soil injected form of Lepitect treats 25 inches of tree diameter (DBH) at a high rate and 50 inches at the low rate.
- The tree injected form of Lepitect treats 71 inches of diameter (DBH).
Soil injection of Lepitect involves placing chemicals in liquid form near the roots in the soil for root uptake. The chemicals are water-soluble, similar to other injection methods. For best results, Lepitect will be applied to soil that is moist, but not soaked.
With soil injection, also called the soil drench method, the insecticide is mixed in water and simply poured on the soil near the tree’s root crown. For this to work mulch or other surface organic matter has to be pulled back. The chemical must be poured directly on the soil. Afterward, the mulch can be replaced.
Soil injection methods vary somewhat, but typical recommendations are to inject chemicals 2–4 inches deep with a high-pressure injector either within 18 inches of the trunk or on a grid. The amount of Lepitect to be applied depends on trunk diameter, and diameters are added if multiple trees are being treated in an area.
Trunk injection is another application option. Injection of Lepitect into a tree trunk directly applies concentrated systemic pesticides into a tree’s vascular tissues for faster translocation. Trunk injection has the same benefits as soil injection, in that the pesticide quickly enters the tree’s vascular system. Both applications of Lepitect are particularly effective in controlling some of the most troublesome insect pests, like Japanese Beetles and Aphids.
Here are details on how Lepitect is typically applied:
- Application Method: Pull back landscape mulch, landscape fabric, and surface organic matter before making soil applications to ensure the solution is delivered to the mineral soil. Measure the diameter of the tree at breast height (DBH), 4’6” above the soil line. For multi-stemmed trees and shrubs, use the cumulative diameter of individual stems at the soil line instead of DBH.
- Application Timing: Make applications to actively growing plants just prior to or when insects first appear. Repeat applications every 2 weeks as needed.
Some pesticides and insecticides can be dangerous to birds, other insects, and nearby plants if they enter water runoff. You can breathe easily and feel confident when you choose Lepitect to manage pests in your lawn. It is safe and environmentally friendly!
Environmentally conscientious advantages of trunk and soil injection Lepitect:
- Little, if any, pesticide applied is wasted to drift or runoff, because it can be applied precisely to where it is needed in the tree.
- Can apply Lepitect with trunk or soil injection during windy and rainy weather because there is no drift or runoff.
- Trunk injections can be used on sites where soil treatments may not be practical, effective, or appropriate, including trees growing on excessively wet, sandy, compacted, or restricted-soil environments.
- There is little non-target organism exposure; therefore, it is safe in environmentally-sensitive areas. Your nearby shrubs and plants will not be affected.
- Injection methods for treating some of Denver’s troublesome pests, such as Japanese beetles and aphids, can be particularly useful.
- During Lepitect soil injection application trees are not wounded.
- The soil injection and trunk injection methods require very few tools and can be completed quickly.
Spending time in your outdoor space is precious during the spring and summer months. Your beautiful trees and shrubs create the serene atmosphere for all your favorite activities. Protect your lawn and landscape from spring pests with environmentally safe Lepitect.
Schedule with one of our friendly certified arborists for a quick and free consultation. We can’t wait to help you eliminate Japanese beetles from your property for good! Contact us at Fielding Tree & Shrub Care for more information on this simple, safe, and effective solution!
how to protect yourself from the Japanese beetle
Popillia japonica - is a beetle that appeared in Italy only a few years ago , but it is spreading more and more massively and uncontrollably, causing serious problems for agriculture and horticulture.
This is an exotic insect, and like the Asian beetle and Drosophila suzukii, this Japanese beetle is capable of causing great damage to many cultivated plant species . Popilia is actually considered one of the quarantine pests, and the most affected regions are actively working to keep it under control.
The production of private gardens and orchards has of course not been spared, so it is important to know the insect and to understand, at least as far as possible, environmentally friendly means by which to intervene to limit its damage.
Characteristics of the Japanese beetle
Popilia japonica - beetle of Japanese origin , also present in the US for some time and absent from Europe until 2014, except in the Azores (Portugal). In the summer of the same year, its first discovery was made in some municipalities of the Ticino Valley. Therefore, its distribution began in northern Italy, starting with Lombardy and Piedmont .
Adults of Popilia have an average length of about 1 centimeter and are metallic green with bronze highlights on the back . What distinguishes it from other similar insects such as the common beetle (Phylloperta horticola) is the presence of 12 tufts of white hairs (5 on each side of the abdomen and 2 wider on the terminal part).
Life cycle in Italy
An insect in northern Italy completes one generation in the year and adults emerge from the ground between late May and early June. We can find it mainly in large groups to feed on plants, and during July it has the peak of its maximum presence of .
Damage and species affected by popillia
The Japanese beetle operates on two types of damage:
- Popillia Japonica larvae move in the soil and feed on plant roots.
- Popillia Japonica adults are polyphagous and this is a problem as many cultivated species can be affected.
Popolya affects open ground crops, ornamental trees and shrubs, fruit plants and vegetables, about 300 species in total, and therefore can cause problems for both the vegetable garden and the garden.
However, the most severe damage occurs to a limited group of species, including peach, cherry, plum, apricot, pit, grapevine and blueberry among fruit trees and green beans among vegetables.
There is no doubt about its recognition, since in these cases it is present in large numbers on the leaves of , which appear to be widely perforated or completely eaten.
How to deal with Popillia japonica
Popillia control is not the prerogative of an individual producer: the regional phytosanitary services of the affected areas carry out coordinated actions, including through special traps.
Briefly what can be done to biologically control the Japanese beetle, and then we will go into the details point by point:
- Presence monitoring and alarm if detected.
- Limit watering if insects are present to prevent damage to larvae in summer.
- Harvesting by hand, even with chickens.
- Use insect screens.
- Use neem oil as an insecticide.
- Enter natural antagonists.
Popillia japonica traps and monitoring
Insect monitoring is a fundamental practice and is carried out by the Phytosanitary Service at the regional level.
In addition to visual checks, special traps with specific attractants are used.
In particular, the Phytosanitary Services of Lombardy and Piedmont use two types of traps :
- Yellow-green jar with special wings suitable for capture.
- Tripod covered with insecticide coated net.
Both types of traps work well and are approved by the Ministries of Health and Agriculture, but should only be used by authorized personnel .
The disadvantage of these tools is that their attraction force exceeds their gripping ability, resulting in them attracting many samples even at a distance of hundreds of meters. As a result, increases the damage to vegetation present in the immediate vicinity of trap . Moreover, these traps assume that all citizens respect them and do not interfere with them.
What to do if Popillia Japonica appears
If we find Popillia, it is important to report it. Here's what to do:
- Make sure it's this beetle (check for tufts of white hair on the sides of the belly)
- Photograph and destroy insects immediately after.
- Pay attention to affected plants.
- Please notify the regional phytosanitary authorities (e.g. for the Lombardy region: [email protected], for the Ticino park: [email protected]).
Beware of irrigation
Eggs and young larvae of Popilia are very susceptible to dehydration, and hot and dry summers inhibit their development.
Therefore, it is recommended to limit watering to the required amount of , avoiding too much soil moisture, which instead promotes egg development.
Help of chickens and manual collection
Those who have chickens or hens can turn to them for help in protecting Popilil: it seems that domestic birds are voracious. In this case, all you need to do is collect all the specimens that are on the plants and take them to the chicken coop.
Regardless of whether there are chickens or hens, manual harvesting has a great positive effect on the localization of this insect.
Even if it requires perseverance and a little time, at least at the level of a kitchen garden or a private garden, it can be practiced with good results.
A really effective way to control this feared pest is the use of insect nets to be placed to cover the rows or individual plants to be treated after fruit set.
This can be a little tricky and cumbersome, but it is a major mechanical hindrance to Popillia, as well as Asian bed bugs and other pests, and is completely sustainable, making it suitable for organic farming.
Biological insecticide treatment
Popilia japonica can be treated with azadirachtin (neem oil) as recommended by the Ticino Park Authority itself for repellency.
Natural pyrethrum products are not fully registered against Popilia, but if you use this product against other harmful insects, you may see results against Popilia at the same time. For non-professional use there is no problem and no license is required, but you should always read the product label carefully and follow all instructions.
Antagonistic organisms for biological protection
The Japanese beetle in Italy has an uncontrolled distribution, since does not find enough antagonists in nature. As an external element of our ecosystem, it does not have particularly effective pathogens or predators. Therefore, in order to counter this with natural methods, it was decided to introduce natural antagonists of this species.
The natural limiters of Popillia are mainly entomopathogenic nematode Heterorabditis bacteriophora and entomopathogenic fungus Metarizhium anisopliae , which have been introduced into the environment since 2016.
Within a few years the effect should be noticeable, and we hope that the damage to Popillia Japonica will be more limited, like other local pests, or at least in our country for some time.
Treatment of trees from bark beetle, how to save a tree from bark beetle
This pest feeds on wood. It is quite difficult to see beetles on young healthy trees. Ephedra, when trying to be colonized by parasites, secrete resin, stone fruit - sticky gum, which clog all cracks, literally drown insects and prevent lesions from developing. But if the “food source” is weakened or the environment around it is favorable for population growth, you will have a long struggle with bark beetles and treatment of plantings.
Insect First Aid
When the sum of positive temperatures from the beginning of the year reaches 140-150 degrees, the first flight of a printer working in spruce forests begins. Then in mid-May comes the turn of fruit sapwood in the gardens.
Each tree has its own bark beetle and, if no measures are taken, after a while they will settle everywhere, begin to multiply and devour the bark, sapwood, branches. With a fairly warm winter in the spring, expect an invasion. It is very difficult to save an infected area. Often, the only remedy for treating a tree from a bark beetle is the Friendship saw.
To prevent this from happening, you need to act before the appearance of insects. To create effective protection, you will need to remove all debris from the site, remove or burn dead wood, old leaves, stumps, cut down diseased trees, and cut dried branches. A mandatory measure is spraying, which is carried out before the flowering of fruit crops.
If you do not have ready-made insecticides on hand, you can use your own preparation from an aqueous solution of liquid soap and carbolic acid (for 5 liters of water, 2 cups of other ingredients). Before use, the solution is diluted with water (1:4).
When planting young vegetation, pest control must be carried out immediately. This can be a simple remedy from a one percent solution of karbofos, which is sprayed on the trunks from top to bottom. If the beetle has already arrived, spray again, making sure that the drug does not fall on the leaves.
Drill dust on a tree at the beginning of the season is a sure sign that insects are already nesting inside the trunk. If this fate befell one or two cultures, try to make an incision on the bark above the hole and move it to the side. There you will find the whole family. Without thinking about how to save the tree from the bark beetle, start manually cleaning the passages with a sharp knife.
Inspect the entire barrel and run the procedure on all burrows found. This is a long and painstaking business, but there is a chance that you will be able to cure the planting. After hunting for a beetle, treat the surface with karbofos or chlorophos and pour it with an immunostimulant (for example, Zircon). The next watering and spraying should be done in 5-7 days and repeat this for a month.
Treat or remove?
To understand how to act, you need to assess the degree of damage. It is possible to cure a tree from a bark beetle only at the initial stage of the disease.
When insects have just settled, it is worth trying to save an apple tree or other fruit crop. If the holes on the trunk were found only at the end of August, do not rush with treatment. The new beetles have already flown out, leaving shattered wood in their wake. And although while the crown is still green, the vegetation most likely cannot be saved, since the structure and sap flow are disturbed. Numerous passages with exfoliating bark are the first sign of death. In this case, only removing the tree and destroying it will help.
Treatment requires a whole range of measures aimed at:
- elimination of mechanical damage - cracks, hollows, cuts;
- pest control - treatment with chemical and biological preparations, installation of repellers;
- strengthening the immunity of vegetation - immunostimulants, top dressing with fertilizers;
- removal of breeding centers of beetles - cutting down and destruction of diseased and weakened plantings;
- tree protection.
Only then will the result be effective.
When an infestation is detected, spraying with insecticides (Kliper, Confidor, Decis, Aktara and others) or biologically active preparations based on nematodes can be used. Moreover, both types of funds are not used simultaneously.
Intra-stem injections have proven themselves, which spread along the entire stem with sap flow and have a paralyzing effect on the central nervous system of insects. They stop eating, moving, reproducing, and eventually die. You can inject the funds directly into the gnawed passages or enter them with special devices under high pressure through the holes made.
After the procedure, the holes are closed with special plugs to protect against the ingress of germs and bacteria. Over time, the cork overgrows with new bark.
The drugs used can be different, both professional (Arbojet, Mauget) and well-known: