VEPART Pest and Scouting Report

Hi all,

This week in addition to the typical cast of [inset pest] characters, we are starting to see an increase in disease incidence across the region. The distribution of disease has been variable throughout the state, owing to the scattered nature of rain and thunderstorms this season.

Thanks to Ann Hazelrigg of the UVM Plant Diagnostic Clinic, we have quite bit of important disease notes to consider:

• As has been communicated several weeks ago, Basil Downy Mildew seems to be rather prevalent in pockets within the state. This fungal-like pathogen blows in from the south and showed up earlier than usual this year. Top of the leaves look sunburned and undersides look dirty, as if dirt has kicked up from the ground. Resistant cultivars may get the disease later, but they are not immune. Be vigilant and promptly remove any plants that you suspect may have inoculant. Once an outbreak takes hold, there is not much can be done. Also, a reminder that the Ag Pest Monitoring Site for basil is a great resource for identifying, reporting, and managing BDM.  If you suspect that you are seeing BDM, please send us a message and/or send a sample to the Plant Diagnostic Clinic here at UVM.

 

• Tomato leafspot diseases (Septoria and Alternaria) are showing up on lower leaves of field tomatoes and outer rows in high tunnels. Cultural controls (e.g staking, drip irrigation, keeping up fertility , etc.) can be effective strategies and may minimize large outbreaks, but a few key fungicide sprays may be warranted mid season to ensure later crops. Dry weather will slow the spread of the disease but with every rain, the fungi will move higher in the plant.

 

• Though we are yet to hear of any confirmed incidence of cucurbit downy mildew in cucumber or melons within Vermont, it is just a matter of time, as it seems to be all around within the region (e.g. MA, NY, CT). This is a very early arrival for DM, in comparison to previous years.

In case you missed it, Meg McGrath of Cornell Cooperative Extension, shared the tips below for identifying CDM. Also, check out Meg’s link to biopesticide options here.

 

“Best time to scout crops for CDM is early morning (before 10).  Diagnostic is the grayish brown fuzz of the pathogen’s spores produced on the underside of the yellow, usually angular (on cucumber esp) leaf spots.  Spores are produced overnight when humid, especially when dewy, and then are released with humidity change in the am.  Growers who contacted me were looking at leaves in afternoon when the spores were gone.  When spores are not evident, put leaf upside down on damp paper towel in a closed plastic bag overnight.  If the spots are due to CDM, fuzz should be evident next morning. “

 

• There have been reports of bottom rot issues in lettuce due to wet conditions and poor air circulation. This is typically caused by rhizoctonia. Watch watering and weed pressure.

A couple important insect pest notes:

• With the recent hot dry spell, onion thrips have begun to take off on several of the farms that we have been monitoring. Typically, consistent rains help to wash the leaf tubes and knock back thrips populations. Overhead watering can mimic this effect and suppress thrips pressure. There is also some evidence that metallic mulch may delay or deter thrips from colonizing allium plantings.

 

• We are beginning to see the second flight of beet/spinach leaf miner within the region. This is a bit earlier from what we experienced the last couple of years. These leaf miners can cause significant marketable damage to chard, beet greens, and spinach. You can check crops for recent infestations, by looking on the undersides of leaves for their conspicuous white eggs. Weed control, especially for common SLM host plants like lamb’s quarter, can play a key role in reducing the likelihood of an outbreak.

As always you can find more details on other pests and diseases at our pest and scouting website.

Thanks to all of the growers that have reached out with there own questions and pest scouting information. All information and questions help us to better serve the needs of the VVBGA community.

Cheers,

Vic & Scott

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	In the upper Champlain Valley, CPB populations are transitioning to pupal stages. While in cooler regions of the state, CPB populations are largely in 3-4th instars, feeding away.
Flea Beetle	Most all brassica crops	Flea beetle pressure is largely a non-issue at this time of the season
Imported cabbage worms Diamondback moth	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Status quo with cabbage moths/butterflies. We’re seeing feeding but outbreaks are mostly tolerable.
Leek moth	Garlic	Adult moths are currently laying eggs in alliums throughout the region.
Mexican bean beetle	beans	Adults are being seen in significant numbers.  We are beginning to see more eggs and some larvae. We suspect that the upcoming week we will see more larvae and damage.
Japanese Beetle	Potatoes, Beans, Basil, etc.	There has been a marked increase in Japanese beetle populations in various crops. Many farmers are reporting that this is a very intense year for JB.  It seems that, in general, we are seeing a lot of pressure from many related scarab beetles too (e.g. oriental beetle, Asiatic beetle, etc.)
Potato Leafhoppers	Beans and Potatoes	Hopper burn is being found in beans and potatoes. Undeniably, beans are being the worst hit.
Striped Cucumber Beetle	Squash/Cucumber	Thus far, on farms that we are scouting, SCB populations seem to be more manageable this season.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	The second flight of leaf miners has begun in the region. Be on the look out for their eggs on the underside of leaves.
Squash bugs	Summer and Winter Squash	We’re seeing a plethora of adults and eggs with summer and winter squash. Most of the egg laying is being seen in summer squash. Nymphs are yet to be seen in any significant numbers.
Squash vine borer	Winter squash	Moths are being found in traps from around the region. We have seen many moths in traps and flying around summer squash plantings.
Swede Midge	Brassicas	We are seeing a lot of early season damage in brassicas. It seems to be earlier than past years to see the amount of damage that we are seeing. This seems to be a consistent trend this year.
Tarnished plant bug	Strawberries	We are seeing a high incidence of tarnished plant bugs in lots of crops this season. This week several farmers have expressed high pressure in fruit crops.

 

 

 

 

 

 

Hi all,

With the middle of the season here and many people harvesting summer veggies, we’re also beginning to see some new stages of pests and the arrival of some diseases.

It is also that time of the year when you can take out that 80’s blacklight for the good of IPM! Yes, we are seeing outbreaks of tomato/tobacco hornworms throughout the region and several farmers are seeing some heavy pressure. One of the more fun ways to scout for hornworms, especially in high tunnels, is to bring out a black-light flashlight at night to spot the typically camouflaged pest on your plants. The cuticle of the hornworm will glow in response to the black-light and you can easily pick them off, as seen here. There are also some native natural enemies of hornworms, particularly the parasitoid wasp, Cotesia congregata, that can help to reduce their numbers. Being sure that there are small flowers consistently around to support the wasp population is a great way to keep the wasps active throughout the season. Research on floral resources has shown that buckwheat is a great choice for C. congregata (and for hover flies!). Wasps feeding on the nectar of buckwheat exhibit longer life spans!

Some other notable new pests and diseases:

Swede Midge seems to be a bit of a problem earlier this season than years past, particularly on the farms that we are scouting in Burlington. We were a bit surprised to find consistent and heavy pressure in cabbage, as it is typically not the most susceptible crop. Because the midge prefers to lay its eggs near the growing tip of brassicas, any of the “flower-head” brassicas (e.g. broccoli, cauliflower, etc.) are typically more vulnerable to larval feeding. Some recent UVM research has shown that even one larva can lead to marketable damage in these crops. As a result, prevention represents an important component of the IPM program for swede midge control. Insect exclusion netting can help to protect crops till flowers (broccoli, cauliflower), buds (Brussels sprouts), heads (cabbage) and/or stems (kohlrabi) can begin to develop.  Our research team is currently studying the variability of SM attractiveness in different kale varieties to explore the potential for the development of a trap crop system. You can see this research and more in our most recent research brief.

There have been several reports of Japanese beetle outbreaks on some vegetable farms. Though Japanese beetles are typically considered a pest of ornamental plants and turf grass, adults can certainly wreak havoc in some important veggie and fruit crops including basil, corn (silks), grapes, asparagus, etc. We’ve even seen some heavy pressure in solanums this year. For organic growers some possible options include neem and pyrethrin products. Also, some growers have sent us pictures of other scarab beetles (e.g. Asiatic beetle) on their farms. The control options tend to be similar for those beetles too.

We reported the presence of squash vine borer in nearby states a couple weeks ago, and now it seems that we are now seeing many SVB flying and laying eggs here in Vermont. As we previously mentioned, the primary sign of SVB is the wilting of squash plants and the presence of tunneling within the vines at the base of the plant. Unfortunately, once wilting is observed, there is very little that can be done to save the plant. Timely sprays or other applications based upon trap counts are a good protectant during flowering and one grower recently shared “as a last resort, [I] injected a mix of pyganic and organic spinosad into the holes where borers entered the crop. It worked and saved the crop. This is not preferable compared to timely sprays but something you can do if you miss spraying.”

Early blight is being reported in high tunnel tomatoes. Infections begin as small lesions, as they grow in size they exhibit a characteristic “bull’s eye” marking. Typically, early blight is sequestered and transmitted from infected plant refuse, solanaceous weeds, contaminated seeds or tubers. The fungal pathogen can then infect the leaves of new plants. Sanitation and rotation are key control tactics for reducing the likelihood of outbreaks.

Finally, we’d also like to acknowledge that all of the scouting, monitoring, data collection, and reporting behind these reports are the result of the hard work of our dedicated undergraduate research team – Gigi Walsh (UVM), Arianna Hee (UC Berkeley), Frieda Kahn (UVM), and Laurel Marshia (UVM).

As always you can find more details on other pests and diseases at our pest and scouting website.

Thanks always for your input and questions throughout the season!

Cheers,

The VEPART team

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	Currently most populations of CPB are dominated by older larvae which are about to pupate or are currently in the ground pupating. The second generation will be emerging in the next week or so.
Flea Beetle	Most all brassica crops	We continue to see flea beetle. However, because most brassicas are larger in size, the relative pressure from flea beetles is low.
Imported cabbage worms Diamondback moth	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We are seeing many larvae and some significant feeding damage in many brassicas. Diamondback moth are also being found in brassicas in both adult and larval stages.
Leek moth	Garlic	The second flight of leek moth has begun! Adult moths are currently laying eggs in alliums.
Mexican bean beetle	beans	Adults are being seen in significant numbers.  We are beginning to see more eggs and some larvae. We suspect that the upcoming week we will see more larvae and damage.
Japanese Beetle	Potatoes, Beans, Basil, etc.	There has been a marked increase in Japanese beetle populations in various crops. It seems like it might be a bad year for these pests.
Potato Leafhoppers	Beans and Potatoes	Hopper burn is being found in beans and potatoes. Though, most of the damage that we are seeing is being found in beans. Some of the pressure can be quite high.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are becoming substantial, and damage is significant, especially in cucumbers and C. maxima varieties of winter squash.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	A few growers have indicated that they are seeing increased damage from leaf miner. We haven’t seen much in our scouting that isn’t a remnant of the early outbreaks.
Squash bugs	Summer and Winter Squash	We’re seeing a plethora of adults and eggs with summer and winter squash. Most of the egg laying is being seen in summer squash. Nymphs are yet to be seen in any significant numbers.
Squash vine borer	Winter squash	Moths are being found in traps from around the region. We have seen many moths in traps and flying around summer squash plantings.
Swede Midge	Brassicas	We are seeing a lot of early season damage in brassicas. It seems to be earlier than past years to see the amount of damage that we are seeing.
Tarnished plant bug	Strawberries	We are stll seeing a high incidence of tarnished plant bugs  in the region, especially in strawberries and now raspberries too!

 

 

Hi all,

This week we are seeing some new insect pests that have begun to inflict damage around the state. Also, some of those pests that have been building in certain crops are now transitioning through their life stages and may be interacting differently with vulnerable crops.

The most important of the new findings for this week are:

• Leek moth are officially beginning their second “flight” of season. We are seeing modest numbers of adult moths in our baited traps. This is a clear indicator that adults are currently laying eggs on available alliums. In a week or two the LM caterpillars will begin feeding on the upper green leaves of plants. Their characteristic “window-paning” damage can be easily identified from a quick inspection. Onions tend to be relatively tolerant of LM feeding and can withstand quite a bit of damage before any yield loss is seen. However, bulb damage can sometimes occur during curing, as larvae or eggs may be brought into storage/curing areas after harvest. Topping of bulb alliums (e.g. onions, shallots, etc.) prior to curing has shown to be an effective strategy for preventing incidental larvae from contaminating storage areas.  

 

• Mexican bean beetle adults are being found in bean crops within the region. We are mostly seeing adults mating and feeding within plantings. Some egg masses are being laid, but we haven’t witnessed any extensive larval feeding…yet. The bean beetle can be easily mistaken for the lady-bird beetle, as they are closely related. So be sure that you are correctly identifying them! If they get out of hand, they can be quite a pain. The parasitic wasp, Pediobius foveolatus, is a commercially available biological control that has shown to be a relatively effective if its release is correctly timed with the larval generation. You can find more information here.

 

• Colorado potato beetle populations are being found in high numbers in most solanum crops. Many of the now pinkish and plump larvae are just about ready to begin their journey down to the soil to pupate. Once they burrow into the soil within the field, they will spend 10-14 days before emerging as adults. Any control tactics implemented before the populations shift toward their pupation stage will greatly reduce the next generation of adults.

 

• As mentioned last week, Squash bugs are actively laying eggs all over summer and winter squash leaves. Though numbers seem to be down significantly from last year, there are still quite a few egg masses being laid in the crops that we’ve been scouting. Be on the lookout for their copper eggs on the underside of leaves. Row cover can also be useful prior to flowering There are some limited chemical options available for organic growers, and similar to striped cucumber beetle, squash bugs also prefer the maxima variety of winter squash.

Thanks to all of the growers that have reached out with there own questions and pest scouting information. All information and questions help us to better serve the needs of the VVBGA community.

 

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	Most populations in the region are now a mix of large and small larvae.  But there are many 4th instar larvae ready to pupate
Flea Beetle	Most all brassica crops	We continue to see flea beetle. However, because most brassicas are larger in size, the relative pressure from flea beetles is low.
Imported cabbage worms Diamondback moth	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We are continuing to see larval feeding damage in many brassicas. Diamondback moth are also being found in brassicas in both adult and larval stages.
Leek moth	Garlic	The second flight of leek moth has begun! Adult moths are currentlty laying eggs in alliums
Mexican bean beetle	beans	Adults are being seen in significant numbers. Eggs and larvae are minimal at this point.
Potato Leafhoppers	beans and potatoes	Hopper burn is being found in beans and potatoes. It seems to be increasing in severity in many of the crops that we’ve scouted.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are becoming substantial and damage is significant, especially in cucumbers and C. maxima varieties of winter squash.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	Very few reports of leaf miner damage.
Squash bugs	Summer and Winter Squash	We’re seeing a plethora of adults and eggs with summer and winter squash. Nymphs are yet to be seen in any significant numbers
Squash vine borer	Winter squash	Moths are being found in traps from around the region. Moths are likely beginning to mate and lay eggs in squash plantings.
Tarnished plant bug	Strawberries	We are seeing a high incidence of tarnished plant bugs  in the region, especially in strawberries. Cat-facing and other types of strawberry deformation from the “sting” of the bug has been seen.

Hi all,

This week we are seeing exponential growth in several populations of common pests and some newly arriving pest & diseases that we should keep out eye out for in the coming weeks.

Basil Downy Mildew is being reported in the region, with confirmed occurrences in Western Mass and Rhode Island over the past week. BDM can severely affect basil plantings, and if left untended can lead to complete crop loss. The tell-tale sign of BDM is a gray coloring (from the developing spores) on the underside of basil leaves. It can sometimes look like soil has kicked up onto the bottom of the leaf.  If you suspect that it is BDM, you can place the affected leaves in a Ziploc bag with a wet paper towel to increase the sporulation. You can often be alerted to a potential outbreak by yellow coloring between the veins on the topside of leaves.

A great resource for identifying, reporting, and managing BDM is the Ag Pest Monitoring Site for basil. In recent years, some resistant cultivars have been developed. These cultivars and information on them may be found on the monitoring site too.  For those dealing with a current outbreak, prompt removal of affected plants will help to reduce the inoculum from infecting other plants. If you suspect that you are seeing BDM, please send us a message and/or send a sample to the Plant Diagnostic Clinic here at UVM.

Other important notes:

Thanks to the some of the recent larger storms in the regions, Fall Armyworm are being found in states just south of us (e.g. NY and CT.) Currently, numbers are low both in CT and NY, but it is likely that adult FAW moths will begin to move into our region soon.

Squash vine borer are being seen in traps being monitored in NH, CT, and MA. Though the current numbers being reported are low, as the next few weeks heat up, those numbers will certainly tick up.  The primary sign of SVB is the wilting of squash plants in the summer heat. With a closer inspection, you can find tunneling within the vines at the base of the plant. Unfortunately, once wilting is observed, there is very little that can be done to save the plant.  Exclusion netting can be useful for excluding moth from plantings, though this strategy is only useful prior to flowering and the need for pollinators. Well-timed applications, chemical and non-chemical (e.g. diatomaceous earth), near the base of plants during the early stages of flights can be useful. Traps with SVB lures can often provide growers with a good resource for timing controls for their specific farm.

Colorado potato beetle populations are exploding in potato plantings around the state. Here in Burlington we are seeing mix of small and large larvae within potato fields. This is prime time to apply any above-ground tactics to reduce the current population size. That window may close as the larger larvae begin to head down to the soil to pupate. Larger larvae tend to become pink or salmon colored just before they crawl down the plant to burrow into the soil to pupate. However, there is some evidence that entomopathogenic nematodes may be a useful tool (as a soil drench) for reducing the in-field populations during the pupation stage/process.

Squash bug adults and eggs are being found in increasing numbers throughout Vermont. Check on the underside of leaves for their meticulously placed golden brown eggs. Straw or hay mulch can exacerbate squash bug outbreaks, as they tend to provide the perfect habitat for the pest during the hot and dry times of the day. Row cover can also be useful prior to flowering. Like cucumber beetle, squash bugs tend to prefer maxima species of winter squash.

As always you can find more details on other pests and diseases at our pest and scouting website.

 

Cheers,

Vic

 

 

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	Most populations in the region are now a mix of large and small larvae.  Soon the larger larvae will begin their journey down the plant to pupate.
Flea Beetle	Most all brassica crops	We continue to see large populations of flea beetle. We are especially seeing sustained populations in cooler regions of the state in the Connecticut River Valley.
Imported cabbage worms Diamondback moth	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We are now seeing larvae feeding damage in many brassicas. Diamondback moth are also being found in brassicas in both adult and larval stages.
Leek moth	Garlic	We are still not seeing adult moths in traps yet, suggesting that the second and generally most damaging flight has yet to occur. We’re primarily seeing larval damage and pupae in the upper canopy of allium plantings.
Potato Leafhoppers	Alfalfa	We have official reports of PLH in beans within Vermont. They will likely persist and cause harm in other crops as the season progresses.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are becoming substantial and damage is significant, especially in cucumbers and C. maxima varieties of winter squash.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	Very few reports of leaf miner damage.
Squash bugs	Summer and Winter Squash	We’re seeing a plethora of adults and eggs with summer and winter squash. Nymphs are yet to be seen in any significant numbers
Squash vine borer	Winter squash	Moths are being found in traps from around the region. Moths are likely beginning to mate and lay eggs in squash plantings.
Tarnished plant bug	Strawberries	We are seeing a high incidence of tarnished plant bugs  in the region, especially in strawberries. Cat-facing and other types of strawberry deformation from the “sting” of the bug has been seen.

Hi all,

This week we are primarily seeing the transition of pest populations as they move into new life stages or begin to build toward

The most important of the new findings are reltated to potatoes:

• Potato Leafhoppers have been officially identified within Vermont. The two incidents are related to beans, though PLH does have an extensive host range including soybeans, potatoes, alfalfa, etc.
• Colorado potato beetles eggs have been hatching in all of the potato plantings that we’ve been monitoring. Most populations are in the early stages (1^st and 2^nd instars) of their larval development. With the warm and dry temperatures that we’ve been seeing, the impact of those little red larvae can be significant and will only increase in severity as the season progresses. Generally, the early larval stage is most susceptible to chemical controls.

Some other important notes:

Diamondback Moths and Imported Cabbage worms are being seen in various brassica crops. Larval numbers are minimal from our scouting but that may not be the case everywhere. Check on the underside of leaves and rib-lines of brassica leaves for the green camouflaged larvae. The adults of ICW are also known as “Cabbage Whites”, as they are day-flying white butterflies. Diamondback moths are small moths, one of the smallest moth pests of brassicas, that flutter up from the canopy when disturbed.  

Striped cucumber beetles are in full force in most squash and cucumber plantings. We are seeing lots of mating pairs and feeding damage, especially in winter squash of the maxima species (e.g. Blue Hubbard).  Though feeding damage can be worrisome for smaller plants and seedlings, SCB are also a vector of bacterial wilt which can be quite a challenge. Cucurbita maxima is known to be the preferred species of winter squash for cucumber beetles (and squash bugs) and is often utilized as a trap crop for other less preferred species (C. pepo and C. moschata). C. maxima has been well researched as a potential trap crop. Information the specifics of the trap-crop systems may be found here.

Thanks to all of the growers that have reached out with there own questions and pest scouting information. All information and questions help us to better serve the needs of the VVBGA community.

 

 

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	Most populations in the region are now in the early stages of larval development. This is both the most damaging stage for the crop, as the larvae can feed extensively and the most susceptible stage for the beetle to chemical controls.
Flea Beetle	Most all brassica crops	We continue to see large populations of flea beetle. We are especially seeing sustained populations in cooler regions of the state in the Connecticut River Valley.
Imported cabbage worms Diamondback moth	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We are now seeing larvae. Diamondback moth are also being found in brassicas in both adult and larval stages.
Leek moth	Garlic	Larvae are being found in modest numbers feeding on scapes in hard neck garlic and many of those larvae are currently transitioning to pupae. We expect that the next flight will be very soon.
Potato Leafhoppers	Alfalfa	We have official reports of PLH in beans within Vermont. They will likely persist and cause harm in other crops as the season progresses.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are becoming substantial and damage is significant, especially in cucumbers and C. maxima varieties of winter squash.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	We continue to see leaf mining, but eggs are few and far between. It looks like the most recent generation is mostly in the larval mining stage or pupating in the soil.
Tarnished plant bug	Strawberries	We are seeing a high incidence of tarnished plant bugs  in the region, especially in strawberries. Cat-facing and other types of strawberry deformation from the “sting” of the bug has been seen.

Hi all,

The past week of scouting and monitoring has revealed much of the same from the prior week. No new pests but increasing numbers and pressure from resident pests.

There have been several reports of fusarium in garlic. Fusarium can often be the result of a secondary infection from wounds being inflicted by other culprits such as mites or insects. So be on the lookout for signs of primary pests by checking any of the infected plants for potential initial sources of damage.  This may give you some important information for managing the problem going forward.

Speaking of alliums, as garlic scapes are beginning to emerge in hardneck garlic, leek moth larvae are being found in modest numbers feeding upon or near those aromatic scapes. Leek moth larvae are known to preferentially feed upon garlic scapes and since populations are in the larval stage for most of the region, it is no surprise that we are seeing scape damage. If you value your scapes, it might be advisable to harvest them sooner than later.  We anticipate that with warmer temperatures on the horizon, we’ll see extensive feeding and a fast transition from larvae to pupae in the next couple of weeks.

Some other important notes:

Cucumber beetle populations continue to build in the Vermont, especially in the warmer areas in southern VT and close to Lake Champlain.  As mentioned last week, weed management and row cover can be effective strategies for reducing the impact on vulnerable transplants.

Colorado potato beetles are being seen in increasing numbers, but at our two monitoring sites we’re still only seeing adults and eggs. We presume that some of those eggs will soon be hatching and unleashing those voracious larvae. So be sure to be checking under leaves to see if eggs are beginning to hatch. The larval stage of the beetle is both the most damaging and susceptible stage of the beetle, especially for chemical control.  

Spinach leaf miner damage is also being reported in much of the region. Damage can be quite severe in beets and chard. Once the larvae find their way into the leaf, control options can be limited.  The characteristic small white eggs can be easily seen on the underside of leaves.  There is some anecdotal evidence that the eggs are permeable to some chemical controls, but that remains untested. Preventive sprays before the eggs hatch can be useful if timed correctly. For organic growers, it is recommended to use spinosad based products (i.e. Entrust) with an added spreader-sticker to increase the potential of contact or feeding from larvae after hatching.

Finally, thank you to farmers that reached out regarding potential potato leafhopper sitings. As of now, we do not have a validated occurrence of PLH in Vermont. If you do think you are seeing PLH, please send along any pics or information you may have to Scott or me. We are in the process of setting up a submission form on our website for sharing details or questions like these, but in the meantime, just send any pest questions directly to our email addresses slewins@uvm.edu or vizzo@uvm.edu

 

 

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	Still are not seeing any larvae but they are soon to be hatching. Be vigilant if you are planning any control measures.
Flea Beetle	Most all brassica crops	We continue to see large populations of flea beetle. We are especially seeing sustained populations in cooler regions of the state in the Connecticut River Valley.
Imported cabbage worms	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We still have not seen larvae yet, but that should only be a matter of time.
Leek moth	Garlic	Larvae are being found in modest numbers feeding on scapes in hard neck garlic.
Potato Leafhoppers	Alfalfa	Reports of hoppers from NY growers indicate that hopper are being found in alfalfa. Maine has reported PLH in some crops too. We are yet to see them or hear about them in VT.  Be on the lookout.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are building in the field but the damage is not yet causing too much damage.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	We continue to see and hear of leaf mining and eggs from various Vermont farmers.
Tarnished plant bug	Strawberries	We are seeing a high incidence of tarnished plant bugs  in the region, especially in strawberries. Cat-facing and other types of strawberry deformation from the “sting” of the bug has been seen.

Hi all,

As we begin the slow roll into June, it is peak season for the emergence and arrival of many of our most concerning insect pests. Unfortunately, it seems that the early season rains combined with warming drier temperatures, has led to some early outbreaks and arrivals.

One  of the more important scouting notes this week is the arrival of potato leafhopper (PLH) populations within the northeast farming region. We have received warnings from both Maine and New York extension folks that PLHs are being seen in alfalfa and potentially other crops. PLH can be a serious pest in a variety of crops including potato, beans, eggplant, alfalfa, strawberries, among many others. Legumes tend to be their preferred host.

We have not witnessed any hoppers or the characteristic “hopper burn” symptoms in any of the crops that we are monitoring, and we have yet to hear any reports of PLH from VT farmers. Though, it is only a matter of time before we see or hear about them in Vermont.  So, it is a good time to start scouting for the adults and small green nymphs. Tapping or brushing the plants is one way to check plants for adults (they’ll jump/fly when disturbed) but you’ll need to look on the underside of leaves to find the wingless nymphs. The sooner you are able to identify them the better, as once you get “burned” the damage is not reversible.

Luckily, PLHs are not able to overwinter this far north. However, once they are found in the region, they are here to stay for the season.  PLH populations often exhibit explosive population dynamics, with rapidly growing populations soon after colonizing a crop, so be on the lookout and let us know if you see anything!

A few other important notes from the past week:

As mentioned last week, Colorado potato beetle adults are actively laying eggs in eggplant and potato plantings. We’ve even seen some colonizing field tomatoes. In the next week or so, those eggs are will start to hatch, if they haven’t already. The larval stage of the beetle is the most damaging stage, so any control tactics should be timed accordingly.

We’re seeing a lot of slug pressure in lower lying wetter areas. Slugs are particularly an issue in crops that capture and hold water within their foliage (e.g. napa cabbage, lettuces, etc.), though they can just about eat any broadleaf crop. Commercially available baits containing iron phosphate, are shown to be rather effective and with a low impact on the environment.

Striped cucumber beetle are also actively colonizing squash plantings in the area. More and more growers are using floating row covers as an early season control strategy. Once plants are large enough and flowering, the row cover can be removed for pollination. Cucumber beetle are also vectors for bacterial wilt, so any efforts to reduce their populations or feeding early in the season is beneficial for the long-term health of the crop. Because they feed on a various weeds (e.g. wild amaranth, lambsquarters, etc.), it is important to be cognizant of the weed species in and around fields and manage accordingly.

 

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	High numbers of CPB in eggplant and potato. Adults are mating and laying eggs at a precipitous rate. Eggs will be hatching soon if they haven’t already.
Spinach/Beet leaf miner	Spinach, Swiss Chard, Beets	Adult flies are flying and laying eggs. Many reports of leaf mining and eggs from various Vermont farmers.
Striped Cucumber Beetle	Squash/Cucumber	Beetles are being seen and reported in numerous cucurbit crops. Numbers are building in the field.
Flea Beetle	Broccoli/ Kale	We are in peak flea beetle season. Large populations are being reported throughout the state are continuing to be feeding and causing significant damage.
Imported cabbage worms	Brassica crops (Kale, Broccoli, Cabbage, etc.)	Cabbage whites are flying and laying eggs. We have not seen larvae yet, but that should only be a matter of time.
Tarnished plant bug	Strawberries	Tarnished plant bugs are being found in strawberries in the region. Cat-facing and other types of strawberry deformation from the “sting” of the bug has been seen.
Potato Leafhoppers	Alfalfa	Reports of hoppers from NY growers indicate that hopper are being found in alfalfa. Maine has reported PLH in some crops too. They are likely here in VT, so be on the lookout.

Hi all,

This week we have officially added a new monitoring site outside of Chittenden County. The farm team at Cedar Circle Farm in Thetford, VT will be sharing their weekly observations and scouting reports with our team to better capture the distribution and movement of pests throughout the region.  We’ll incorporate their data to our weekly reports to give a more complete picture of the pest and disease issues in the state.

In general, we are starting to see things really picking up over the past week. With the consistent rains and new plantings out in many fields and gardens, pests are arriving in droves.

Some highlights from the past week at our locations are:

Colorado potato beetle adults are being found in large numbers mating and laying eggs in eggplant and early season potatoes. Be sure to check under leaves for the characteristic orange egg masses. In the next couple of weeks expect those hungry larvae to begin emerging from their eggs. Larvae are the most damaging stage of the beetle, but are also most susceptible to chemical treatments. Also, in recent years many farmers have reported success in reducing CPB damage by delaying planting.

Flea beetle infestations are being reported by many growers and gardeners. Floating row covers or insect exclusion netting for seedlings and smaller plants can be a very effective strategy for minimizing the impact of flea beetles on brassicas until plants are large enough to tolerate the pressure.

Cabbage white butterflies, the adult form of the imported cabbageworm, are actively flying in the region and laying egg on brassicas. We are yet to see larvae or their characteristic leaf feeding damage. Larvae and eggs can be found on the underside of leaves. Smaller larvae can be difficult to see, as they are green and camouflaged.

Spinach leaf miner eggs and larval tunnels have been reported by growers in NY, though we are yet to see them on plantings in Burlington. They are likely flying and laying eggs here in Vermont, however, the susceptible plants (e.g. spinach, chard, etc.) at the UVM farm are still under row cover for protection so we haven’t seen them. Their bright white eggs are easily identified on the underside of leaves, in collections of 2-10 eggs. Spinach leaf miner infestations can often be exacerbated by the presence of lamb’s quarters and wild amaranth species. So, weed management can have a significant effect on their impact.

And finally, as mentioned last week, Striped cucumber beetle are being found in high tunnels and are showing up in some field plantings of cucurbits.

As always you can find our weekly reports at go.uvm.edu/pests

Feel free to reach out to us if you have any questions.

vizzo@uvm.edu & slewins@uvm.edu

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	High numbers of CPB in eggplant and potato. Adults are mating and laying eggs at a precipitous rate.
Spinach leaf miner	Spinach, Swiss Chard, Beets	Adult flies are flying and laying eggs. Some larval tunneling is being reported in NY and a few growers in Vermont.
Striped Cucumber Beetle	Squash/Cucumber	Several farmers have reported the arrival of cucumber beetles in high tunnels. Numbers are low in any field cucurbits at the current time.
Flea Beetle	Broccoli/ Kale	We are in peak flea beetle season. Large populations are being reported throughout the state.

Hi all,

With all of the heat and rain over the past week, several of our early season pests have begun to emerge and are being found in relative abundance in fields and high tunnels in the region.

As mentioned last week, we are particularly interested in keeping an eye out for signs of the allium leaf miner, (ALM), as we would like to monitor the expansion of this new invasive pest. The adult female fly deposits eggs directly in the leaves of allium plants leaving a distinct line of white dots (egg laying scars).  ALM’s impact is seen during the early spring and can be a significant issue for growers harvesting scallions or overwintered onions. The ALM displays a summer hibernation which typically begins around the first week of June and ends around September. So it typically is not an issue for garlic and onion growers. However, the second generation emerges just in time to affect any late season alliums (e.g. leeks). 

A few other highlights from the last week:

Colorado potato beetle: Reports of emerging adult beetles are being shared throughout the region. Adult beetles will seek out both wild and cultivated solanums during this time of the season. This overwintering generation will begin mating and laying eggs over the next week, so be sure to scout under the leaves of any solanum crops (e.g. tomatoes, eggplants, etc.) that you may have out there in your fields. 

Flea beetles: Flea beetles seem to be thriving, as we’ve seen some large outbreaks in brassica plantings. Row covers for small seedlings can be an effective strategy for dampening their impact on the sensitive plants. 

Cabbage root maggot: According to the degree day models from NEWA, overwintering populations of cabbage maggot flies are roughly ~95% emerged from their overwintering habitat. Adult females are actively laying eggs at the base of brassica crops. 

Striped cucumber beetle: Beetles have arrived on some farms, especially in unscreened high tunnels. We anticipate that these populations will be growing at a rapid rate over the next few weeks. 

Our new website for the scouting reports can be found here

For detailed management information about these pests, as well as a comprehensive guide to current  production and pest management techniques for commercial vegetable crops, check out the new and improved New England Vegetable Management Guide. And, as always feel free to reach out to us if you have any questions.

vizzo@uvm.edu & slewins@uvm.edu

Pest	Crop	Observations
Colorado Potato Beetle	Potatoes	CPB adults are currently emerging from their overwintering habitat,  these adults are searching out their first host plants to mate and lay eggs.
Leek Moth	Onions/Garlic	Adult moths from the emerging overwintering population are no longer showing up in baited traps. Eggs are likely developing on alliums, however, we are yet to  see any larvae or feeding damage in any alliums.
Striped Cucumber Beetle	Squash/Cucumber	Several farmers have reported the arrival of cucumber beetles in high tunnels
Flea Beetle	Broccoli/ Kale	Beetles are being found in high numbers in many brassica crops. Row covers can be an effective strategy for protecting vulnerable brassica seedlings.