Scouting Reports

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 June 7-11

Agronomic Crops

            Corn and soybeans are both being impacted by slug feeding. In most cases, corn will be able to outgrow the pressure from the slug feeding. Soybeans, however, are much more susceptible to being severely damaged by slug feeding, even to the point of significant crop loss. Slugs are best managed by avoidance and habitat reduction. Slugs thrive in heavy residue fields with minimal tillage disturbance. Later planting dates, when soils start to dry out, along with some tillage or residue management can help to prevent major impacts from slug feeding.

Black cutworm, Matthew Nussbaum photo.

Some corn fields are also being impacted by black cutworms. These caterpillars can do significant damage in young corn stands. We are reaching the end of their feeding activity in our area, but we will continue to monitor for other larva pests. Weed management is also important this time of year in agronomic crops. Being able to knock the weeds back until we start to get some canopy closure can help prevent the weeds from competing with corn or soybean plants for water, nutrients, and sunlight.

Alfalfa fields are showing good regrowth with minimal pressure from diseases or insect pests. There are some concerns with increasing aphid populations, along with the arrival of the potato leaf hoppers.

Vegetable Crops

            The insect pressure on the area vegetable crops has continued without much fluctuation.  In summary, the Colorado potato beetle larvae, along with flea beetles, continue to feed on potatoes, tomatoes and eggplant, we began to find tortoise-shell beetle feeding on the leaves of sweet potatoes, thrips are starting to feed in onions, aphids are continuing to feed in many crops, including peppers and tomatoes, slugs are feeding on sweetcorn, as are cutworms, cucumber beetles are all over cucurbit crops, and potato

Golden Tortoise Beetle on Sweet Potato.

leaf hoppers and bean leaf beetles have started to build population in green beans.

The warm and wet weather has led to some disease concerns, especially in lettuce. We have started to find heads of lettuce being affected by white mold. It is best to remove these heads of lettuce from the field to prevent further infection and soil infestation.

Small Fruit and Orchards

Our trap counts for CM and OFM were either 0, or low this week, with none of our trapping locations being near threshold. Most of the small fruit in our area is in fruit development, or fruit maturity. Strawberry harvest is fully underway at this time. We are seeing some slug feeding on strawberries, but very few other concerns at this time. Grapes are beginning to bloom, and depending on the variety, may already be in full bloom. Don’t forget to spray for black rot during this period.

Wayne County IPM Notes from the Week of June 1- June 4

Agronomic Crops

Emerging soybeans in a no-till field.

Corn and soybeans are emerging and beginning to progress through early vegetative stages. Within the next week or so we will begin doing stand counts and encourage you to do the same. We will also keep an eye out for early season insect and pest problems such as slug damage and bean leaf beetle feeding in soybeans as well as slug feeding, cut worm damage and flea beetle activity in field corn.

In alfalfa most of the fields we are scouting are now in regrowth after first cutting. These second cutting fields have very limited pressure from weevil larvae and overall are relatively problem free. In the coming weeks, we need to be alert with regard to the potato leaf hopper. According to the most recent C.O.R.N. newsletter, potato leaf hoppers are now being found in Ohio alfalfa fields. We plan on starting with sweep net counts this week to determine current populations of PLH in our area fields.

Vegetable Crops

Cucumber beetle feeding on the foliage of a summer squash plant.

Insects continue to be the main headline in the vegetable crops in our area. Of greatest concern is the cucumber beetle. The populations continue to increase in number and the efficacy of seed treatments or in-furrow applied insecticide starts to decline 4-6 weeks after the seed germinates or after the insecticide is applied. This means that more of the beetles are feeding without being affected by the insecticide. Be sure to scout cucurbit crops frequently and carefully to get accurate counts of the beetles. The thresholds for cucumber beetles are as follows: Cotyledon stage – .5 beetles per plant, 2-4 leaf stage – 1 beetle per plant, greater than 4 leaves – 3 beetles per plant. Limiting the amount of feeding that cucumber beetles do will also limit the amount of bacterial wilt occurring in these plantings. Do be cognizant of the plants that are in bloom and limit your spraying to a time when it will be least impactful on the pollinators.

 

Colorado potato beetle larva feeding on a potato plant. Tommy Becker photo.

Other insects that were spotted this week include Colorado Potato Beetle larvae and imported cabbage worms. Both of these pests can cause significant damage in their respective crops when left unchecked. Flea beetles also continue to feed on plantings of cole crops, preferring young transplants versus older, more established plantings, although both should be inspected for beetles.

Sweet corn plantings are growing quickly and some plantings that were done into plastic mulch and covered this spring already have a few tassels poking out. Overall, there has been no major concerns in the sweet corn plantings so far, however, do your best to keep up on weed control. Weeds such as bindweed, thistle, and ragweed can not only compete for resources, but can also make harvest difficult and may serve as refuge locations for insect pests to retreat to.

Small Fruit and Orchards

We are beginning to enter a critical period for managing diseases in grapes. This period, which extends from immediate pre-bloom through four to five weeks post bloom, is a critical time to control fruit infections by the pathogens which cause black rot, powdery mildew, and downy mildew. According to the 2021-2022 Midwest Fruit Pest Management Guide, the fruit of the most commonly planted varieties becomes resistant to infection by these diseases by four to five weeks after bloom.

In strawberry plantings we are seeing a lot of green fruit and in some locations, harvest is beginning to ramp up. Overall, there have been very few concerns in the

Blueberries starting to enter the “fruit coloring” stage.

strawberries to this point, with just a few slugs here and there and a spotting of powdery mildew on a few plants. Powdery mildew is managed by spraying either pre-bloom or during the early bloom through bloom stage.

Other small fruit like blueberries and brambles look to have a heavy fruit set this year. Blueberries are beginning to get some color to them, and the blackberry and raspberries are either in bloom or in fruit development.

In apple and peach orchards, the fruit are noticeably starting to increase in size. We are finding some aphids in apple trees, feeding on the leaves and new shoots. In peaches, we did find a few instances of powdery mildew affecting the fruit. Trap counts for OFM and CM were under threshold in all of our traps this week. The counts are down after last week with several orchards above threshold for CM and OFM counts.

Wayne County IPM Notes from May 24th – May 28th

Agronomic Crops

Parasitic wasp cocoon, easily identifiable by the gold ring around the center of the cocoon.

Alfalfa fields are currently at various stages of growth and development, as well as mixed between first and second cutting. Our scouts are keeping an eye out for the arrival of the potato leaf hopper while still consistently scouting for the alfalfa weevil larva. Interesting to note with regards to the alfalfa weevil larva, we have been finding increasing numbers of parasitic wasp cocoons. These wasp prey on the larvae and in large enough numbers help to manage larvae populations.

Corn was spiking in a few fields, and yet to emerge in others. We have not yet observed any emerged soybeans in our scouting, although, we anticipate that many fields will be planted and emerged in the next week or so.

Vegetable Crops

            This week proved to be ideal conditions for a lot of insect pests to find their way onto various vegetable crops. In cucurbits, we began seeing an increasing number of cucumber beetles. These populations should be monitored closely, especially as early plantings are flowering, and likely growing out of

Aphids feeding on Pepper leaves.

any seed treatment, and new transplants are being planted.

Aphid populations in crops such as peppers and tomatoes rapidly increased within the last week. We saw firsthand very significant populations of aphids feeding on these plants, as well as others. Make sure to scout carefully for aphids, as left unchecked can rapidly multiply and given enough time, can stunt young transplants due to their feeding.

Flea beetles were active in cole crops again this week. They were also feeding in potatoes and eggplant plantings as well.

Many vegetable transplants that were planted within the last week or so experienced transplant shock and heat stress, especially if planted into black plastic on hot, sunny days. Most of these plants will be fine but may look poor or stunted for a period of time.

Aphids feeding on Tomato leaves, Tommy Becker photo.

Small Fruit and Orchards

            In apples and peaches, insect activity seems to be picking up. Codling moth trap counts in apple orchards this past week showed small increases, whereas the Oriental Fruit Moth traps in peach orchards show the most rapid increase. In the southern end of our scouting range, our counts were over threshold. Also in peaches, we have detected increased activity from both the lesser and greater Peach Tree Borer.

Guttation on a strawberry leaf, Tommy Becker photo.

Strawberries are coming into production. Early season, or high tunnel berries have been in harvest for the last week or two, with relatively problem free berries, other than the occasional slug or two. We still have yet to find any significant number of thrips in strawberry blossoms, often finding none, or just a single thrips in a bloom.

Other small fruit, like blueberries, are in fruit development. Brambles are either in bloom or have some fruit starting to develop.

Grape shoots are extending, and the plants are nearing the immediate pre-bloom stage. This is a critical time to be spraying to manage black rot.

Wayne County IPM Notes from the Week of May 17th – May 21st, 2021

Agronomic Crops

Cut alfalfa field in Wayne County.

The weather was very cooperative this week and a lot of forages were cut, and field conditions were right to either get fields ready to plant or start to get seeds in the ground.

In the interest of alfalfa growers, we have been paying close attention to the alfalfa weevil larvae and their development. The weevil larvae are forming cocoons and pupating.  Typically, we only experience a single generation of alfalfa weevil per season, however, given the early development and continuation of above average temperature, there is the chance of seeing a fairly substantial 2nd generation. This is problematic for a few reasons. First off, if we continue to see hot and dry conditions, that in itself will stunt regrowth on cut alfalfa. Additional feeding by young 2nd gen weevil larvae on stressed alfalfa regrowth can either severely delay 2nd cutting or if the infestation is significant enough, total loss of 2nd cutting.  Typically, by this point in the year, we begin to move on from alfalfa weevil scouting and turn our attention to the Potato Leaf Hopper, however, this year we may be dealing with both at the same time.

We are not yet scouting any corn or soybeans; however, we expect that we will begin to see more of those acres planted and have relatively rapid germination due to increasing soil temperatures. A few timely rains can help to push these crops germination as well. Soil temperature and GDD Accumulation

Vegetable Crops

             As we move into warmer temperatures, it would be best to remove row covers from field planted crops in the interest of pollination and reducing heat stress. In crops that do not need pollinated such as cole crops, the row cover can serve as an insect barrier and prevent early infestation from the Imported Cabbageworm. Crops such as summer squash, cucumbers and tomatoes

Flea beetles feeding on a recently transplanted brassica plant.

all need to be uncovered sooner than later to avoid poor pollination and subsequently, poor fruit set.

Hot weather can also be problematic when transplanting into black plastic. The black plastic can become very hot and planting a young, tender transplant into the plastic on a hot, sunny day can cause a significant amount of stress, burns on the leaves and stems and in some cases, death of the transplant. Try to plant in the evenings, as temperatures cool down or on cloudy, cooler days.

Colorado Potato Beetle adults on a potato plant.

In the last week we have seen an explosion of flea beetle in cole crops, and the Colorado potato beetles have begun to make their way into potato plantings. Frequent scouting and monitoring of these insect pests is extremely important. Large populations on young plants can stunt their growth and reduce yields. Conditions have been ideal for rapid population increases, hence the need for frequent scouting. An interesting insect problem we observed was a planting of cole crops where the roots of some plants were being destroyed by ants. In most cases, as you turn on your irrigation lines under plastic, it will drive the ants elsewhere.

Generally speaking, disease pressure has been very low in vegetable crops to this point. We have observed some early blight in a tomato high tunnel, as well as blossom end rot in high tunnel tomatoes.

Small Fruit and Orchards

            Apples and peaches are both reaching fruit development. There was significant growth and change in the size of the fruit over the past week. Out of all of

Strawberry blooms with black centers, damaged by freezing temperatures, alongside healthy blooms.

the orchard traps that we have out, we caught 1 OFM and 1 CM. We began to find aphids in apple orchards. The feeding was evident by curling leaves and shoots.

Blueberries are in petal fall and are setting fruit. Raspberries are getting ready to bloom and overall seem to be coming along just fine.

 

Grape bud that had been damaged due to freezing temperatures now showing secondary growth. Tommy Becker photo.

Strawberry varieties that were early to bloom, and left uncovered, likely suffered heavy bloom loss due to the freezing temperatures that we experienced. Some early blooming varieties had very few, if any, healthy looking blooms. Many plants have put on new blooms, which are very easy to distinguish from the frosted blooms. Early varieties of plasticulutre strawberries that were covered and protected from the cold are setting fruit and beginning to ripen and may even be in harvest. We are not finding any thrips at this time. Unfortunately, we are finding a lot of slugs in strawberry plants and on the berries.

Currently, grapes are now past the bud burst stage, as most are at the 4-8” shoot stage.  We are beginning to see where grape buds that had been damaged due to freezing temperatures are putting out secondary buds and shoot growth, which is very promising.

Wayne County IPM Notes, May 3-7, 2021

Agronomic Crops

Mycelial growth on the crown of an alfalfa plant due to infection by Sclerotinia Crown Rot.

Generally speaking, the crop that we are most interested in at this point of the year is alfalfa. The corn and soybeans may have been planted, and in some areas, may be starting to emerge. The main concern in alfalfa in terms of insect pests is the alfalfa weevil. This year, it is especially problematic due to increased GDD accumulation. The early warm temperatures pushed us to about two weeks ahead of where we were last year in terms of our accumulated heat units. This is reflected in the progression of the alfalfa weevil, not only in size, but in number. Most fields were not over threshold, but certainly showed weevil damage and the weevils that were feeding ranged from 1st to 3rd instar.

While scouting alfalfa fields, its important to inspect the entire plant. The prolonged cool and wet weather that we have been experiencing has been perfect for development of Sclerotinia crown and stem rot in alfalfa and clover fields. It can be easy to confuse this disease as winter kill, but further inspection of the plant, especially near the crown can reveal white, mycelial, cotton like growth. You may also find sclerotia in or on the stems and crown. Once the weather warms up and fields dry out, this disease will likely stop progressing, and some infected stands may recover and produce sufficient yields in subsequent years. Keep in mind that those sclerotia will remain in the soil for many years waiting for perfect conditions to start the disease cycle again.

Vegetable Crops

            With the cold temperatures extending into our early growing season many growers with high tunnels are using heat sources such as wood burners and gas stoves to keep their high tunnels warm. If you are doing this, please make sure your vents are clear and that all of the exhaust, fumes and smoke are making their way out of the tunnel. Double check to make sure chimney pipes are snug and the joints are not loose. Plants, especially tomatoes, are very sensitive to ethylene gas, a by-product of burning and when the smoke or fumes from the stoves are making it back into the tunnel, the plants are exposed to the ethylene for prolonged periods of time. Plants exposed to ethylene will show signs of epinasty, or a downward spiral of shoots and curling leaves, as well as blossom abortion.

Epinasty in tomato due to ethylene exposure.

Other than vegetables in high tunnels, some cole crops and lettuce are planted. Onions and fall planted garlic are also handling this cool wet weather with relative ease. As a word of caution, wet soils and cold temperatures do not equate to great growing conditions for both transplants and direct seeded crops. Some crops handle it much better than others. For crops like summer squash, peppers, and tomatoes, it would be wise to hold off for a bit longer be fore attempting to get them in the ground.

Small Fruit and Orchards

            Apples are at petal fall. Peaches are at petal fall and, in some cases, shuck split. No CM or OFM concerns at this point in the orchards. We did observe some frost or freeze damage on some apple blossoms, but there are more than enough healthy blossoms to cover any loss from the freeze that occurred.

Blueberries are in full bloom and have no concerns at this time.

 

Strawberry bloom with a dark center. The dark center is the dead part of the bloom that would grow into the berry.

Strawberry varieties that were early to bloom, and left uncovered, likely suffered heavy bloom loss due to the freezing temperatures that we experienced. Some early blooming varieties had very few, if any, healthy looking blooms. They will still put on new blooms, but do not expect large yields from early season strawberries.

Grapes also experienced some damage due to the cold temperatures. Currently, grapes are around the bud burst stage. Some buds that were exposed to the cold have died; others look damaged. In another week or so, we will be better able to tell the extent of the damage that occurred to the grapes.

Wayne County IPM Notes from September 20-26

Wayne County IPM Notes

(From the Week of September 20 – September 26)

Frank Becker, OSU Extension Wayne County

Vegetable Pests

Aphids feeding on pumpkin leaves. F. Becker photo.

Cucurbit growers need to check their crops for infestations of aphids. Large populations of aphids can be found feeding on the underside of leaves. While the feeding on the foliage is not of major concern at this point in the growing season, the exudate from the aphids is. Aphids secrete a sticky substance known as honeydew and when large amounts of the honeydew are being formed, it can drip down onto the pumpkins and result in black sooty mold growing on the fruit.

Continue to keep watch over late season cole crops as there are still a lot of imported cabbageworm adult butterflies in and around crops such as broccoli, cabbage, brussels sprouts, and cauliflower. Additionally, other fall insect pests such as the cabbage looper and aphids can become problematic. Aphids can have rampant infestations during cooler and dry weather.  Therefore, routine scouting, especially at this time of year, is important to effective pest detection and management.

Imported cabbageworm larva feeding on cole crop leaves. F. Becker photo.

Fruit and Vegetable Diseases

Residue management of fruit and vegetable crops is an important component of integrated disease management. Typically, at the end of the season, plants are commonly being affected by a range of diseases. As management of these diseases dwindles towards the end of the season, there is an increased level of inoculum that may be able to over winter. Many of the pathogens affecting the plants now are able to over winter and result in disease challenges again next year. It is important to know what diseases you have in your fields. This knowledge can help you make crop management decisions such as how long to rotate out of a certain crop. Additionally, the residue that is left at the end of the season should either be composted or tilled into the soil as soon as possible. Composting or incorporating the crop residue allows for the plant to be broken down by soil microorganisms and prevents the spread of the pathogen to other plants that may be alternative hosts that could overwinter the pathogen. Doing this in association with crop rotation will help give time for the pathogens to die off. Typical crop rotations allow for 3-

A field that has been cleared of plant debris, run through with a disc and then planted with cover crops. F. Becker photo.

4 years between planting a crop in the same family.

Fruit Pests

Stink bugs are still active and can be found along wood-lines and field edges. Although, numbers do seem to be dropping as the summer comes to an end. I am still finding the occasional fruit that has been damaged by a stink bug. The damage is typically occurring in trees along the edges of orchard blocks, especially near wooded areas.

Wayne County IPM Notes from September 13 – September 19

Wayne County IPM Notes

(From the Week of September 13 – September 19)

Frank Becker, OSU Extension Wayne County

Vegetable Pests

Large masses of cucumber beetles on pumpkin plants late in the season. F. Becker photo.

Cucumber beetles continue to have high populations in pumpkin fields. The spotted cucumber beetle, which is also the southern corn rootworm adult, are migrating in masses out of corn fields as corn silks dry down and finding their way into pumpkin fields. So long as the beetles are not chewing on the skin of the pumpkin, they are not anything to be concerned about, however, once they start damaging the skin of the fall vine crops, an insecticide application may be warranted.

Scouting your latest plantings of cole crops is recommended to make sure that cabbageworms do not get out of hand. It can be easy to let your guard down as the season winds down, but if you want to have a marketable crop, you need to keep an eye out for the imported cabbageworms doing damage.

Vegetable Diseases

Peppers, at this point in the season should be winding down, however, disease pressure can force a premature end

Anthracnose lesions on a bell pepper. F. Becker photo.

to the season quite rapidly. One disease that can cause a rapid decline in peppers is anthracnose. At this point in the season, it is not worth the investment in any fungicide applications. For future planning, practice a three-year crop rotation with crops that are not in the Solanaceae family and consider doing seed disinfestation before planting. This disease can be managed with fungicides; however, it is important to address the issue of the origin of the diseases, rather than trying to fix the issue by applying a rescue fungicide every year.

At this point in the season, it is of your best interest to consider the cost of any fungicide application in respect to how much more you expect to get out of a crop. With pumpkins, for example, as the plants are beginning to die off at this point in the season, it is not likely that any fungicide application will be effective or result in any increase of yield or crop value. For a crop like cole crops that are just a few weeks in the ground, then you may have opportunity to apply fungicides, should the need arise. As always, follow the label and pay close attention to the pre-harvest interval when applying a fungicide.

Fruit Pests

Stink bugs are still active and can be found along wood-lines and field edges. I am still finding the occasional fruit that has been damaged by a stink bug. The damage is typically occurring in trees along the edges of orchard blocks, especially near wooded areas.

Fruit Diseases

Apples are now ripening and being harvested in orchards around Wayne County. F. Becker photo.

As fruit continues to ripen and be harvested, we continue to move forward through the growing season without many disease issues in our area. If you are doing any final treatments for fruit diseases, pay close attention to the PHI on the product label. The pre-harvest interval determines how long after you applied that product that you may harvest the crop. This is especially important to pay attention to as many varieties of orchard crops as well as grapes are maturing and nearing harvest.

Wayne County IPM Notes from September 6 – 12

Wayne County IPM Notes

(From the Week of September 6 – September 12)

Frank Becker, OSU Extension Wayne County

Vegetable Pests

After seeing the adult butterflies flying amongst cabbage, kale, and broccoli plantings for the past week or so, I am now finding imported cabbageworms feeding on these plants. Scouting your latest plantings of cole crops is recommended to make sure that these worms do not get out of hand. It can be easy to let your guard down as the season winds down, but if you want to have a marketable crop, you need to keep an eye out for the imported cabbageworms doing damage.

Corn earworm numbers continue to increase in our traps in Wayne County, as well as across the state. Since late planted sweet corn has green silks and is an attractive crop for the moths to lay their eggs on, we typically see an increase in moths this time of year in, or near, sweet corn plantings. This time of year, field corn may be responsible for the large increase in moths, as the lack of green silks leads them to find alternative sites to lay their eggs.

Vegetable Diseases

            At this point in the season, it is of your best interest to consider the cost of any fungicide application in respect to how much more you expect to get out of a crop. With pumpkins, for example, as the plants are beginning to die off at this point in the season, it is not likely that any fungicide application will be effective or result in any increase of yield or crop value. For a crop like cole crops that are just a few weeks in the ground, then you may have opportunity to apply fungicides, should the need arise. As always, follow the label and pay close attention to the pre-harvest interval when applying a fungicide.

Fruit Pests

All of the traps out for codling moth and oriental fruit moth continue to decline, and in some cases are dropping to no moths being found in the traps.

Stink bugs are still active and can be found along wood-lines and field edges. I am still finding the occasional fruit that has been damaged by a stink bug. The damage is typically occurring in trees along the edges of orchard blocks, especially near wooded areas.

Fruit Diseases

            As fruit continues to ripen and be harvested, we continue to move forward through the growing season without many disease issues in our area. If you are doing any final treatments for fruit diseases, pay close attention to the PHI on the product label. The pre-harvest interval determines how long after you applied that product that you may harvest the crop. This is especially important to pay attention to as many varieties of orchard crops as well as grapes are maturing and nearing harvest.

Wayne County IPM Notes for August 30 – September 5

Wayne County IPM Notes

(From the Week of August 30 – September 5)

Frank Becker, OSU Extension Wayne County

Vegetable Pests

Various sizes of stink bug nymphs in the leaf litter of fall vine crops. F. Becker photo.

With daytime high temperatures becoming cooler, we are starting to see more and more activity from the squash bugs. If you are actively harvesting your fall vine crops, the squash bugs may not be of concern to you. However, if you are not yet harvesting or choosing to leave your fall vine crops out in the field, the squash bugs can and will do damage to the skin of the pumpkins and gourds. The best time to scout your fields to look for squash bugs is early in the morning or into the evening when they are not in direct sunlight. More on squash bug management.

Cucumber beetles have made a late season come back, much to the dismay of many fall vine crop growers. The cucumber beetles, this late in the season, tend to do very little damage to the foliage of the plants. What they do go for is the fruit instead. Beetles will damage the skins of pumpkins and gourds. This leaves the pumpkins and gourds as less desirable crops and also opens them up to infection and secondary insect pests that would otherwise not affect the fruit.

Late season damage being done by cucumber beetles. F. Becker photo.

Stink bugs are out and doing damage to crops such as tomatoes. The stink bugs activity and feeding starts to increase most noticeably from late July through August and they remain active through the end of the growing season. Their damage on green tomatoes may appear as small, whiteish areas. On ripe tomatoes, the damage shows up as a golden yellow “starburst” pattern. While this damage is typically only cosmetic, higher amounts of feeding can result in infection and result in the fruit being unmarketable.

Vegetable Diseases

Plectosporium blight on pumpkin can cause significant crop losses. The disease typically presents itself as diamond shaped lesions on the stems and can also affect the veins on the leaves, although it can infect all parts of the plant. The lesions start out small but can quickly cover the entire stem. This disease has started to show up within the last few weeks in Ohio due to the favorable conditions of rain, and cooler temperatures.

Plectosporium blight lesions on a pumpkin stem. F. Becker photo.

A common thing to see in pumpkin fields as plants are maturing is yellowing leaves and the leaves starting to die back. Although there may be diseases such as powdery mildew present in the field, this rapid deterioration is not likely solely the result of the disease pressure and rather the natural senescence of the plant. As the plant matures and the pumpkins and gourds begin to cure, the plant has essentially reached the end of its life cycle. The leaves begin to change from dark green to a pale green/yellowish color and will eventually begin to die back. So long as this is happening at the end of the season and the pumpkins and gourds are mature, there should be no concern.

Fruit Pests

Spotted wing drosophila have been active in small fruits for some time, but with peaches now being harvested, the SWD can and will target the peaches as well. I have found peaches that have SWD larva feeding just under the skin. SWD can also do damage to grapes. I have started to find berries in grape clusters that were soft or looked poorly. Just under the skin of these grapes I found SWD larva feeding and moving around. Many grapes are ripening and getting close to harvest so anyone with grapes should consider treating for SWD.

Stink bugs can also do a lot of damage to fruit crops this time of year. I have set out traps and they are already showing very active stink bug populations. I am also finding damage from stink bugs in orchard crops. Most of the damage I am finding has been occurring in apples. This damage appears as a discolored depression in the skin with corking of the flesh all the way up to the skin. This damage can occur anywhere on the apple, although it can be frequently found on the “shoulder” of the fruit.

Fruit Diseases

Overall, disease pressure has been fairly limited this year. Hot and dry conditions have prevented favorable conditions needed for disease development. As fruit continues to ripen and be harvested, we continue to move forward through the growing season without many disease issues in our area. If you are doing any final treatments for fruit diseases, pay close attention to the PHI on the product label. The pre-harvest interval determines how long after you applied that product that you may harvest the crop. This is especially important to pay attention to as many varieties of orchard crops as well as grapes are maturing and nearing harvest.

Apple that has cracked and split after a heavy rain following drought conditions. F. Becker photo.

After this recent round of heavy rain and subsequent heat and high humidity, apple growers should be aware that some apples may crack or split while still on the tree. We are fortunate that we were beginning to have some more frequent rains that were starting to alleviate drought conditions, and this prevented rapid uptake from the trees. Typically, when a heavy rain occurs after prolonged dry spells or during drought conditions, there is large amounts of moisture taken up through the roots as well as absorbed through the skin of the fruit. This results in rapid cell expansion and thus cracking, and splitting occurs.