Scouting Notes

Wayne County IPM Notes from July 11-15

Agronomic Crops

Our area alfalfa has shown very low activity from potato leaf hoppers. Remember, that the threshold for potato leaf hoppers is determined by the height of the alfalfa. So, for 12” alfalfa, you would need to average 12 potato leaf hoppers per 10 sweeps to be over threshold. Currently, we are averaging between 1-3 potato leaf hoppers per 10 sweeps. The heat dome over the center of the country has limited our number of southern storms, with many systems moving through our area coming out of the northwest.

The path of most of our recent weather systems.

Insect pests are currently the main concern in corn and soy. Soybeans are being impacted by Japanese beetles and young grasshoppers. Corn is seeing some feeding damage from the corn flea beetle and Japanese beetles. In non-Bt corn, we are finding damage from common armyworms and European corn borer. Essentially all of Wayne County remains in a moisture deficit, even after a decent shot of rain on Wednesday.

Vegetable Crops

Probably the biggest development in our area was the presence of cucurbit downy mildew on a path of cucumbers in southern Wayne County. This means there are active infections in Wayne and Medina counties, and likely the surrounding counties. Ideal conditions for continued progression and infection will exist in the coming days. It is important to take steps now to protect your cucumber and cantaloupe plants.

Powdery mildew found on a cucurbit plant in a Wayne County field.

Powdery mildew on cucurbits continued to spread rapidly, spurned on by several foggy mornings in the area.

As early plantings of summer squash and other cucurbits are harvested, it is important to practice good sanitation in the fields. Do not allow these areas to become diseased and insect infested, as they will only lead to problems in other areas on your farm. Once you are done harvesting an area, it is best to terminate the crop and either incorporate or remove the residue. 2

Other disease concerns revolved around bacterial diseases on peppers and tomatoes. We started to find some bacterial spot/speck on these crops.

Insect wise, it was an active week. Cole crops are still facing significant pressure from flea beetles and imported cabbage worm. European corn borer was identified in a few pepper plantings. Cucurbit crops have increased activity from cucumber beetles, squash bug and squash vine borer.

Small Fruit and Orchards

A few diseases like scab and blister spot have started to show up on leaves in apples orchards, otherwise, disease pressure has subsided after some recent fire blight outbreaks. Insect pressure in apples has slowed some as codling presence has remained low, however, some orchards are still facing some persistent feeding from European red mites.

Some of our oriental fruit moth traps showed a significant flight, with some traps averaging nearly 30 moths per trap. Red mites were still active in the peach blocks as well this week.

The season is wrapping up for some of our raspberry growers, and blueberries won’t be far behind. With blackberries now coming into season, it is still important to be aware of the presence of the spotted wing drosophila, which are still being found in most of our traps. Japanese beetles may also be causing some troubles for small fruit grower, especially those with grape vines. We observed significant defoliation from Japanese beetles on grapes in several areas of the county this week.

Wayne County IPM notes from the week of July 4 – July 8

Agronomic Crops

Some much needed rain made its way through our area this week. Unfortunately, the extended forecast shows a return to a dry pattern. Nonetheless, we are thankful for the moisture that gave some relief for drought stressed crops. Insect pressure has become the leading concern in corn and soy. Japanese beetles are out in force and feeding, in some cases heavily. Other insect pressure can be found via feeding from European corn borer larvae, young grasshoppers, and other various foliar feeding pests. Disease pressure at this point is relatively light at this time.

Vegetable Crops

The warm temperatures and accumulated heat units have kept our insect pests active and building in population. Cucumber beetles, squash bugs and squash vine borer were all active this week in squash plantings and fields. Additionally in squash, we noted our first sighting of powdery mildew in an area of first planting summer squash.

The warm and sunny days have also led to some challenges with sun scald. Unfortunately, the heavy winds and rains from the storms had pushed plants over, which allowed for the first set of vegetables, such as peppers or tomatoes, to be exposed to full sun and extreme heat.

Growers with cole crops may still be battling flea beetle and imported cabbage worms. Significant egg laying from the cabbage white butterflies gives us the heads up to scout our cucurbit crops very closely to watch for hatching eggs and early instar larvae.

Generally, the Japanese beetles have begun their entrance into a wide range of vegetable crops. In some cases, isolated feeding damage may severely damage the foliage and stunt young plants. Frequent scouting can help you make timely management decisions, therefore avoiding significant damage from the Japanese beetles.

Small Fruit and Orchards

European red mites were found in apples and peaches this week, and in a few cases, the populations had reached significant levels, with severe feeding damage present on the foliage. As was the case in vegetable crops, the Japanese beetles feeding on orchard trees and small fruit plants started to cause some significant defoliation.

Spotted wing drosophila were found in all of our traps. Accordingly, small fruit growers should be aware that we are now fully into SWD season.

Fire blight in apples has been our main disease concern to this point. We did note a few cases of apple scab on leaves in some orchards around the area.

Overall, fruit development in orchards and small fruit production areas is coming along nicely and should be greatly benefited by the timely rains.

Wayne County IPM Notes Week of June 20-24, 2022

Agronomic Crops

Last week we discussed in our agronomic crop report about moisture stress in crops from too much rain. This week, we have certainly flipped the script as we are dealing with a flash drought. In a recent Crop Observation and Recommendation Network (C.O.R.N.) article by Taylor Dill and Jamie Hampton, it was shared that we can actually calculate at what point we may see damage from the heat and drought stress in our crops. When temperatures exceed 86 degrees, you can calculate those periods as stress degree days. Once corn reaches 140 stress degree days, the chance of reaching above average yields begins to decrease. Dill and Hampton also point out that “Leaf rolling is a common symptom of high-temperature stress. Yield diminishes by 1% for every 12 hours of leaf rolling during vegetative growth but increases to 1% every four (4) hours during silking. When water is deficient during a heat wave the loss of yield increases after four consecutive days of 93°F or above, not including the stress from leaf rolling. So, the impact of heat stress can be two-fold.”

Japanese beetles in field corn, F. Becker, 2022.

Soybeans are in a similar situation, as shared in the article by Dill and Hampton. “Soybeans have a similar range in temperature to corn for heat stress. Temperatures above 85°F for several consecutive days can cause heat stress. This heat can accelerate maturity because soybeans are photoperiod and temperature-controlled when it comes to flowering. During vegetative stages, these high temperatures can slow or stop photosynthesis because the plant is making an effort to conserve water. Thus, inhibiting new vegetative growth, which is vital for late-planted soybeans. Temperatures above 86°F can also reduce nodulation and therefore N-fixation in the soybean which could have an effect until the reproductive stages.”

Japanese beetles were found in agronomic crops this week. Potato leaf hoppers are present in alfalfa; however, our scouting did not find any significant populations.

Vegetable Crops

Now is a critical time to be monitoring your cucurbit crops for cucumber beetles. Early populations may not seem as evident due to the presence of insecticide in treated seed, however, as the efficacy of the seed treatment diminishes, the cucumber beetle feeding will begin to increase. The threshold for beetles while the plants are in the 2-4 leaf stage is 1 beetle per plant. Once the plant is above the 4-leaf stage, the threshold increases to 3 beetles per plant. The greatest chance for impactful feeding damage and bacterial wilt infection via the cucumber beetle occurs during early season feeding.

Squash bug found in Wayne County on yellow squash. Cucumber beetles feeding in the background. F. Becker, 2022.

Also, of note in cucurbits, the excess moisture and warm conditions allowed for development of some phytophthora cases. If you suspect that you have plants infected by this pathogen, avoid spreading it in your fields by removing and destroying infected fruit and plant material. An integrated approach to managing this disease includes practices such as avoiding excess water, sufficient crop rotations and fungicide treated seed. Additional findings in cucurbits included squash bugs being found this week in an early planting of yellow squash.

An area of yellow squash plants lost due to phytophthora, F. Becker, 2022.

Continue to monitor onions for thrips populations. The recent heavy rain may have prevented populations from building, however, hot dry weather, combined with the increased size and number of leaves can provide the opportunity for thrips numbers to escalate rapidly.

In tomatoes our scouts noted some observations of early blight and Septoria.

Remember to check your crops for any signs of foliar diseases, especially with the amount of soil splashing that took place in the last few weeks. Bacterial and fungal diseases can be spread on the lower leaves of plants when heavy rains splash soil and pathogens onto the foliage. Overall, stress from high temperatures has been evident in a majority of the crops that we are scouting.

Small Fruit and Orchards

Male SWD, Thomas Becker photo, 2022

Female SWD, Thomas Becker photo, 2022.

Spotted winged drosophila have been caught in traps around Wayne County. As we move out of strawberry season into raspberries/blackberries/blueberries, the SWD populations will begin to increase leading to possible infestations in ripening brambles and blueberries.

In apples, we continued to find strikes of fire blight. Conditions have been ideal for fire blight development, although dryer conditions may hinder further development. This week we continued to find aphids in apple trees. Our IPM program identified populations of green apple aphids in several orchards as well as a case of wooly apple aphids. Both aphid species can cause significant damage at this time of year. Accordingly, diligent scouting is a crucial aspect to not allowing either of these aphid species from getting out of hand. The heavy rains likely knocked back some of these aphid populations, but it will be important to monitor aphid populations as dry conditions take hold.

We have had sustained catches (over threshold) of both Codling Moth and Oriental Fruit Moth in apple and peach orchards, respectively. Over the last week, both Codling Moth and Oriental Fruit Moth populations have been trending downward, however, numbers have still exceeded the thresholds.

Now is the time to be managing early season diseases in apples. Scab, rust and powdery mildew are the three main diseases of concern at this point in the season.

Once strawberry harvest is over, it is a good time to consider renovation of the patch. the goals in renovation are to reduce plant numbers by narrowing the rows, remove old foliage (reduces diseases), control weeds, and reduce insect pests. After renovation, regular irrigation and weed control are essential. High yields next year depend on having large, healthy, vigorous plants when fruit buds are initiated in late summer

Grapes are currently around the buckshot berry stage. It is still possible to spray for and manage black rot during this time. We have started catching grape berry moth in our traps.

Wayne County IPM Notes From the Week of June 13-17, 2022

Agronomic Crops

We certainly got our fair share of rain the in last few weeks, but we have also seen a significant increase in temperature just in the last week. Given the warmer weather, slugs may feed on young corn and soybean plants at night and early in the morning but will likely retreat to the soil or under crop residue during the day. The black cutworm was still active in corn, although as some of the corn fields we are scouting are approaching V7, the feeding has not been as severe as compared to some fields that are VE through V3. Black cutworms are much less likely to cut plants at the V4 stage and beyond. Many of the soybean fields in the area are beginning to emerge. We are typically seeing plant maturity anywhere from sprouts to VC (unrolled unifoliolate leaves). We are beginning to find some potato leaf hoppers in the alfalfa. Remember that the best way to scout and check for leaf hopper populations is to use a sweep net. The threshold for potato leaf hoppers is based on the alfalfa height in inches and the number of leaf hoppers per 10 sweeps. If you have more leafhoppers in 10 sweeps than the height of the alfalfa, then you are over threshold.

 

Vegetable Crops

The Colorado Potato Beetle larvae have hatched and are now feeding in both potato and eggplant. When approaching plants to look for them, be cautious. When the beetle is startled, they drop to the ground and may be difficult to see. They do significant damage to the foliage and can cause significant reduction in yield. The Colorado Potato Beetle also has a history of developing resistance to insecticides being used as control measures. This has limited our choices for treatment options. The best way to prevent further resistance is to avoid using the same insecticide repeatedly. At the current plant stage for potato, the threshold is approximately 1 beetle per plant. For eggplant, it is 25 beetles per 50 plants.

In summer squash/zucchini, we are seeing an increase in the number of cucumber beetles. The seed treatment on these plants is beginning to wear off. For fall vine crops that have just been planted in the last few weeks, that seed treatment should still have a few weeks of efficacy left.

In onions, we have noticed an increase in the number of thrips, in many cases approaching an action threshold. Threshold is 25-30 thrips per plant. This week we also found more incidences of slippery skin which was confirmed by the vegetable pathology lab at OARDC earlier this month. Slippery skin is caused by Pseudomonas gladioli. This bacterium is spread via soil splashing from heavy rains and enters the plant through natural openings or openings from mechanical injury. Given the heavy rains we have experienced in the past week, it would probably be a good idea to get out and check your onions.

Overall, tomatoes are continuing to grow rapidly in the greater Wayne County area, with some plantings of field tomatoes beginning to set blooms. We did have a case of timber rot identified in the West Salem area in field tomato. It is important to practice good crop rotations and rotate out of a crop family completely for at least 3-4 years. A complete crop rotation will help to break up disease and pest cycles. Similar to onions, tomatoes can contract bacterial diseases from soil splashing. If you have tomatoes, it may be worthwhile checking the lower canopy of your plants to monitor the presence of any diseases.

Our IPM pest scouts have continued to find Mexican bean leaf beetles in the green beans this week. Light foliar feeding was observed.

With the warmer weather and plants maturing rapidly, the slug threat has greatly reduced in the last week. Any new transplants should still be monitored for feeding, however there should be less of a slug presence for the rest of the growing season.

 

Small Fruit and Orchards

This week we continued to find aphids in apple trees. Our IPM program identified populations of green apple aphids in several orchards as well as a case of wooly apple aphids. Both aphid species can cause significant damage at this time of year. Accordingly, diligent scouting is a crucial aspect to not allowing either of these aphid species from getting out of hand. The heavy rains likely knocked back some of these aphid populations, but it will be important to monitor aphid populations as the weather dries out a bit.

In apples, we continued to so find a few instances of fire blight. Conditions have been ideal for fire blight development, so it is not much of a surprise to see some cases.

We have had sustained catches (over threshold) of both Codling Moth and Oriental Fruit Moth in apple and peach orchards, respectively. Over the last week, both Codling Moth and Oriental Fruit Moth populations have been trending downward, however, numbers have still exceeded the action thresholds.

With the storms over the course of the last week, it is not unlikely that we will see some yield loss from wind, heavy rains, or hail damage in many of the area’s fruit trees.

Now is the time to be managing early season diseases in apples. Scab, rust and powdery mildew are the three main diseases of concern at this point in the season.

Strawberry leaf diseases may appear unsightly right now, however, now is not the time to be managing these leaf diseases. Once harvest is done and during patch renovation it is recommended that you address these concerns, either with a fungicide or with resistant plant varieties. This is also a critical time to be watching for fruit rots such as Botrytis.

Grapes are currently around the buckshot berry stage. It is still possible to spray for and manage black rot during this time.

Wayne County IPM Notes from the Week of August 9 – 13

Agronomic Crops

There was a significant reduction in potato leaf hopper counts this week. This drop is likely due to timely cutting in the fields we scout, along with frequent heavy rains. When wetter weather, or with days that have heavier morning dews occur, potato leafhoppers can diminish quickly due to the entomopathogenic fungi that can cause the population to collapse. When these conditions occur, and populations of potato leafhoppers drop, there is no need to treat.

Field corn is pushing R3-R4, as the silk is now drying down all the way to the kernel and the kernel is filling out and the ears start into maturity. In soybean, pods are developing all of the way up the plant, and pods are starting to fill. As pod fill begins to occur, it is a critical time to be watching for insects like stink bugs that would be damaging the pods and developing seeds.

Vegetable Crops

Squash vine borer damaged plants.

This week brought about many sightings of squash vine borer larva. The adult squash vine borer moths were actively flying and lay eggs about a month ago. We are now seeing plants that are declining in health and when inspected further, are oozing frass and have stems that look shredded. When we split the stem of these plants, in nearly every instance, we found at least one, if not several squash vine borer larvae. Unfortunately, there is nothing that can be done to reverse such severe damage.

A large squash vine borer found feeding in a pumpkin plant.

Flea beetles are feeding on young cabbage and broccoli, and the cabbage worm butterflies are finding their way into these plantings as well. We are starting to see some damage in peppers from the European corn borer and expect the ECB and CEW numbers in the traps to increase in the next week or so.

Small Fruit and Orchards

As apples and peaches are harvested, do not let your guard down on the late season generations of codling moth and oriental fruit moth. This past week was another week of rising codling moth numbers, and consistent oriental fruit moth catches, although the oriental fruit moth numbers have not gone back over threshold.

Grapes damaged by grape berry moth larvae.

Grapes are starting to ripen, and as the season progresses, we are still finding consistent trap catches of grape berry moth. Although it may be too late for some varieties, you may still be able to protect later maturing varieties with a treatment for grape berry moth.

Wayne County IPM Notes from the Week of August 2 – August 6

Agronomic Crops

All of the corn that we are scouting is now at least R1. It is important to keep an eye out for pests like Japanese beetles or northern corn rootworm beetles that can cause damage to the crop by feeding on and clipping the silks. Clipped silks can significantly reduce the amount of successful pollination.

Soybeans are starting into pod development. At this time of year, insect pests like stink bugs and bean leaf beetles can cause pod and seed damage, which directly impacts yields. The forecasted hot and dry weather will be favorable for large populations of spider mites showing up in fields.

This is an important time of year to have adequate moisture, for corn, soybeans, and alfalfa. Corn and soybeans need adequate moisture for complete ear and pod fill, respectively. After recent cuttings, alfalfa fields are slow to put on significant regrowth, which can lead to concerns with potato leaf hopper feeding.

Vegetable Crops

We are still continuing to find new infections of downy mildew, and increasingly more frequent in younger plantings of cucumbers. It is highly recommended to treat your cucumbers for downy mildew, especially in plantings where harvest is not expected to start for several more weeks.

Powdery mildew is slowly but surely spreading onto more area pumpkin patches and squash plantings. If you have plantings of squash that you are done picking in, it would be best to terminate these plantings to reduce the amount of inoculum that is present, especially if younger plants are nearby.

A lot of area growers are still struggling with bacterial diseases in tomatoes and peppers and root rots like pythium and phytophthora in pepper plantings. The warm and damp conditions that we experienced during July are partially to blame for rapid onset of many of these diseases. Hot and dry weather, however, can help to slow the spread of bacterial diseases.

Small Fruit and Orchards

We are finding Spotted Wing Drosophila in the traps that we have set out in peach blocks. While peaches are not a preferred host for SWD, some damaged and infested fruit can still occur. To the best of your ability as a grower, it’s a good practice to pick frequently and keep the ground around the trees clean. Culled fruit provides a food source and suitable habitat for many pests and diseases and removing the cull fruit can help prevent or reduce the severity of issues. Codling moth counts continued to increase this week. Oriental fruit moth counts in our traps continued to decline. In grapes, we are finding consistent catches of the grape berry moth.

Wayne County IPM Notes from July 26 – July 30

Agronomic Crops

Now is the time to scout for stink bugs in corn and soybean fields. At this time, the corn we are scouting is between the R1 and R3 stage. Soybeans are consistently around R1 and R2. Stink bugs can cause kernel damage in corn and pod damage in soybeans. Scouting along field edges will help you find stink bug populations, as they begin infesting fields from the edges and work their way inward.

In our scouting of sunflowers, our IPM team found what we determined to be bacterial stalk rot of sunflower. The stalks were very easy to push over, raising concern for lodging. The center of the stalk, about a third of the way up the plant, had become very soft, rotten, and thus lost all structural integrity. Unfortunately, there is nothing that can be done this year about the stalk rot, however, a rotation of at least 4 years away from sunflower, combined with good weed control, can help to break up the disease cycle and prevent any residue or other plant species from over wintering the pathogen.

Vegetable Crops

Septoria leaf blight is beginning to work its way up tomato plants in the area. This fungal foliar disease, over time, can result in significant loss of foliage and over all a reduction in productivity and longevity of the plant.

Cucurbits are facing a lot of disease challenges right now, including powdery mildew, downy mildew on cucumbers and cantaloupe, and plectosporium. While we consistently see both the mildews, plectosporium can be a little more sporadic and when it occurs, it can cause significant yield loss if left uncontrolled.

The only major issues we have identified this week in terms of insect pests was the continuation of flea beetles feeding on very young cole crop transplants. Make sure you do not allow flea beetle populations to get out of hand.

Small Fruit and Orchards

Codling moth activity has increased in many of the orchard where we have traps set. Overall, though, the apple crop looks very abundant and healthy this year. In peaches, we have started finding spots of bird damaged fruit, as well as damage from Japanese beetles. Our IPM program has put out a SWD trap in some peaches to keep an eye on the SWD populations in peach blocks. In small fruits, Japanese beetles continue to be the main pest of concern as the season begins to wind down. In grapes, we did find some grape berry moth adults in our traps and encourage anyone with grapes to keep an eye out for the grape berry moth adult, or damage to the grapes from the larva.

Wayne County IPM Notes from the Week of July 19 – 23

Agronomic Crops

Rapid crop growth and development is a common sight around the area in corn and soybean fields. The majority of corn fields have tasseled

Alfalfa field in bloom.

and are beginning to silk. Soybeans are flowering and pod development is starting to occur.

We are beginning to find some foliar diseases affecting corn fields, as well as the continuation of insect damage from flea beetles, grasshoppers, armyworm, and several other pests. Soybeans are still being fed on by a wide variety of foliar pests. Our focus will start to shift to pod feeding pest, such as stink bugs and bean leaf beetles. Read more on Corn and Soybean management decisions.

Potato leaf hoppers are remaining consistent in population in alfalfa fields. We are seeing populations either at or below threshold. Some fields have cases of leaf spot; however, we are not seeing any fields with any severe infections at this time.

Vegetable Crops

Powdery mildew found on a cucurbit plant in a Wayne County field.

The Vegetable Pathology Lab at OARDC has confirmed several more cases of downy mildew, on both cucumbers and cantaloupe. It is important to take steps to either protect your crop or stop the spread of any ongoing infections. Powdery mildew is also spreading rapidly through the area. Although some heavy rains may have slowed its spread, favorable conditions have led to some fields rapidly becoming infected.

Flea beetles feeding on young green cabbage plants.

Bacterial diseases continue to spread in pepper and tomato plantings. Pay close attention to these crops in particular, and make sure that you are taking the necessary precautions so as to not spread bacterial diseases. Bacteria can be spread from plant to plant via clothing, equipment, or animals. More from APS

Flea beetles are feeding heavily on recently planted cole crops, which left uncontrolled can cause stunted and underperforming plants. Another insect we have seen quite a few of is the squash vine borer. Although these are not typically going to harm large numbers of plants, they can still be a nuisance, especially in smaller plantings.

Small Fruit and Orchards

 This week we found our first incidence of scab in apples. While this was only an isolated find on a few leaves, it is a good reminder to take some time to scout your apple trees and look for any signs of scab. Oriental fruit moth numbers were significantly above threshold again this week. Japanese beetles were also

Severe damage from Japanese beetles feeding on the foliage of apple trees.

still feeding heavily in many of the fruit crops we scout. Spotted wing drosophila are still being found in all of our traps, and for anyone with small fruit in the area, it is recommended that you treat for SWD.

Wayne County IPM Notes from the Week of July 12th – July 16th

Agronomic Crops

Crop development progressed rapidly in the last week with the abundance of moisture and warm temperatures. Corn plants are either tasseling or nearly there, soybeans have started to flower and overall, there was a lot of new growth.

European Corn Borer and Armyworm found feeding in field corn. The ECB was found feeding on this tassel that has yet to emerge.

Japanese beetles continue to feed in corn, soybeans, and alfalfa. Stink bugs are also out in corn and soybeans, although, stink bugs are more damaging later in the season during ear and pod development, respectively. We are also finding an uptick in worm damage in corn, from both the European Corn Borer and Armyworm.

Potato Leaf Hopper counts were at or below threshold this week. Considering that many alfalfa fields are starting into bloom, we anticipate that fields will be cut before our PLH counts would go over threshold.

Vegetable Crops

Of most importance, the Vegetable Pathology Lab in Wooster confirmed Downy Mildew on a cucumber plot at OARDC. Cucumber growers are highly encouraged to begin taking action to protect their plants, especially as more cases are confirmed around the area.

Japanese beetles are out in force this year and continue to be one of the most consistent insect pests from week to week on a wide range of crops. Other insect pests of note included Colorado Potato Beetles that have migrated off of harvested potato plantings in into tomato and eggplant plantings. In squash, we have still been finding quite a few squash bug egg masses. Squash Vine Borers have also been spotted in some area pumpkin plantings.

Colorado Potato Beetles feeding on a tomato plant. Tommy Becker photo.

During these heavy rains, we have noticed a significant amount of soil splashed up onto the plants and fruit. This will likely encourage more disease incidence. Accordingly, take extra time and care to scout your crops in the coming weeks.

Sweet corn pests like corn ear worm and European corn borer are not showing much activity in our traps. We occasionally find damaged tassels from ECB feeding, however, we have yet to have any fields go over the 10% damage threshold.

Small Fruit and Orchards

 Between last week and this week, we have seen a sustained flight of oriental fruit moth in area peach blocks as our traps have been well over threshold for the last two weeks. Our codling moth traps still do not show much activity.

Over ripe Lodi apple that had spilt following a heavy rain.

We did find some interesting things while scouting apples this week, including blister spot on some “Delicious” apple varieties and Lodi apples that had burst and fell off the trees due to being over ripe.

As a note for all small fruit growers, all of our traps for SWD in the area are currently catching SWD, therefore, we recommend you treat your small fruit. Pay close attention to the label, especially the REI (re-entry interval) and PHI (pre-harvest interval). Another note for all fruit crops, Japanese beetles are feeding on grapes, apples, peaches, and blueberries. The beetles can do significant defoliation as well as damage to the fruit.

 

Wayne County IPM Notes for the Week of July 5 – July 9

Agronomic Crops

             Potato leaf hopper counts seem to be remaining constant, staying below threshold in alfalfa fields. Other insects, such as Japanese beetles in sweet corn, or grasshoppers in soybeans, are not holding steady, instead, we are seeing increasing population numbers and an increase in foliar feeding activity. Corn fields have seen an uptick in activity and feeding from armyworm.

In some fields, where moisture seemed to be limited due to spotty rain showers, we have started to see some nutrient deficiencies, more specifically potassium. Adequate soil moisture is key to have nutrient uptake through mass flow, and when nutrients like potassium are not taken up in adequate amounts, the effects of lack of moisture can compound.

Vegetable Crops

             High tunnel tomatoes were one of the areas of focus for disease development this past week. Many high tunnel tomatoes are currently experiencing cases of leaf mold. As a side note on high tunnel tomatoes, we did observe a thrips outbreak in a high tunnel, where heavy feeding by the thrips was causing significant discoloration on the foliage and stunting of the plants. Peppers took up the other focus with disease development, mainly due to favorable conditions for bacterial diseases to manifest.

Flea beetles seemed to make a comeback this week. Several fields of cole crops were over threshold for flea beetle counts. Japanese beetles are continuing to feed in the majority of the crops planted in the area. Other insects like squash bugs are starting to be found more frequently, specifically in early planted summer squash.

Sticking with cucurbits, we are starting to find spots of powdery mildew in plantings of zucchini and yellow squash. It is important to scout your crops and look for powdery mildew, especially if you have succession plantings of young cucurbit crops nearby. Powdery mildew is easily spread onto younger plants, so it is recommended that you keep up with spraying for powdery mildew and terminate the older infected plantings once you are done harvesting.

Small Fruit and Orchards

 First and foremost, we have found spotted winged drosophila in our area. The threshold for SWD in small fruit is 1 fly. Since we are now finding adults, we encourage growers to also do salt tests on the berries to check for larvae.

Wooly apple aphids continue to show up in the several apple orchards in the area. These are a tough pest to get under control due to their protective waxy coating.

OFM counts in some peach blocks were above threshold for the first time in several weeks. OFM counts remained well below threshold.