Controlling Japanes Beetle

Figure 1.

Japanese Beetle emergence has not quite begun here in Northern Illinois, but beetles have been spotted in other locations of the Midwest.  Once Japanese Beetle have emerged in one location, it is only a matter of time before it emerges in another.  They tend to gravitate to Honeycrisp trees first (Figure 1).  Due to the large amount of carbohydrates produced by the Honeycrisp trees, which is what makes the variety so sweet, the Japanese Beetle is seemingly attracted to it just like we are!  Honeycrisp seem to be the first leaves that attract them and then they move on to raspberries and several other berry and apple varieties.   

Monitoring for Japanese Beetle

Adult Japanese beetles emerge from the soil and live from 30 to 45 days feeding on plants over a four-to-six-week period.  The adults produce aggregation pheromones that attract individuals (both males and females) to the same feeding location. Adults can fly up to five miles to locate a feeding site; however, they tend to fly only short distances to feed and lay eggs.   The adult beetles normally emerge during the last week of June through July. The first beetles out of the ground seek out that suitable food , like Honeycrisp, and begin to feed. These early arrivals then begin to release that aggregation pheromone (odor) that attracts additional adults. Newly emerged females also release a sex pheromone that attracts males. After feeding and mating for a day or two, the females burrow into the soil to lay eggs at a depth of 2 to 4 inches. Females lay 1 to 5 eggs before returning to plants to feed and mate. This cycle of feeding, mating and egg laying continues until the female has laid 40 to 60 eggs. Most of the eggs are laid by mid-August though adults may be found until the first frost. The eggs hatch in 8 to 14 days and the first instar larvae dig to the soil surface to feed on roots and organic material. The first instars shed their skin (molt) in 17 to 25 days. The second instars take 18 to 45 days to mature and molt again. Most of the grubs are in the third instar by late September and by October they dig deeper into the soil to overwinter. The grubs return to thesurface in the spring as the soil temperature warms, usually in mid-April. The grubs continue their development and form a pupa in an earthen cell 1 to 3 inches in the soil. 

Figure 2.

When you see those first few beetles, that is the time to begin your plan of attack.  Those first few beetles are the food source scouts that will emit the aggregation pheromone letting other beetles know that a feast is on! The Japanese beetle adults feed through the upper leaf surface (epidermis) and leaf center (mesophyll), leaving the lower epidermis intact. Adults usually avoid feeding on tissue between leaf veins, resulting in leaves appearing lace-like or skeletonized (Figure 2). Controlling those first few beetles can give you a head start on stopping the feeding/mating cycle.

 Control for Japanese Beetle

There are some control options for the adult life stage One is physical removal and/or trapping of adults:  Removing beetles by hand, or trapping, may provide adequate protection  for  small plantings  when  beetle  numbers are low.  However, Japanese  beetle  adults  are capable  of  migrating  from  other  areas,  and  the presence  of  beetles  on  or  near  a  plant  will  attract more   beetles.  Consequently,   use   of   Japanese beetle traps often attracts more beetles, and results in subsequent damage to plants.  

Figure 3.

The other alternative is chemical control of adults:  Several insecticides are labeled  for  use  against  adult  Japanese  beetles.  Always  follow  label  directions.    Typically, this may entail 2 treatments during the peak beetle flight. Homeowners should make their first application before damage becomes intolerable and beetles are still abundant. The need for repeated applications can be curtailed by inspecting plants for additional beetle damage prior to applying a second treatment. Neem products containing Azadirachtin can be effective repellents that can reduce defoliation when applied regularly (but no more than weekly) during beetle flight.  Apply before defoliation becomes intolerable. In years when beetle populations are very high, noticeable defoliation may occur because adults will consume a small amount of insecticide tainted leaves before they are killed.  Treat  foliage  and flowers thoroughly.  For optimal control, apply in the late afternoon when beetles are most active.

 

Several other insecticides can be used for Japanese beetle control including those used for codling moth and apple maggot control like acetamaprid.  There are others like Sevin, but I do not recommend the use of Sevin since it is toxic to bees and to beneficial insects and can act like a fruit thinner on your fruit, causing you to lose your fruit in excessive heat.   Acetamiprid is a soft, conventional control and is available as  Ortho Flower, Fruit & Vegetable Insect Killer (Figure 3).  This is a ready to use product that contains .006% acetamiprid, a synthetic organic compound of the family of chemicals that acts as neonicotinoid insecticides. Acetamiprid is a contact insecticide for sucking-type insects and can be applied as a foliar spray or a soil treatment.  When sprayed in the evening at sunset, it will not harm bees or other beneficial insects. 

 

I have been informed by Ortho that their Flower, Fruit and Vegetable Spray has been discontinued, although there may be several retailers that have inventory on hand.  They have replaced this product with two new products,
Ortho® Tree & Shrub Fruit Tree Spray Concentrate which is Pyrethrin and Neem Oil and
Ortho® Insect Killer Tree & Shrub Concentrate which is Spinosad.  The Pyrethrin/Neem Oil product will work well on Japanese Beetle, but the Spinosad product is not as effective.

If you do choose to use chemical controls make sure that the plant you are applying to is listed on the label as well as Japanese Beetles. If controlling Japanese Beetles on food crops such brambles or apples – make sure to follow the harvest-restriction date on the label. Always READ and FOLLOW the label and do not apply at rates higher than listed.

 

For further reading on Japanese Beetle, refer to this article by Rufus Isaacs and John Wise from Michigan Sate University:  Managing Japanese Beetles in Fruit Crops.  ________________________________________

This publication contains pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registration, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these  recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned.  The author assumes no liability resulting from the use of these recommendations.

Time to Plan For Plum Curculio

Plum Curculio Ovipositing Egg

With apple scab season in our midst, and petal fall coming to an end, it is time to turn our attention to several insect pests. Plum curculio (PC) is one of the most difficult insect pests to contain.  They enter the orchard from the perimeter after the adults pass the winter hidden under leaves, along fence rows, in brush piles, rock walls and in other protected places. In spring when the weather warms up (mean temperature 60°F. or maximum temperature above 75°F.), about the same time apples are blooming, the adults become active. The adult plum curculio beetles, pictured to the left, emerge right around or just after petal fall, to feed on apple buds, flowers, leaves and young fruit.  The duration of full bloom to petal fall is usually about 5 to 10 days.  From petal fall to fruit set is generally another 5 to 10 days, depending on temperatures.  Once the fruit sets, female beetles cut holes in the young fruit and deposit one egg in each cavity. 

 

 

These sites, called oviposition stings, are easily identified by their crescent shaped cuts. Unlike codling moth, the larvae of plum curculio rarely cause damage to the fruit. The fruit is primarily damaged superficially by the egg-laying and feeding by the adults. These "stings" will cork over and cause an indentation in the fruit as it matures making it look deformed and unsightly.

The question then becomes, how do we control them??  Pesticide application at this time is very important for plum curculio control. To prevent fruit drop, and due to toxicity to bees if there are still blooms on the trees, do not use carbaryl (Sevin®) or any pyrethrin based spray as these are highly toxic to honey bees and other pollinators as well as any beneficial insects. Any other pesticides should be applied int he evening when the honey bees have returned tot heor hives.  For home growers, an acetamiprid spray such as Ortho® Flower, Fruit & Vegetable Insect Killer Ready-Spray is a deterrent.  If no blooms are present  on any trees, a pyrethrin based spray can be used as a deterrent, even though there may be no fruit.  Picking up and disposing of any fallen fruit will reduce problems with plum curculio, other insects, and many plant diseases. For conventional growers, Avaunt or Assail are two choices you might use, based on your codling moth protocol and your apple maggot protocol.

For a pure organic spray, the two most frequently used insecticides are Surround® and Pyganic®, both certified organic. The organic products may need to be sprayed multiple times for complete control at 7 to 10 day intervals or after any rain. And, as always, follow all label directions on any spray product. 

For a complete Fact Sheet on Plum Curculio, consult the Cornell University Plum Curculio Fact Sheet and for an in depth look at this pest.
__________________________________________

This publication contains pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registration, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these  recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned.  The author assumes no liability resulting from the use of these recommendations.

Apple Scab Season Has Arrived

Based on our NEWA (Network for Environment and Weather Applications) Apple Scab Model, we have had multiple scab infection events beginning March 23 with spore maturity being very low (see chart below). But, with the first infection period, even though leaf tissues had not formed yet, the scab season has officially begun!  With no leaf tissue showing prior to green tip, any previous infection period would have no immediate effect on the leaf tissue, but we now know that there are spores out there.  Since we had our copper spray put on right at green tip the evening of April 7 and 8, we were protected from the infection once the spores began to mature.  With spore maturity and discharge being very low, the risk is also very low, but we still need to be protected because any high temperature day can cause the spores to mature very quickly. 

 

 

Ascospores mature as spring progresses with a few ascospores usually maturing by bud break (green tip). The proportion of ascospores maturing progresses slowly until about the tight cluster stage of blossom development. From tight cluster through bloom the percentage of mature ascospores rapidly increases with most ascospores matured by the end of bloom.  In the chart below, we cab see that the ascospore maturity level is still quite low.

 

Unusual weather conditions may contribute to significant ascospore discharges earlier than or later than the model predicts, and for that reason, we want to be sure we have a protective cover spray on the trees.. 

Mature ascospores begin to discharge into the air within 30 minutes during periods of rain. When rainfall begins at night, discharge may be delayed until daybreak. Ascospore discharge usually peaks from pink through bloom, and nearly all ascospores have been discharged within 1 or 2 weeks after petal fall.

Copper has been shown to be a protectant against scab on the tissue that has been covered, but not on any new tissue that would have grown since that copper spray was put on.   If no copper spray has been put on your trees as of today, and you have not put any other protectant on like Captan or Mancozeb, you still have time to get an eradicant fungicide put on your trees in the form of Immunox, which has a 72 to 96 hour reach back ability.  That means that you have up to 72 to 96 hours to get a spray on which will still be effective against any scab infection event 72 to 96 hours previous. Immunox is a xylum mobile fungicide which means when applied to leaves it will move throughout the leaves it was deposited on but will not move out of that leaf (McGrath, M.T. 2004. What are Fungicides. The Plant Health Instructor. DOI: 10.1094/PHI-I-2004-0825-01. Updated 2016.) 

For the home grower who may not have a weather station or scab model to help predict the apple scab infection periods, monitoring for apple scab can be quite complicated.  But there is an alternative.  Unless wetness periods are being monitored as outlined in the section above, you can simply apply protective or eradicant fungicides at regular intervals beginning with green tip. Spraying should be done every 7 to 10 days, depending on the number of rain events between sprays.  If there are no rain events between sprays, a single protectant spray will last at least 10 days but not more than 14 days, based on the product's label directions.  You will need to make sure that your trees and fruit are protected prior to any rain event if you are going to use only a protectant.  A good protectant is Captan or Mancozeb.  But, a protectant can lose its effectivness after 2" of rain, so you also want to keep an eradicant on hand like a myclobutanil, which is available as Spectracide Immunox, which I mention above.  

 

A protectant like Captan has to be applied prior to a rain event.  If no protection is available during the wetting event, then only an eradicant like Immunox can be applied that has a reach back of 72 to 96 hours as I have stated above.  That means that it can still have an effect on the scab pathogen for up to 96 hours after a wetting event, although it is a good practice to use the shorter 72 hours.. A good option is to actually use both a protectant and an erdicant at the same time, like Captan mixed with Immunox, which will give you both protection and eradicant action after a wetting event. Be sure to monitor wetness periods throughout the spring to insure that trees are always adequately protected. 

 But, regardless of the type of mobility that a fungicide possesses, no fungicide is effective after the development of visible disease symptoms. For that reason, timely fungicide application before establishment of the disease is important for optimal disease management.

_____________________________________________________________

 
This publication contains pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registration, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these  recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned.  The author assumes no liability resulting from the use of these recommendations.

 

It's July and Japanese Beetle is Beginning to Emerge

Figure 1.

Japanese Beetle emergence has begun here in Northern Illinois, but seems to be very spotty.  But once it has emerged in one location, it is only a matter of time before it emerges in another.  I noticed the first beetle last Monday and today they were still not in full on our Honeycrisp trees (Figure 1).  Due to the large amount of carbohydrates produced by the Honeycrisp trees, which is what makes the variety so sweet, the Japanese Beetle is seemingly attracted to it just like we are!  Honeycrisp seem to be the first leaves that attract them and then they move on to raspberries and several other berry varieties.   

Monitoring for Japanese Beetle

Adult Japanese beetles emerge from the soil and live from 30 to 45 days feeding on plants over a four-to-six-week period.  The adults produce aggregation pheromones that attract individuals (both males and females) to the same feeding location. Adults can fly up to five miles to locate a feeding site; however, they tend to fly only short distances to feed and lay eggs.   The adult beetles normally emerge during the last week of June through July. The first beetles out of the ground seek out that suitable food , like Honeycrisp, and begin to feed. These early arrivals then begin to release that aggregation pheromone (odor) that attracts additional adults. Newly emerged females also release a sex pheromone that attracts males. After feeding and mating for a day or two, the females burrow into the soil to lay eggs at a depth of 2 to 4 inches. Females lay 1 to 5 eggs before returning to plants to feed and mate. This cycle of feeding, mating and egg laying continues until the female has laid 40 to 60 eggs. Most of the eggs are laid by mid-August though adults may be found until the first frost. The eggs hatch in 8 to 14 days and the first instar larvae dig to the soil surface to feed on roots and organic material. The first instars shed their skin (molt) in 17 to 25 days. The second instars take 18 to 45 days to mature and molt again. Most of the grubs are in the third instar by late September and by October they dig deeper into the soil to overwinter. The grubs return to thesurface in the spring as the soil temperature warms, usually in mid-April. The grubs continue their development and form a pupa in an earthen cell 1 to 3 inches in the soil. 

Figure 2.

When you see those first few beetles, that is the time to begin you plan of attack.  Those first few beetles are the food source scouts that will emit the aggregation pheromone letting other beetles know that a feast is on! The Japanese beetle adults feed through the upper leaf surface (epidermis) and leaf center (mesophyll), leaving the lower epidermis intact. Adults usually avoid feeding on tissue between leaf veins, resulting in leaves appearing lace-like or skeletonized (Figure 2). Controlling those first few beetles can give you a head start on stopping the feeding/mating cycle.

 Control for Japanese Beetle

There are some control options for the adult life stage One is physical removal and/or trapping of adults:  Removing beetles by hand, or trapping, may provide adequate protection  for  small plantings  when  beetle  numbers are low.  However, Japanese  beetle  adults  are capable  of  migrating  from  other  areas,  and  the presence  of  beetles  on  or  near  a  plant  will  attract more   beetles.  Consequently,   use   of   Japanese beetle traps often attracts more beetles, and results in subsequent damage to plants.  

Figure 3.

The other alternative is chemical control of adults:  Several insecticides are labeled  for  use  against  adult  Japanese  beetles.  Always  follow  label  directions.    Typically, this may entail 2 treatments during the peak beetle flight. Homeowners should make their first application before damage becomes intolerable and beetles are still abundant. The need for repeated applications can be curtailed by inspecting plants for additional beetle damage prior to applying a second treatment. Neem products containing Azadirachtin can be effective repellents that can reduce defoliation when applied regularly (but no more than weekly) during beetle flight.  Apply before defoliation becomes intolerable. In years when beetle populations are very high, noticeable defoliation may occur because adults will consume a small amount of insecticide tainted leaves before they are killed.  Treat  foliage  and flowers thoroughly.  For optimal control, apply in the late afternoon when beetles are most active. Several other insecticides can be used for Japanese beetle control including those used for codling moth and apple maggot control like acetamaprid.  There are others like Sevin, but I do not recommend the use of Sevin since it is toxic to bees and to beneficial insects.   Acetamiprid is a soft, conventional control and is available as  Ortho Flower, Fruit & Vegetable Insect Killer (Figure 3).  This is a ready to use product that contains .006% acetamiprid, a synthetic organic compound of the family of chemicals that acts as neonicotinoid insecticides. Acetamiprid is a contact insecticide for sucking-type insects and can be applied as a foliar spray or a soil treatment.  When sprayed in the evening at sunset, it will not harm bees or other beneficial insects. 

If you do choose to use chemical controls make sure that the plant you are applying to is listed on the label as well as Japanese Beetles. If controlling Japanese Beetles on food crops such brambles or apples – make sure to follow the harvest-restriction date on the label. Always READ and FOLLOW the label and do not apply at rates higher than listed.

This publication contains pesticide recommendations that are subject to change at any time. These recommendations are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. Due to constantly changing labels and product registration, some of the recommendations given in this writing may no longer be legal by the time you read them. If any information in these  recommendations disagrees with the label, the recommendation must be disregarded. No endorsement is intended for products mentioned, nor is criticism meant for products not mentioned.  The author assumes no liability resulting from the use of these recommendations.

Codling Moth Flight Begins......Very Slowly!

Everyone likes to eat apples, including over 70 insects, and a long list of fungi and bacteria.  To produce good tasting, good looking fruit, we have to control those pests.  We have discussed plum curculio in the May 29 post, but of all the flying pests we encounter in the upper Midwest, codling moth (CM) is one of  the insect pests needing to be controlled the most.  Codling moth is responsible for the proverbial worm in the apple, so to speak! Yet, so far this spring, we have only trapped 2 CM (codling moth) in traps thus far.  With the cooler nights, flight has been remarkably low.  So, before CM flights becomes consistent, let's review the development and movement of CM.

Codling moth (CM) is a small moth whose caterpillars bore into the fruits of apple and pear trees during mid- to late-spring and summer.  Codling moth is the cause of what is often referred to as "the proverbial worm in the apple". The caterpillars of this insect can damage a high proportion of the fruits on apple trees in gardens in a small amount of time. 

Codling Moth Larvae

Newly-hatched larvae (caterpillars) chew through the fruit skin and bore their way to the core. The presence in fruit of one or more holes plugged with frass (excrement) is characteristic of attack by codling moth. The larvae enter the fruit through the sides, stem end, or calyx end, and a syrupy substance may exude from the holes as the fruit matures. Shallow entries called "stings" result when larvae penetrate a short distance and then die from insecticide poisoning or natural causes.

The eggs, larvae and pupae of codling moth each have specific physiological time requirements to complete development before they transform to the next stage. Temperature also affects the flight, mating, and egg laying activities of the adults. Although the minimum threshold for emergence of moths is 50 degrees Fahrenheit, male moths do not fly until temperatures exceed 55.4 degrees F and codling moths do not mate until temperatures exceed 60.8 degrees F in the evening beginning at or right after sunset.

   

Pheromone lure with trapped moths.

To determine when flight begins for codling moth, commercial growers make use of pheromone traps.  Once moths have been trapped for  two consecutive days in a row, a biofix is set  that initiates the beginning of growing-degree-day calculations.  We know that at 100 degree days after the biofix date codling moths begin to lay eggs and those eggs begin to hatch at 250 degree days after biofix.  It is this information that aids in the timing of necessary sprays for codling moth so they do not damage fruit.  Growers wishing to time sprays based on egg development and hatch should make an application of an insecticide at 250 DD (base 50 degrees F) after the first sustained capture of males in the sex pheromone traps.  Here is a Detailed Growing Degree Day Model for Codling Moth.   

 

We have not yet established a biofix for CM this spring and may establish one within the next few days  But for the home orchardist who does not have the benefit of a weather station or other means to calculate degree days, a simple tree growth stage time table can be followed.  Codling moths usually start flying at bloom time or just after bloom time at petal fall and approximately at the same time as plum curculio.  Eggs laid by these moths begin to hatch about two weeks after petal fall, depending on the weather. You can apply the first codling moth spray at this time, about two weeks after petal fall, to prevent larvae from entering the fruit. Because most insecticide residues last 7 to 10 days and moths are continuously present throughout the summer, apply a spray every 7 to 10 days to prevent later broods of codling moth larvae from entering apple and pear fruits. If using a natural product like Spinosad, then spray after every rain due to washoff.  Always follow the label directions of any spray you may use.

Several insecticides can be used for codling moth control including acetmaprid and/or spinosad.  Acetamiprid is a soft, conventional control and is available as  Ortho Flower, Fruit & Vegetable Insect Killer.  This is a ready to use product that contains .006% acetamiprid, and is also available in a concentrate containing .5% acetamiprid, a synthetic organic compound of the family of chemicals that acts as neonicotinoid insecticides. Acetamiprid is a contact, translaminar insecticide for sucking-type insects and can be applied as a foliar spray. Translaminar insecticides are absorbed by leaves and can move through the leaf to the opposite surface they contact. They are not truly systemic and do not move throughout the entire plant. Acetamiprid acts on a broad spectrum of insects, including aphids, thrips, plum curculio, apple maggot and Lepidoptera, especially codling moth.  When sprayed in the evening at sunset, it will not harm bees or other beneficial insects. Be sure to follow all label directions on the bottle for proper application.

An all natural approach is available in the form of Bonide’s Captain Jack’s Dead Bug Brew.  Captain Jack's Deadbug Brew® contains Spinosad (spin-OH-sid), a product first isolated from a naturally occurring soil dwelling bacterium that was collected on a Caribbean island from an abandoned rum distillery. Deadbug Brew® kills bagworms, borers, beetles, caterpillars, codling moth, gypsy moth, loopers, leaf miners, spider mites, tent caterpillars, thrips and more! Use on fruits, vegetables, berries, citrus, grapes, nuts and ornamentals and approved for organic gardening.

For additional information, see the following fact sheets which are available from local university extension services:

https://ecommons.cornell.edu/bitstream/handle/1813/43086/codling-moth-FS-NYSIPM.pdf

http://extension.psu.edu/plants/tree-fruit/insects-mites/factsheets/codling-moth

 Reference in this publication to any specific commercial product, process, or service, or the use

of any trade, firm, or corporation name is for general informational purposes only and does not

constitute an endorsement or certification of any kind by Royal Oak Farm.

People using spray products assume responsibility for their use

in accordance with current label directions of the manufacturer.

Our First Major Insect of the Growing Season

Plum Curculio Ovipositing Egg

With apple scab season in our midst, and petal fall ending, it is time to turn our attention to several insect pests.  I have had the first sighting of plum curculio activity in the orchard today.   Plum curculio (PC) is one of the most difficult insect pests to contain.  They enter the orchard from the perimeter after the adults pass the winter hidden under leaves, along fence rows, in brush piles, rock walls and in other protected places. In spring when the weather warms up (mean temperature 60°F. or maximum temperature above 75°F.), about the same time apples are blooming, the adults become active. The adult plum curculio beetles, pictured to the left, emerge right around or just after petal fall, to feed on apple buds, flowers, leaves and young fruit.  The duration of full bloom to petal fall is usually about 5 to 10 days.  From petal fall to fruit set is generally another 5 to 10 days, depending on temperatures.  Once the fruit sets, female beetles cut holes in the young fruit and deposit one egg in each cavity. 

 

 

These sites, called oviposition stings, are easily identified by their crescent shaped cuts. Unlike codling moth, the larvae of plum curculio rarely cause damage to the fruit. The fruit is primarily damaged superficially by the egg-laying and feeding by the adults. These "stings" will cork over and cause an indentation in the fruit as it matures making it look deformed and unsightly.

The question then becomes, how do we control them??  Pesticide application at this time is very important for plum curculio control. To prevent fruit drop, and due to toxicity to bees if there are still blooms on the trees, do not use carbaryl (Sevin®) or any pyrethrin based spray as these are highly toxic to honey bees and other pollinators as well as any beneficial insects. For home growers, an acetamiprid spray such as Ortho® Flower, Fruit & Vegetable Insect Killer Ready-Spray is a deterrent.  If no blooms are present  on any trees, a pyrethrin based spray can be used as a deterrent, even though there may be no fruit.  Picking up and disposing of any fallen fruit will reduce problems with plum curculio, other insects, and many plant diseases. For conventional growers, Avaunt or Assail are two choices you might use, based on your codling moth protocol and your apple maggot protocol.

For a pure organic spray, the two most frequently used insecticides are Surround® and Pyganic®, both certified organic. The organic products may need to be sprayed multiple times for complete control at 7 to 10 day intervals or after any rain. And, as always, follow all label directions on any spray product. 

For a complete Fact Sheet on Plum Curculio, consult the Cornell University Plum Curculio Fact Sheet and for an in depth look at 

 Reference in this publication to any specific commercial product, process, or service, or the use

of any trade, firm, or corporation name is for general informational purposes only and does not

constitute an endorsement or certification of any kind by Royal Oak Farm.

People using spray products assume responsibility for their use

in accordance with current label directions of the manufacturer.

Time to Start Monitoring for Apple Maggot

Fig. 1

Last season we trapped the first apple maggot fly on June 30. at about 1150 Degree Days from March 1.  We are at 985 DD as of today at 6:38 PM, so it is time to get out the  apple maggot traps  and get them set.  It only takes one trapped fly to  determine that they have arrived to the orchard!  The apple maggot (AM) is native to the Midwestern US and is considered a primary pest, along with plum curculio (PC), and codling moth (CM), which have been covered in previous posts. The adult apple maggot fly resembles a small housefly in size, with a black body, eyes of dark red, with the thorax and abdomen having distinctive white or cream colored bands. The AM is distinguished from other similar, and closely related flies, like cherry fruit fly and black cherry fruit fly, by the variation in dark banding on its wings (See Fig. 1).  

Fig. 2

The AM overwinters in the pupal stage in soil. As soil temperatures rise in early spring, development of pupae commences.  The adult fly first emergence begins shortly thereafter (early summer, mid to late June in upper Illinois). A feeding and mating period (pre-oviposition) of approximately 7-10 days is followed by egg laying directly under the skin of the apple. Females may deposit eggs over an approximate 30 day period laying as many as 300-500 eggs.

Fig. 3

Egg-laying punctures cause dimples and distortion in the outer flesh of fruits. These punctures appear as pinpricks on the fruit surface. Larvae tunnel throughout the fruit leaving irregular trails.(Fig. 2) As eggs hatch, larvae funnel through fruit flesh leaving a winding brown trail.(Fig. 3)  Egg laying usually ceases in early to late August; however, it may continue longer if drought conditions exist throughout August.

Monitoring For Apple Maggot

Fig. 4

When monitoring for AM, the apple maggot fly tends to show a preference for golden delicious varieties, but no variety is immune from attack.  Sticky red spheres are effective monitoring devices for adult AM flies (Fig. 4). Females are attracted to the sphere for mating and egg laying activities and are trapped by the sticky coating. Hang traps shortly before expected adult emergence (mid to late June in upper Illinois). First emergence may be detected by checking traps daily until the first fly is spotted on the trap.

Hang the sphere in the proximity to fruit at eye level on the perimeter of the south or southeast side of the tree. Attach the ball in a sturdy stem about 1 foot above a fruit cluster of approximately 6-10, cleaning out the foliage and other fruit for at least 18 inches to sides and top of the trap so it is easily visible. The spheres attract the insects that come within a few yards of them; therefore, capture of ONE AM on any one trap at a time would indicate the need for an immediate control application. Once the pesticide is applied, AM captures are disregarded for the period during which the protective spray is effective (varies according to pesticide used).

Control for Apple Maggot

Fig 5.

Several insecticides can be used for apple maggot control including those used for codling moth control like acetmaprid and/or spinosad.  Acetamiprid is a soft, conventional control and is available as  Ortho Flower, Fruit & Vegetable Insect Killer (Fig. 5).  This is a ready to use product that contains .006% acetamiprid, a synthetic organic compound of the family of chemicals that acts as neonicotinoid insecticides. Acetamiprid is a contact insecticide for sucking-type insects and can be applied as a foliar spray or a soil treatment. Acetamiprid acts on a broad spectrum of insects, including aphids, thrips, plum curculio, apple maggot and Lepidoptera, especially codling moth.  When sprayed in the evening at sunset, it will not harm bees or other beneficial insects.  Be sure to follow all label directions on the bottle for proper application.

Fig. 6

An all natural approach is available in the form of Bonide’s Captain Jack’s Dead Bug Brew (Fig. 6).  Captain Jack's Deadbug Brew® contains Spinosad (spin-OH-sid), a product first isolated from a naturally occurring soil dwelling bacterium that was collected on a Caribbean island from an abandoned rum distillery. Deadbug Brew® kills bagworms, borers, beetles, caterpillars, codling moth, gypsy moth, loopers, leaf miners, spider mites, tent caterpillars, thrips and more! Use on fruits, vegetables, berries, citrus, grapes, nuts and ornamentals and approved for organic gardening.

As always, be sure to follow all label directions on the bottle for proper application.

For additional information, see the following fact sheets and guides  which are available from local university extension services:

https://ecommons.cornell.edu/bitstream/handle/1813/43071/apple-maggot-FS-NYSIPM.pdf?sequence=1&isAllowed=y

http://extension.psu.edu/plants/tree-fruit/insects-mites/factsheets/apple-maggot

https://www.extension.purdue.edu/extmedia/ID/ID-146-W.pdf

Reference in this blog to any specific commercial product, process, or service, or the use of any trade, firm, or corporation name is for general informational purposes only and does not constitute an endorsement, recommendation, or certification of any kind by Royal Oak Farm, Inc.   People using such products assume responsibility for their use in accordance with current label directions of the manufacturer.
 

Rainy Weather Means Apple Scab and More Apple Scab

This 2018 growing season thus far is proving to be one of the more severe apple scab seasons.  As of today, June 19, we have had eight apple scab infection periods and have had several of those infection periods last for more than 36 hours and two of them lasting more than 48 hours. That has made it nearly impossible to control primary scab outbreaks.  With that being the case, we are at a point of now having to protect fruit from secondary scab.

Fig. 1

Season-long control is difficult if primary infections develop, like those in Fig. 1, which produce secondary inoculum placing fruit at risk for secondary, conidial infections.   With primary ascospores possibly depleted, we will have to continue to monitor scab infection events and maintain spray coverage accordingly for at least two more weeks, if not longer, since we have found primary lesions, like those in Fig. 2 on McIntosh and McIntosh hybrids like Cortland and Empire.  If you have seen lesions like those in Fig. 2, on your trees, then you will need to protect your fruit from secondary lesions.

Fig. 2

The best product for protecting your fruit is Captan, a protectant, so that means that your trees will need to be sprayed with Captan at the full labelled rate prior to any rain event to protect your fruit.  If there are no rain events between sprays, a single protectant spray will last at least 10 days but not more than 14 days, based on the product's labeled directions.  You will need to make sure that your trees and fruit are protected prior to any rain event if when using only a protectant. But, a protectant can lose its effectivness after 2" of rain, so you also want to keep an eradicant on hand like myclobutanil, which is available as Spectracide Immunox. A protectant like Captan has to be applied prior to a rain event.  If no protection is available during the wetting event, then only an eradicant like Immunox can be applied that has a reach back of at least 48 hours.  That means that it can still have an effect on the scab pathogen for up to 48 hours after a wetting event. A good option is to actually use both a protectant and an erdicant at the same time, like Captan mixed with Immunox, which will give you both protection and eradicant action after a wetting event. 

As always, be sure to follow the label directions on any spray product you may use.   For further information on control of apple scab, refer to:

 http://royaloakfarmorchard.blogspot.com/2018/04/apple-scab-season-approaches.html