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Vegetable Notes 2026 Vol. 38:21

August 27, 2026
In This Issue
  • Crop Conditions
  • Pest Alerts
  • Group 22 Herbicides
  • Identifying Potato Tuber Diseases
  • News
  • Events
  • Sponsors

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Click on images to enlarge.

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Crop Conditions

strawberry plants growing in a high tunnel
Extension berry specialists from around New England gathered at Nourse Farm this week to learn more about their plant production facilities and discuss current berry challenges and opportunities for research and collaboration. Photo: S. B. Scheufele

It’s suddenly feeling like fall, with cool, dewy mornings and slightly lower temperatures during the day. Early potatoes are being harvested, winter squash is sizing up, fall root crops are steadily growing, and it’s almost time to start seeding winter greens. There is cured garlic to sort, and storage onions will be harvested soon. But it is still August, and tomatoes, eggplant, peppers, zucchini, summer squash, cucumbers, and sweet corn are also still coming in in full force. As we look towards fall and winter, we want to put it on your radar that registration for the 2026 New England Vegetable & Fruit Conference in Manchester, NH is now open. This is a 3-day conference with more than 140 presentations by researchers, Extension educators, and growers and 12 farmer-to-farmer discussions on fruit and vegetable production topics. There are sessions on all major fruit and vegetable crops, as well as sessions on farm business management, soil water management, cover cropping and reduced tillage, seed saving, and more. The full schedule is coming soon but registration is open now; visit the conference website HERE for more information and to register.

Contact Us

Contact the UMass Extension Vegetable Program with your farm-related questions, any time of the year. We always do our best to respond to all inquiries.

Vegetable Program: 413-577-3976, umassveg[at]umass[dot]edu (umassveg[at]umass[dot]edu)

Staff Directory: https://ag.umass.edu/vegetable/faculty-staff

Home Gardeners: Please contact the UMass GreenInfo Help Line at greeninfo[at]umext[dot]umass[dot]edu (greeninfo[at]umext[dot]umass[dot]edu).


Pest Alerts

Cucurbits

leaf spots on cantaloupe leaf
Alternaria leaf spot on cantaloupe. Photo G. Holmes, Cal Poly San Luis Obispo, Bugwood.org
Anthracnose lesions on leaf
Shot-hole appearance of anthracnose on cucurbit leaf. Photo R. L. Wick.

Anthracnose and Alternaria leaf spot were diagnosed on cucumber this week. These diseases may have been present in older successions and hopped over into a new planting where they are taking out foliage quickly. Both of these pathogens are fungi that overwinter in crop residue and then spread in-season via splashing water and people and equipment moving through crops. Anthracnose is commonly seedborne also. Many of the fungicides that you may already be applying for powdery and/or downy mildew will also control anthracnose, Alternaria, and other fungal diseases. Protectant fungicides like Bravo, copper, sulfur, and oils and some powdery mildew-targeted fungicides (e.g. Inspire Super, Proline, Procure, Luna Flex, Merivon Xemium) are effective against other fungal diseases. Other powdery mildew-targeted materials (e.g. Gatten) are only effective against powdery mildew. For a full list of materials labeled for anthracnose and Alternaria in cucumber, see the cucumber disease control section of the New England Vegetable Management Guide.

A close up of a cucumber leaf with angular yellow lesions.
CDM on upper side of cucurbit leaf.

Cucurbit downy mildew (CDM): Targeted sprays for all cucurbits are recommended now. CDM was reported recently on watermelon in Ohio; the pathogen clade that preferentially infects watermelons also infects winter squash and pumpkins. CDM was also reported on cucumber in Pennsylvania and Ohio—this clade also infects cantaloupe and tends to arrive earlier in the Northeast. With small storms coming up from the southwest, spores from these areas could soon arrive in Massachusetts. Growers should already be regularly applying preventative materials (chlorothalonil or copper) as part of their powdery mildew spray program and should now add CDM-targeted materials, rotating between at least 2 from different FRAC Groups. Recommended CDM-targeted materials are: Elumin (FRAC Group 22), Omega (Group 29), Orondis Opti (Group 29 + M05), Previcur Flex (Group 28), Ranman (Group 21), and Zampro (Group 40 + 45). More information about each material, including REIs and PHIs, can be found here.

Nightshades

Common scab of potato was diagnosed this week. See the article in this issue for help identifying tuber diseases as you harvest and cure the crop.

Herbicide injury was diagnosed on tomato this week. Upper leaves and stems of tomato plants appeared twisted, thin, and strappy. Several different varieties of tomato were affected similarly, and symptoms occurred abruptly. Tests for common tomato viruses that can cause similar leaf distortion were negative. In this case, it turned out that a neighboring corn field had been sprayed with dicamba and the tomato crop was injured by drift or vaporization. 

Dicamba is a synthetic auxin, or “growth regulator”, herbicide that has been used to control broadleaf weeds for over 50 years. It is regularly applied in corn, dicamba-resistant soybeans, and cotton, for right-of-way applications and in the early fall for control of perennial weeds. Dicamba can injure sensitive broadleaf plants if the tank is not thoroughly rinsed after spraying dicamba, and/or through particle drift during the dicamba application or vaporization after dicamba has been applied. Particle drift refers to the herbicide being carried off-target by the wind during the application. Wind speed, particle droplet size, nozzle type, carrier volume, application method, and application speed will affect the extent of particle drift. Vaporization, on the other hand, occurs when the herbicide evaporates from the target plant and these vapors travel off-target.  Low-volatile formulations of dicamba such as Clarity, Engenia, and Xtendimax with Vapor Grip Technology are intended to reduce volatilization compared to the original dimethylamine salt used in Banvel, but they do not eliminate volatilization completely.

Dicamba injury can cause plant death in extreme cases, or yield reduction in more moderate cases. Potential for yield loss is influenced by amount of dicamba as well as the point in the injured crop’s life cycle that the injury occurs. Tomatoes, peppers, eggplants, and legumes are among the most sensitive vegetable crops, but other broadleaf crops may also be affected. For more information see this Rutgers factsheet.

Sweet corn

Corn earworm (CEW) trap counts are once again variable across the state but warrant a 4-day spray interval in most locations. 

Fall armyworm (FAW): We are continuing to hear reports of FAW damage as moth numbers increase in some areas. Continue to scout whorl-stage corn and treat at a threshold of 15% of plants infested. 

Northern corn leaf blight: We’ve received more reports of damage on sweet corn from throughout the state. Damage that appears extensive now can be treated with fungicides; see the sweet corn disease section of the New England Vegetable Management Guide. The fungus overwinters in crop residue on the soil surface and will often continue to cause issues in successive years. Tilling in corn residue and rotating away from corn can help interrupt the fungal life cycle. Resistant varieties planted in later successions can also withstand higher disease pressure. 

Table 2. Sweet corn trap captures and growing degree days for week ending August 26
GDDs (base 50°F*)Trap LocationECB NY (2)ECB IA (1)ECB HybridFAWCEWCEW Spray Interval

Western MA

2178Northampton

-

-

-

-

-

N/A
2322Whately

0

0

0

14

2

6 days
2092Southwick

0

0

-

5

25

4 days
Feeding Hills

0

0

-

3

18

4 days
2234Granby

0

0

-

4

21

4 days

Central MA

2237Leominster

2

0

0

1

42

4 days
2207North Grafton

1

0

-

12

10

4 days
2099Spencer

0

0

-

5

3

6 days
2204Bolton

0

0

-

1

19.5

4 days

-

Townsend

0

0

-

2

11

4 days

Eastern MA

2280Concord

0

0

-

0

30

4 days
2243Haverhill

0

0

-

12

72

4 days
2160Ipswich

0

0

-

3

31

4 days
2307Littleton

-

-

-

-

-

N/A

-

Millis

7

2

-

-

66

4 days
2281North Easton

0

0

0

0

-

N/A
Sharon

0

0

0

-

70

4 days

-

Sherborn

0

0

-

6

30

4 days
2456Seekonk

0

0

0

1

105

3 days
Swansea

0

0

0

1

51

4 days

Group 22 Herbicides

Earlier this month, we shared an article all about Group 1 herbicides. Another group of herbicides worth highlighting are the bipyridinium compounds, which the Herbicide Resistance Action Committee has classified as Group 22 herbicides. There are 2 molecules within this group that are currently used as herbicides: paraquat and diquat. Diquat is commonly sold as the trade name Reglone and paraquat as Gramoxone, though there are other trade names with these active ingredients—see Table 32 in the New England Vegetable Management Guide for other products.

Diquat, usually formulated as diquat dibromide, is labeled as an herbicide in asparagus and as a crop desiccant in potatoes. Paraquat, usually formulated as a dichloride salt, is labeled for use as an herbicide in most vegetable crops and as a desiccant in dry beans and peas1,2. Both of these products are post-emergent, meaning they work on plants that have emerged from the soil, which is similar to the Group 1 herbicides. However, the similarity stops there. Group 22 herbicides are non-selective, meaning they work on all plants, unlike the Group 1 herbicides, which act almost exclusively on grasses. Additionally, Group 22 herbicides are contact herbicides, meaning that they only act on the part of the plant they touch, with essentially no transport through the plant vascular system. Again, this is different from the Group 1 herbicides, which travel through the phloem to areas of active growth.

Table 1. Bipyridinium herbicides labeled for vegetable crops in MA.

Active ingredient

Trade name (example)

Crops labeled

DiquatRegloneAsparagus, potatoes
ParaquatGramoxoneAsparagus, beans, brassicas, carrot, corn, cucurbits, eggplant, garlic, globe artichoke, lettuce, okra, onions, parsnip, peas, peppers, potatoes, pumpkins, rhubarb, rutabaga, sweet potato, tomato, turnip

How Group 22 Herbicides Work

I like to think about the mode of action of these products as similar to a transformer blowing up. Before paraquat was formulated as an herbicide, it was regularly used in biochemistry laboratories as a oxidation-reduction indicator, because it is a potent reducing agent, meaning it strongly accepts electrons2,3. In other words, it is basically a really strong chemical magnet. When applied as an herbicide, it enters the chloroplast of plant cells and attracts an electron from photosystem I. Photosystems I and II are groups of proteins in plant chloroplasts that basically conduct photosynthesis; the photosystems receive light from the sun and use it to create molecules within the cell that store energy which can then be released for use in the cell. Very simply put, in the process of photosynthesis, an electron is knocked off of photosystem II and passed along a chain of different molecules until it reaches it's final home. When paraquat attracts an electron from photosystem I, it disrupts this process.

That first electron diversion is like the arc of electricity in a transformer explosion. From there, this diverted electron goes in all the wrong places. I'll describe the fallout here, but the basics are that the diverted electron bounces around chaotically until the whole cell blows. The diverted electron creates a reduced cation radical, which then reacts with oxygen to create super oxide, which is an unstable, negatively charged oxygen molecule. Super oxide is common in very small quantities in most aerobic organisms, so there are molecules present in cells that routinely turn superoxide back into oxygen and peroxide. So, the presence of small quantities of super oxide isn’t a problem, but when paraquat is applied, there is too much peroxide. It begins to react with excess superoxide and positively charged iron ions, also from photosystem I, and creates hydroxyl radicals. These hydroxyl radicals react with larger molecules within the cell, such as cell membrane lipids, DNA, proteins, and carbohydrates, which disrupts their functions, ruptures the membranes, breaks open the cell, and then leaks water and kills the tissue4,5.

Group 22 Herbicide Characteristics

Hopefully a better understanding of how Group 22 products work will help you make more effective and safer applications. Some important characteristics of these materials are:

They are non-selective

Since the site of action of Group 22 herbicides is the chloroplast and the mode of action is brute force, these products are non-selective and work on all plants. There are only a few other non-selective herbicides: glyphosate and glufosinate (which, despite both being non-selective and having similar names, are actually very different products that work in very different ways). When applying non-selective herbicides, you typically need to protect the crop from the herbicide spray with a hooded or shielded sprayer, or crop injury or death may occur. However, just because Group 22 herbicides work similarly on all plants, it does not mean they kill all plants successfully. 

They are contact herbicides

plants showing herbicide damage
Figure 1. Paraquat is a contact herbicide – you can practically see where the drops of herbicide have hit the plant and destroyed the cells. Good coverage is essential for effective weed control. Photo M. Gannett

Group 22 herbicides are only effective on plant cells that they come into contact with. They essentially do not travel through the plant (Fig. 1). This has several consequences:

  • They do not affect roots of plants, so perennials can easily re-sprout. These products will “burn down” green tissue but will not kill established perennials or plants with thick bark.
  • You need to ensure good coverage of the plants you’re trying to control, otherwise they won’t be affected by these herbicides.
  • These products are fast-acting. Since they don’t need to move anywhere within the plant to have effect, you will see symptoms of herbicide injury within a few hours of application.

Cloudy weather can slow activity

These products need both oxygen and sunlight to work. They’re stealing electrons from photosystem I during photosynthesis, so if there’s no sunlight to start the process of photosynthesis, there will be no electron for them to steal and you will not see damage. Typically, this isn’t a problem, but you will notice on labels that cool, cloudy weather can slow activity.

Short plant-back intervals

These products adsorb very strongly to soil particles, which essentially makes them inert once they’ve touched soil6. This is helpful because it means you can plant a crop soon after the application of a Group 22 herbicide. Paraquat is frequently recommended for practices like stale seedbedding because you can “burn down” all germinated weeds and then quickly replant without any risk of residual herbicide harming the crop.

Safety of Group 22 Herbicides

The biggest concern about using Group 22 herbicides, especially paraquat, is safety for humans and animals. 

Paraquat is a strong electron acceptor and it will also pull electrons from cells of other aerobic organisms. Of all the herbicides labeled for use in fruit and vegetable crops, it has the lowest oral LD50, which is a measure of how much product was needed to kill 50% of a population of rats when eaten. A small LD50 is more dangerous, because this indicates that even just a small amount can kill something. Additionally, the mortality rate is high, meaning that the likelihood of death after ingestion is high7. There’s just not a lot that can be done to stop it from acting once it’s inside the body. If we think about that transformer, it’s hard to stop an explosion once that first arc is made, so the most important thing to prevent explosions is to make sure the arc never happens.

The paraquat label has a lot of requirements to try to prevent exposure and keep people safe. Here are a few key requirements, but be sure to thoroughly read and follow the label before applying:

  • NEVER transfer paraquat into a different container. If it’s not in its official container, someone could mistake it for something else and accidentally ingest it.
  • Wear the appropriate respirator when handling, mixing, loading, or applying paraquat (NIOSH-approved particulate filtering facepiece respirator with any R or P filter; OR a NIOSH-approved elastomeric particulate respirator with any R or P filter; OR a NIOSH-approved powered air purifying respirator with HE filters).
  • If applying to more than 80 acres within 24 hours, apply in a completely enclosed cab.
  • Mixers and loaders must also wear a chemical-resistant apron and a face shield.
  • Paraquat can only be removed from its original container if it’s smaller than 120 gallons with a closed transfer system (Fig. 2). You can read more about those in this Sprayers 101 article. Sprayers 101 is a Canadian nonprofit focusing on practices to ensure safe agricultural spraying. Some of the Canadian regulations are different, but the information is great.
  • The Re-Entry Interval (REI) was relatively recently increased to 48 hours if used as an herbicide, and 7 days if used as a desiccant, so be sure everyone is aware not to enter treated areas in this timeframe.
  • Paraquat is a restricted-use pesticide, so only licensed applicators can apply this product.
  • On top of the Massachusetts pesticide application requirements, there is an additional paraquat-specific safety training that must be completed every 3 years to use the product. This training goes into further detail on how to keep yourself and others safe. https://www.epa.gov/pesticide-worker-safety/paraquat-dichloride-training-certifiedapplicators
table showing images of different herbicide application tools
Figure 2. Comparison of 3 commercially available closed transfer systems to improve the safety of mixing and loading paraquat8.

Recently, there have been increasing calls to re-evaluate paraquat use. Earlier this summer the EPA announced that they plan to host a paraquat roundtable to “convene scientists, experts, and advocates to examine safety questions, solutions, and alternatives”. It has not yet been scheduled but we will share details about this event when they are announced. More recently, the California Department of Environmental Protection (DPR) announced a voluntary cancellation of all paraquat products, meaning that all companies that manufacture and sell paraquat have decided to remove their registration for CA, but these products are still registered for use by licensed applicators in MA, so we hope this information will help you use them as effectively and safely as possible.

Works Cited:

  1. Homepage : New England Vegetable Management Guide : UMass Amherst. https://nevegetable.org/.
  2. Bromilow, R. H. Paraquat and sustainable agriculture. Pest Manag. Sci. 60, 340–349 (2004).
  3. Michaelis, L. & Hill, E. S. THE VIOLOGEN INDICATORS. J. Gen. Physiol. 16, 859–873 (1933).
  4. Hawkes, T. R. Mechanisms of resistance to paraquat in plants. Pest Manag. Sci. 70, 1316–1323 (2014).
  5. Dodge, A. D. & Harris, N. The mode of action of paraquat and diquat. Biochem. J. 118, 43P-44P (1970).
  6. Roberts, T. R., Dyson, J. S. & Lane, M. C. G. Deactivation of the Biological Activity of Paraquat in the Soil Environment: a Review of Long-Term Environmental Fate. J. Agric. Food Chem. 50, 3623–3631 (2002).
  7. Chen, C.-K. et al. The acute paraquat poisoning mortality (APPM) score to predict the risk of death in paraquat-poisoned patients. Clin. Toxicol. 60, 446–450 (2022).
  8.  Sasturain, J. et al. Minimizing operator exposure: field data analysis of three closed transfer systems for pesticide mixing and loading. J. Consum. Prot. Food Saf. 19, 143–153 (2024).

--Written by Maria Gannett, UMass Extension Weeds Specialist


Identifying Potato Tuber Diseases

There are many diseases that affect potato tubers, so ahead of your potato harvest this year, take a moment to familiarize yourself with the range of symptoms. Proper identification will help you decide which tubers will store well and which should be sold as tablestock, and will give you a better idea of which soil-borne diseases are present in your fields, improving your future crop rotations. To be sure of a diagnosis, samples can be submitted to the UMass Plant Diagnostic Lab. Most of these diseases (except for scabs, scurfs, and potato virus Y) get started on foliage and, if controlled there, can be prevented on tubers. See the potato disease control section of the New England Vegetable Management Guide for fungicide recommendations. 

Common scab (Bacterial: Streptomyces spp.)

Patchy lesions covering potato tubers.

Common scab produces tan to dark brown, circular or irregular lesions, which are rough in texture. Scab may be superficial (russet scab), slightly raised (erumpent scab), or sunken (pitted scab). The type of lesion is dependent on potato cultivar, tuber maturity at infection, organic matter content of soil, strain of the pathogen, and the environment. Common scab is controlled or greatly suppressed at soil pH levels of 5.2 or lower, though a closely related but less common species of Streptomyces known as acid scab can survive down to 4.0. 

Maintaining moist soil conditions, especially during tuber initiation, can be an effective way to prevent scab infections, though is usually tricky to implement on the scale most potatoes are grown. 

Some varieties are more susceptible to scab than others, with red-skinned varieties generally being most sensitive and russets being most resistant. From Christopher Clark, USDA-ARS Vegetable Breeder, “Some recently released cultivars that are at least partially common scab resistant are Lamoka, Upstate Abundance, and Caribou, though none of these are highly scab resistant. In our very limited trials, Blazer, Canela, and Gold Rush Russet potatoes performed better for common scab resistance than some of the more commonly grown russets when challenged with the species of the pathogen that appears to be the most prevalent in New England. For red potatoes, Dark Red Norland performed the best for scab resistance in some of our limited trials among red potatoes, though it is still quite susceptible. Superior is a white potato that performs reasonably well for scab resistance.” 
For conventional growers, the fungicide quintozene (Blocker) seems to work quite well. 

Early blight (Fungal: Alternaria solani) 

Dark lesions on potato tuber

Early blight usually affects potato foliage but tuber infections can also occur. Tuber lesions are dark, sunken, and circular, and are often bordered by raised, purple to gray tissue. The underlying flesh is dry, leathery, and brown. Lesions can increase in size during storage, causing tubers to become shriveled.

Fusarium dry rot (Fungal: Fusarium spp.)

Dark brown dry rot on interior of potato tuber.

Fusarium dry rot causes internal, light to dark brown or black dry rot of the potato tuber. The rot may develop at an injury site, such as a bruise or cut. The pathogen penetrates the tuber, often rotting out the center. Extensive rotting causes the tissue to shrink and collapse, usually leaving a dark sunken area on the outside of the tuber and internal cavities.

Silver scurf (Fungal: Helminthosporium solani) 

Pale brown lesions on skin of potato tuber

Silver scurf affects only tuber periderm (skin). Lesions start at the stolon end of the tuber as small, pale brown spots which may be difficult to detect at harvest but will continue to develop in storage. In storage, lesions may darken and the skin may slough off. Many small circular lesions may coalesce to form large affected areas. Tubers may also dry out and become wrinkled due to excessive moisture loss in storage.

Black dot (Fungal: Colletotrichum coccodes)

Large brown patch of discoloration covering roughly half of a potato tuberClose-up of black sclerotia on surface of potato tuber

On potato foliage, symptoms of black dot are nearly indistinguishable from early blight. On tubers, it produces large discolored areas that can easily be mistaken for silver scurf. Under a 10X lens, tiny black sclerotia are visible on the surface of the affected tissue. 

Black scurf and Rhizoctonia canker (Fungal: Rhizoctonia solani)

Large sunken lesions across exterior of potato tuber. Potato tuber covered in black spots

Black scurf is purely cosmetic and does not reduce yield, even in storage. Irregular, hard, black masses that develop on tuber surfaces are overwintering structures (sclerotia) of the fungus. Development of these sclerotia may be minimized by harvesting tubers soon after vine-kill and skin set. While the sclerotia themselves do not cause damage, they allow the pathogen to survive in the soil and serve as evidence of its presence. In cool, wet soils, R. solani can cause dark, sunken lesions on underground sprouts and stolons. These lesions can cut off the supply of nutrients and kill tubers, or can reduce the transfer of starches to the tubers, reducing their size. Cankers can also form on the tubers themselves, usually at the stolon or in lenticels. Tuber cankers vary greatly in size, from small and superficial to large, sunken, and necrotic.

Pink rot (Oomycete: Phytophthora erythroseptica)

Cross sections of potato tubers showing pink and black infected tissue

Pink rot infections start at the stolon end of tubers and result in rotten and discolored periderm with a clear delineation between healthy and diseased tissue. When exposed to air, tuber flesh turns pink and then brown-black. 

Pythium leak (Oomycete: Pythium spp.)

Watery brown rot throughout the interior of a tuber.

The Pythium species that cause leak infections invade tubers through harvest wounds and continue to develop in transit and storage. Infections result in internal watery, gray or brown rot with well-defined red-brown lines delineating healthy and diseased tissue.

Late blight (Oomycete: Phytophthora infestans) 

Dark-colored spots on exterior of tubers.

Late blight affects potato foliage and tubers. Foliar symptoms start with brown to black, water-soaked lesions on leaves and stems, which produce visible white sporulation at the lesion margins under humid conditions. Whole plants and fields may collapse rapidly. Tuber infection is initiated by sporangia from foliage being washed down into the soil and usually begins in wounds, eyes, or lenticels. Lesions are copper brown, red or purplish and white sporulation may occur on tuber surfaces in storage or cull piles. Infected tubers are susceptible to infection by soft rot bacteria, which can turn entire bins of potatoes in storage into a smelly, rotten mass. (We haven’t had any reports of late blight in Massachusetts in 2026, and so far there has only been one report 2 weeks ago in North Carolina.)

Potato virus Y (PVY) 

Rotting patches on surface of potato tubers surrounded by distinct brownish rings

PVY can cause necrotic ringspots on tubers, depending on which strain of the virus is present, which potato variety is grown, and the time of infection. Affected tubers have roughened rings of darker brown or reddened skin. Necrosis beneath the rings may extend into the tuber flesh. Necrotic symptoms in tubers often increase after storage. Potato varieties vary in their susceptibility to PVY and the symptoms they exhibit on foliage and on tubers; Yukon Gold is particularly susceptible to tuber necrosis. Management of this disease starts with sourcing certified disease-free seed tubers, then preventing spread by aphids by planting buffers around the potato crop.

Physiological Disorders

Black heart

Cross section of potato tuber with blackened area at its core

Black heart is caused by lack of oxygen during storage, which causes the tissue to die from the inside out and turn black. The condition is not reversible, but if you notice it quickly and correct your storage conditions you can prevent the whole crop from being affected.

Brown center and hollow heart 

Cross section of potato tuber with the core rotted and hollowed out

Brown center and hollow heart are internal physiological disorders of potato that often occur together. Brown center is an area of dead pith cells that turn brown, while hollow heart is a star- or lens-shaped hollow area in the center of the tuber. These disorders make fresh-market tubers unattractive and can reduce repeat sales. Severe hollow heart negatively impacts the quality of chip-processing potatoes and can result in shipments not making grade. Both disorders are related to stress, and occur at a higher incidence when growing conditions abruptly change during the season. Brown center and hollow heart likely form during tuber initiation but could also form during tuber bulking. If the disorder occurs during the early part of the season, it most often begins as brown center that forms in the stem-end of the tuber, while late-forming hollow heart usually occurs near the bud-end with no brown center symptoms. Conditions such as soil temperatures below 56°F for 5-8 days, or available soil moisture above 80% initiate brown center formation. Incidence of brown center and hollow heart also increases with periods of stress caused by high or low soil moisture, especially if heavy rains occur suddenly after a dry spell. Large tubers are more prone to develop the disorder, so using closer spacing and avoiding skips in the row can reduce incidence of brown center and hollow heart. There are also differences in the susceptibility of potato varieties to both of these disorders.

--Written by Susan B. Scheufele


News

MDAR Natural Disaster Recovery II Program - Open for Applications

Program covers weather related losses from 2023–2024

Farmers who suffered losses in 2023 and 2024 due to weather may be eligible for this one-time loss-recovery program. Crop, infrastructure, timber, and other losses totaling more than $2,500 may be eligible. 

Applications are open until September 30. Please read the RFR carefully for details about eligibility and reporting requirements.

This block grant program, funded by USDA and administered by MDAR, will cover portions of eligible losses, including: 

  • Crops, such as fruits and vegetables
  • Future economic losses from the loss of perennial plants
  • Infrastructure, such as buildings and plasticulture
  • Timber
  • Bare-ground practices necessary to mitigate land loss. 

Losses for most categories must represent 15% of the value of the lost crop or infrastructure, and claims must total $2,500 or more for each applicant. All eligibility requirements and additional details can be found in the RFR under “Attachments” at COMMBUYS link here.

Deadline for applications is September 30, 2026 at 4:00pm. Late applications will not be considered.

A video explanation of the program, including a walk-through of the application form, can be found here. 

Questions about the program may be submitted to ndr2[at]mass[dot]gov (ndr2[at]mass[dot]gov) before August 21. Answers to general questions, but not questions about specific applications or circumstances, will be posted online here.

$5 Million Available for Section 514 On-farm Labor Housing Loans

USDA Rural Development has released $5 million for Section 514 loans to build or rehabilitate on-farm housing for domestic farm laborers. Applications accepted on a rolling basis. Eligible applicants are individual farm owners, family farm partnerships or corporations, and farmer associations.

How to Apply: Email Northeast MFH Processing & Report Review at MFHprocessing1[at]usda[dot]gov (MFHprocessing1[at]usda[dot]gov).

For more information, see the program website here, or the USDA fact sheet here.


Events

Great Lakes Tek Flex

When: September 10–11, 2026

Where: Southwest Michigan Research and Extension Center, Benton Harbor, MI

Registration: Early bird registration is open now until September 1, regular registration after that.

This even is outside our typical event advertisement area, but it is the largest relatively close opportunity to see such a wide range of novel agricultural technologies. Event organizers expect that at least 15 companies will be showcasing their technology at this event. We wanted to put it on your radar for folks who may be interested.

Temporary Fence Installation & Maintenance, and Pepper Maggot Monitoring

When: September 17, 2026 from 5-7pm

Where: Heart Beets Farm, Berkley, MA

Registration: Coming Soon!

Don't have tens of thousands of dollars to drop on permanent deer fencing? Many farmers in our region find themselves in this situation or can't justify the cost of installing permanent fencing on leased land. Heart Beets Farm in Berkley MA installs and manages temporary electric fencing systems each season to protect their certified Organic produce from deer intrusion. Join us to see their setup in action and discuss the benefits and challenges of such a system. We will address fence installation, maintenance including keeping a "hot" electric line and managing weeds along the fence line, and what to do when deer intrude anyway. This is a great opportunity to see practical solutions you can employ on your own farm, and brainstorm strategies with fellow farmers. Also, UMass Extension will be joining to talk about Pepper Maggot, identification and strategies for dealing with this issue on your farm. 

Pesticide Storage and Handling

When: Tuesday, October 13, 2026 from 4 to 6 pm

Where: The Joseph Troll Turf Research Center, 23 River Road, South Deerfield, MA 01373

Registration: REGISTER HERE. This event is free but please register in advance. 

At this event we're going to focus on the best management practices for pesticide storage, mixing, and handling. Perhaps not the most flashy topic, but one that can keep you safe, save you time, and prevent uncontained spills. We're brining in speakers from Wilson Farm, who by their own account have "at least one of the top three best pesticide storage facilities in New England." By our account, it's by far the best one we've seen. Come with photos of your own facility if you want to prove us wrong. We'll also tour the pesticide storage facility at the UMass Turf Research Farm and hear about their motivation for updating it. Bring your own stories and questions about pesticide storage as well. If you have a question you don't want tied to your name, feel free to submit it here and we'll do our best to come prepared with an answer. There will be some hands-on activities and a facilitated discussion to share and learn from each other.

This is the second event in our "From Tip to Tank: Pesticide Applicator Laboratory Series." There's no need to have attended the first event to join for the second! The series was funded by the Northeast Risk Management Education program and is designed like a laboratory class, where we actually do the thing rather than just talk about it.

*This event has been approved for 2 private certification credits.*

This work is supported by the Northeast Extension Risk Management project award no. 2025-70027-45395, from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.

2026 New England Vegetable and Fruit Conference

When: Tuesday–Thursday, December 15–17, 2026, 8am–6pm daily

Where: Doubletree Hotel, 700 Elm St., Manchester, NH 03101

Registration: Before November 30, $130/person, or $100 for additional attendees if registering as a group. Students $60. Registration capped at 1,400. REGISTER HERE

The NEVF Conference includes more than 25 educational sessions over three days, covering major vegetable, berry and tree fruit crops as well as various special topics. A Farmer-to-Farmer meeting after each morning and afternoon session will bring speakers and farmers together for informal, in-depth discussions on certain issues. The extensive trade show has over 120 exhibitors.


CONTACT US

Not sure who to contact? Email umassveg[at]umass[dot]edu (umassveg[at]umass[dot]edu). 

John Galvan | 413-316-2307 | jgalvan[at]umass[dot]edu (jgalvan[at]umass[dot]edu) 
Small fruit specialist

Maria Gannett | 774-205-0042 | mgannett[at]umass[dot]edu (mgannett[at]umass[dot]edu) 
Weeds specialist

Genevieve Higgins | 413-545-8396 | ghiggins[at]umass[dot]edu (ghiggins[at]umass[dot]edu) 
Vegetable specialist

Lisa McKeag | 413-658-8631 | lmckeag[at]umass[dot]edu (lmckeag[at]umass[dot]edu) 
Vegetable and fruit food safety specialist

Susan Scheufele | 508-397-3361 | sscheufele[at]umass[dot]edu (sscheufele[at]umass[dot]edu) 
Production agriculture team leader, vegetable specialist

Alireza Shokoohi | 202-430-4515 | ashokoohi[at]umass[dot]edu (ashokoohi[at]umass[dot]edu) 
Entomology specialist

Hannah Whitehead | 413-658-8700 | hwhitehead[at]umass[dot]edu (hwhitehead[at]umass[dot]edu) 
Cut flowers specialist, on maternity leave until September 2026


Vegetable Notes is co-edited by members of the UMass Extension Vegetable Program. For general feedback or inquiries, email umassveg[at]umass[dot]edu (umassveg[at]umass[dot]edu). All photos in this publication are credited to the UMass Extension Vegetable Program unless otherwise noted.

Where trade names or commercial products are used, no company or product endorsement is implied or intended. Always read the label before using any pesticide. The label is the legal document for product use. Disregard any information in this newsletter if it is in conflict with the label.

The University of Massachusetts Extension is an equal opportunity provider and employer, United States Department of Agriculture cooperating. Contact your local Extension office for information on disability accommodations. Contact the State Center Directors Office if you have concerns related to discrimination, 413-545-4800.

Vegetable Notes Sponsors

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Ways to Connect

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  • Join the NEVBGA
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