Scouting Notes

Wayne County IPM Notes From the Week of June 21-25

Agronomic Crops

            This week was a good week for crop growth and development. We are now seeing V6 to V8 corn and soybeans reaching V2-V3 in most

Northern Corn Leaf Blight lesion on a corn leaf.

areas. As the crops continue to progress, they become more tolerant of early insect pests like cutworms and slugs. Overall, there are not many concerns with our agronomic crops at this point in the season. We are, however, starting to see the arrival of some more common summer pests.

Japanese beetles have started to make their presence known in corn and soybean fields across the area. We are also finding an increasing number of grasshoppers, especially in soybean fields. This week we also noted our first sighting of Northern Corn Leaf Blight.

In alfalfa, we have not observed any large counts of potato leaf hoppers to this point. There are a few out there, but nothing has been over threshold so far.

Imported cabbage worm eggs in the red circles and a recently hatched caterpillar circled in yellow.

Vegetable Crops

            Imported cabbage worm butterflies are laying a lot of eggs on cole crops. It is important to scout the crops for the eggs as well as the larvae, in order to have a better grasp on when the larvae are hatching and causing damage. This will also help ensure efficient and timely insecticide applications.

Aphids are continuing to be present in many of the vegetable crops that our IPM program scouts,

Thrips feeding in on onion leaves in the center of the plant.

however, we are finding a lot of beneficial insects that are feeding on the aphids and helping to either maintain or eliminate populations. Japanese beetles also are present now in many of the crops in our area.

This week was also the first week that we really noticed an increase in thrips in onion plants. As the leaves get larger and offer more shelter for the thrips, the populations are able to multiply rapidly.

Some sweet corn in the area is tasseling, silking and in some cases, nearing harvest. We have noted some European Corn Borer feeding in tassels. If 10% of silking plants are damaged by ECB, a treatment is warranted. In some fields, this threshold was met, and growers started on a spray program for their tasseling and silking corn.

Small Fruit and Orchards

Aphids in the apple trees continued to be the main pest this week. We found more clusters of wooly apple aphids, which are now working their way out onto the new shoots and green growth. Our trap counts for OFM remain well below threshold.

OFM traps in peach blocks were also well below threshold, however, we did see an increase in the trap counts of Greater and Lesser Peach Tree Borer.

Strawberry season is winding down. Our SWD traps in strawberry patches yielded 0 SWD. Harvest is starting in some area blueberry and bramble patches. Grape clusters are developing nicely and starting to put on some size.

Wayne County IPM Notes From the Week of June 14-18

Agronomic Crops

Bindweed wrapping up a corn plant.

The corn planted in our area is really starting to outgrow any early concerns that may have been had regarding insect pressure. The corn is also out growing many of the competing weeds, however, it is still recommended to do what you can to reduce the weed pressure on the corn plants. Soybeans also have seemed to escape most of the insect pressure; however, we are now seeing large areas of heavy feeding from deer and groundhogs.

We noted in our scouting this week on the large amount of 2nd cutting alfalfa coming off. 2nd cutting came and went without many concerns, and very limited pressure from insects. We will continue to scout for potato leaf hoppers, especially on the regrowth after 2nd cutting.

Vegetable Crops

            This growing season, so far, has been all about the bugs. We have not had a huge amount of disease pressure

Squash bug eggs on summer squash.

on the vegetable crops in our area. We have, however, continued to find more insects impacting local crops.

Newly spotted insect pests this week included Japanese Beetles, thrips, and squash bugs. The Japanese Beetles were found in silking sweet corn, the thrips are being found in onions and the squash bugs are being found laying eggs in summer squash plantings.

 

Japanese Beetle found in a sweet corn stand.

In green beans we are still seeing a light population of potato leaf hoppers and a few bean leaf beetles feeding here and there. Cucurbits still have some cucumber beetles feeding, as well as some aphids. Aphids are not picky about which crops they are in, as we continue to find them in a variety of crops, including peppers and tomatoes. Both eggplant and potatoes are dealing with flea beetle and Colorado potato beetle. The Colorado potato beetle larva are becoming very prolific in some areas and causing significant defoliation. Cole crops, while also dealing with pressure from flea beetle, are now seeing an increase in activity from the imported cabbage worm caterpillar.

Small Fruit and Orchards

Aphids and mites are being found in fruit trees, primarily apple trees. This week, we began to find European red mites, green apple aphids and wooly apple aphids. Trap counts for CM in apples and OFM in peaches were all below threshold, with many traps reporting zeros.

The biggest update in our pest outlook in small fruit was not an insect, instead it involved birds. There was bird damage being found in strawberries, as well as in blueberry areas where the berries are starting to color. Some growers are using netting to exclude the birds from blueberry plantings. This is a lot of work but saves a lot of berries from being damaged.

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 for the week of May 10 – May 14

Agronomic Crops

            This week again, we saw sustained activity and feeding from the alfalfa weevil. At this point, we have started to observe some of the weevil reaching later stages of development and beginning to pupate. In cases where there is a poor alfalfa stand, the weevil damage is more severe as compared to feeding in a full, healthy stand.

Alfalfa weevil cocoon. Tommy Becker photo.

            As the alfalfa continues to grow taller, we also noticed some lodging where after heavy rains, the alfalfa began to lay over. This is not a major concern, but just something to be aware of.

            While driving around the county, we did observe some corn fields that were planted, and the corn plants are beginning to emerge. In our travels we did not see any soybean fields, although, we have heard reports of some soybeans emerging as well.

Vegetable Crops

            Remember to keep your high tunnels ventilated and not too wet as not doing so can lead to conditions that can create the perfect environment for diseases. As such, we began to observe high tunnel tomatoes with early blight. Low humidity, consistent air movement and proper plant spacing can all help to avoid experiencing certain foliar and root diseases.

Early flea beetle feeding on young cole crops.

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 before attempting to get them in the ground.

We did note some frost damage to potatoes that were emerging. We also spotted some flea beetles on cole crops this week.

Sweet corn that was planted early is somewhere around the V2 mark, standing about 3-4” tall. Given some warm temperatures and sunshine, the corn will really take off.

Small Fruit and Orchards

            Apples are at fruit development. Peaches are at shuck split. No CM or OFM concerns at this point in the orchards.

Blueberries are in petal fall and are setting fruit. We are starting to see Phomopsis blight in some blueberry bushes.

Ripening “plasticulture” strawberries. Tommy Becker photo.

Raspberries are getting ready to bloom and overall seem to be coming along just fine.

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. Early varieties of plasticulutre strawberries that were covered and protected from the cold are setting fruit and beginning to ripen.

Grapes also experienced some damage due to the cold temperatures. Currently, grapes are around the bud burst stage, and some are at the 4-8” shoot stage. Some buds that were exposed to the cold have died; others look damaged. We are still waiting to see the full extent of the frost damage in many of our small fruit and orchard crops.