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korney19

WEEKLY Late Blight Updates & Counties Infected

korney19
14 years ago

This was updated as of yesterday I believe, it also listed NY counties reporting LB as well as surrounding states reports...

Also, the Late Blight FAQs pdf file was updated 7/29.

Weekly Late Blight Update

Late Blight FAQs pdf file (requires Adobe Acrobat)

ALSO, there is a "Late Blight: Corrections of Misinformation" sheet!

Hope this helps.

Comments (56)

  • mulio
    14 years ago

    SporapaloozaTM - a NE summer long festival of mud, foul smelling air and communicable diseases

    Featuring Paul Schaffer and the Late Blight Band, The Dead, Gray Day, Wilty Nelson, Spore Foggy Fog and the Fungees.

  • albertar
    14 years ago

    I'm in Suffolk County, but haven't seen late blight on my plants...YET. Alot of yellowing of leaves yes, but not late blight by the online pictures of it that I've seen.

    All in all, its been a very crappy season weather wise for tomatoes, I've gotten maybe 10-12 ripe cherries and nothing ripe on full size tomatoes.

    Alberta

  • laura_k
    14 years ago

    Carolyn- I don't have a vast knowledge of growing but do you think you could over-winter some healthy cuttings of the rare plants you are growing till next season? Or is that not something that can be done?

  • luvahydrangea
    14 years ago

    I'm spraying daily and have had to destroy yet *another* tomato plant today. When I think of all the hard work I put into the garden this year and how healthy and productive it was a month ago, I just can't believe I'm looking at the same garden. I don't think I will grow tomatoes for a couple of years after this.

    I worry about some home gardeners trying to compost the diseased plants. I hope the word is getting out on how to dispose of the plants. I would hate to think that diseased plants are ending up in the city's compost.

    Thanks for posting the links.

  • lionheart_gw (USDA Zone 5A, Eastern NY)
    14 years ago

    Yeah, the whole season absolutely sucks for tomatoes. The peppers are doing a bit better, but not by much.

    Hopefully, we'll be able to recoup a bit in August. The few July tomatoes that were brought inside to ripen were mealy, watery, and bland; even those varieties that were tasty last year. Spitters.

    I'm a bit WSW of Albany and have not seen any LB. Like the poster above said, "Yet". I check the plants every day. I haven't seen any at the nursery either, nor the farm stand that sold their own tomato plants in June (I purchased a few of those). But, we can't take anything for granted and must remain vigilant.

    Good luck, folks!

  • carolyn137
    14 years ago

    Carolyn- I don't have a vast knowledge of growing but do you think you could over-winter some healthy cuttings of the rare plants you are growing till next season? Or is that not something that can be done?

    *****

    Laura, I'm pretty sure I have enough seeds for the most important ones so would just have to have Martha in VA raise my plants for me next year as she does every year.

    There's no way I would try to keep cuttings going over the winter and to be honest, I don't even see why some folks do it. ( smile)

    Carolyn

  • Fred_in_Maine
    14 years ago

    Korney,

    IÂm in Portland, Maine. Zone 4b/5a. This morning I visited a community garden located 600 meters upwind from my garden. It was a very frightening sight  IÂve never seen such devastation. There is not a single tomato plant in that enormous community garden that has not been consumed, crunched and eaten by LB.

    IÂve been lucky. Thanks to this forum, I learned of the LB warning very early and immediately started spraying Daconil and removing anything that looked suspicious. So far so good.

    At this stage IÂm only seeing some Septoria and EB on leafs. Those leafs get clipped and bagged immediately. IÂve continued to spray Daconil weekly. My garden is healthy but painfully late.

    Fred in Maine

  • garyt33
    14 years ago

    Add North Central Connecticut to the list. All plants gone in a week.

  • Fred_in_Maine
    14 years ago

    Carolyn,

    You & I are neighbors in the same zone. In Portland I suffer the same exact weather a few hours after it assaults you.

    IÂm really bummed that the rains of June didnÂt allow you to safely get your Toms in the ground on time. Without a freakishly late frost and a blazing New England September, your assessment of some precious new varieties might be lost to you, and by extension to the world of tomato lovers. You are the Tomato Goddess. When you hurt, we hurt.

    I took a huge risk and put my seedlings in the ground (raised beds) dangerously early. Fortunately May was frost-free, warm and sunny, so my Toms had a good chance to establish themselves before the monsoons hit.

    With the sun returning in July, all of my 36 tomato plants (25 varieties) have now set fruit. The Last Place award goes to Black Prince which finally set fruit two days ago.

    Some Toms set fruit as early as mid-monsoons (Parks Whopper on June 16 Â go figure!). Others set fruit in late monsoons of June (BonnieÂs Grape, Big Boy, Early Girl, Cherries). Everything else set fruit over the course of JulyÂs sun and warmth.

    Other than some cherries and Yellow Pears in my garden, IÂve not seen nor heard of a single blushing Tom to be found anywhere in Maine.

    Fred in Maine

  • jtcm05
    14 years ago

    "I'm spraying daily and have had to destroy yet *another* tomato plant today."

    Spraying what daily???? Hopefully not a labeled fungicide. That would be completely irresponsible and illegal.


    "Add North Central Connecticut to the list. All plants gone in a week."

    Sorry to hear that. I've been fighting an outbreak with weekly spraying since July 3. I seem to have gained a certain level or control, but i still see signs of it every couple days. Hopefully you did the responsible thing and disposed of the plants quickly so as not to be a cause of infections to your neighbors.

  • watboy
    14 years ago

    omg! i found 4 plans in the backyard that only had about 3 to 4 leaves affected all other on side of house i pulled and put into bags. so the 4 that had only a few leaves i removed the leaves and sprayed with fungicide. is this a good idea? is it possible to save these 4 plants? 2 of the plants have about 15 tomatos each very large sized. or should i destroy them? any reccomendations?

  • reginald_317
    14 years ago

    And watboy, I now know of several folks whose plants went from OK, to LB in just 2-3 days...Yea, that is my understanding of p infestans. And it has been confirmed to be here (western PA) by lab tests done by or at the request of the local PSU Ag Extention. I have no signs YET, BUT I will not be surprised if I get wiped out. The local Extension agent told me that he/they think that it was vectored by tomato seedlings that were grown in some southern states and sent to local nurseries. I suspect that many fungi like cool damp conditions which have been prevalent here so far this "summer."

    Reg

  • TJG911
    14 years ago

    ====>" * Posted by watboy (watboy@hotmail.com) on
    Thu, Jul 30, 09 at 10:52

    my friends I went to las vegas on vacatuion with my gf. i left a beautiful lush garden tons of green fruit. i cam eback nothing was left of my lush green garden my 30 tomatoe plants were grey to the stems, tomatoes were had nasty spots on them and most leaves had spots or were already grey. i had sprayed daconil for 3 months every 4 days due to the rain. i had not seen any signs of blight when i left and i also had not seen the stories about it until i got back and started reading posts. i'ma grown man i never cry i almost did. my gf cryed because she knows how much work i out into it."

    sorry to hear this, it's heart breaking to say the least.

    look, i'm no expert, i know the fungicides that everyone is spraying as a preventative are what all are hoping will save their plants. i'm sympathetic to your fears and wishes, believe me. i'm organic and did nothing to protect my plants. when i read how serious this is in this area i panicked and started to look for an organic solution. now i am not saying this cures or prevents LB, all i can tell you is my experience so far.

    i started to spray a milk solution on my plants about 2 weeks ago. within a week i found late blight on 1 plant. i took it out immediately, much to my regret today. i sprayed a 2nd application of the milk solution. tomorrow i will spray a 3rd. trust me it's raining here constantly so it's not like i'm in a dry sunny spot. a few days after taking out that plant i found LB on 6 other plants! doomed is all i thought, done before i get a tomato.

    i was out there on saturday and i was surprised at the condition of my plants. good, actually better than they looked earlier in the week. the LB does not seem to have advanced, i expected the plants to be in the final stages of death. i quoted watboy's post as an example of how fast i have heard LB is in taking out tomato plants.

    i don't know if the fungicidal properties in milk will protect my plants from further LB advance or will cure them. as of now i am hopefull they will live a little longer. the fact they have not totally collapsed already makes me hopeful.

    there is very little information on using milk as a fungicide but it does possess anti fungial properties. spraying a milk solution does cure powdery mildew in curcurbits for what it's worth. maybe it can help with LB. i know this sounds like you can cure cancer by eating grapefruit but if you want to try it i'll post the mixture for you. this makes 2 quarts of milk solution that you can apply with any spray device -

    2 cups of milk (whole milk is supposed to be better but any will do)

    if you use whole milk then use 1 teaspoon of dish detergent NOT anti bacterial or it'll kill all the beneficial bacteria on your plants! the soap helps the fats in the milk to stick to the leaves.

    2 quarts of water

    optional - add appropriate quantity of liquid concentrate of...

  • anney
    14 years ago

    If you want to apply a product with a great deal of research supporting it, organic Serenade Fungicide is listed as a "suppressor" of Late Blight.

  • korney19
    Original Author
    14 years ago

    I just posted this in the Boston Globe thread...

    A friend just bought Southern Ag Liquid Copper Fungicide today, I think he said it was around $7? You use anywhere from 1 to 7 spoonfuls per gallon.

    I'm not saying Serenade doesn't work, but almost all the edu/ag/gov sites are recommending chlorothalonil based products, and probably for a reason.

    The report from the U of Tenn from 2001 said about Serenade:

    "Plots treated with BAS-500, BAS-510, and with Dithane alternated with Quadris had significantly lower disease ratings for Early and Late Blight and the highest marketable yield than the other treatments. Plots treated with Seranade (biological fungicide) had disease ratings not significantly different than the untreated check plots."

    Dithane, by the way, is Mancozeb (manganese & zinc.) Dithane-45 is often on ebay for under $10 or so.

    Someone tried pointing out that they waited too long to use Serenade, but rereading the actual product label, it never mentioned anything about PREVENTING Late Blight--instead, it always says "Late Blight suppression."
    This is for their "industrial strength version" designed for farmers, which is something like 10x stronger than the consumer product! Serenade MAX, 12 lb bag, $159.00.

    Daconil I think I paid $13.77/pt at Walmart; Mancozeb was $12/pt at horseloverz. Daconil/chlorothalonil may be the most economical at 2t to 1T/gal. All I could find for Serenade was 2-6 Quarts/acre. For Serenade MAX, it says 1-3 lbs/acre. It also said:

    "For suppression, begin application when plants are 4 to 6 inches high. Repeat applications on a 5 to 7 day interval or as needed. For improved performance, use Serenade MAX in a tank mix or rotational program with other registered fungicides for late blight control. Use shorter spray intervals under conditions conducive to rapid disease development."

    I'm not about to do the math, but 4" to 6" tall plants, every 5-7 days, at $159/bag......... PLUS use it with or in rotation with OTHER registered fungicides for late blight control??????

  • mulio
    14 years ago

    Im not saying it isnt effective but

    almost all the edu/ag/gov sites are recommending chlorothalonil based products, and probably for a reason

    when those companies fund the research it's tendency to get/be mentioned/considered certainly goes up

  • jtcm05
    14 years ago

    I just don't buy the serenade or milk thing. I have been using that Southern AG copper ammonium based fungicide in combination with chlorothalonil since the 4th of July weekend when i first noticed signs of LB. Label rates say 3-6 tsp per gallon of water for the copper stuff. Ive been mixing with 6 per gallon. Now I have been diligently removing any signs of diseased plant material every couple of days, but in the last few weeks, this is the best my plants have looked in years disease-wise. I've pulled about 8 plants total and initially removed and burned about 4 wheelbarrows full of material. I only removed the plant completely if LB was on the main stem or multiple stems with little chance of future fruit harvest. Otherwise I just stripped the diseased foliage. Lately i only pull a couple handfuls of material every other day or so. I only plan to continue spraying until i can harvest the 16 crossed fruit i have growing. Have already harvested 4.

  • korney19
    Original Author
    14 years ago

    Posted by mulio (My Page) on Mon, Aug 3, 09 at 0:18

    Im not saying it isnt effective but

    almost all the edu/ag/gov sites are recommending chlorothalonil based products, and probably for a reason

    when those companies fund the research it's tendency to get/be mentioned/considered certainly goes up

    I was wondering how long it would take someone to say that... and I just KNEW it would be YOU! Sometimes I think you need to not let your son influence what you write.

    Do you think, if milk worked against LB, (and it's affordable and easy access to everybody), places like Cornell wouldn't recommend it to gardeners for an LB outbreak and instead recommend big corporate chemicals only? Same with Serenade or any other organic. Or any other thing not made by Bayer, Syngenta, Dow, etc.

    When was the last time you heard that "do-all, cure-all, wonder drug" Neem recommended for this LB outbreak? In all the reading, locally & inter[net]nationally I've done, I don't recall any endorsements for Neem.

    You're pretty smart & respected, how do you feel about spraying milk on plants to fight LB?

  • mulio
    14 years ago

    how do you feel about spraying milk on plants to fight LB?

    I dont feel anything about it.

    How do feel about a chemical which specifically works by acting to deplete glutathione - a protective substance which is already found to be depleted in many patients with cancer, Alzheimer's, AIDS, Parkinson's and other neurodegenerative diseases?

    While a healthy person might not notice the effects of depletion, what health effects do you think chronic or even subchronic exposures would have on such individuals with already reduced glutathione levels?

    During its manufacture, Chlorothalonil is contaminated with the carcinogen hexachlorobenzene. This would be one of its "inert ingredients". This may not be accounted for in carcinogenic studies which, in order to be scientific, would only consider the effects of pure chlorothalnil itself.*

    Chlorothalonil's breakdown product is 30x more acutely toxic than chlorothalonil itself and is also more mobile and persistent in soil.**

    *Vargyas, L.D. et al. 1995. Simultaneous determination of chlorothalonil and hexachlorobenzene in technical and formulated materials by capillary gas chromatography. J. AOAC Intern. 78:604-609.

    **World Health Organization. International Programme on Chemical Safety. 1996. Chlorothalonil. Environmental Health Criteria 183. Geneva, Switzerland. p44-52

    Here is a link that might be useful: Fungicide Fact Sheet

  • pennyrile
    14 years ago

    Whole milk, powdered milk, skim milk, daily spraying of Daconil ...

    Has anyone tried spraying Dr. Pepper at 10:00, 2:00 and 4:00?

  • lionheart_gw (USDA Zone 5A, Eastern NY)
    14 years ago

    Is that regular Dr. Pepper or diet Dr. Pepper? :-)

  • korney19
    Original Author
    14 years ago

    The first link at the top of the page has been updated 8/4... many people are mixing up Septoria Leaf Spot and LB! See the WEEKLY link at the top...

  • korney19
    Original Author
    14 years ago

    Bump... sorry this thread got railroaded...

  • mulio
    14 years ago

    Hexachlorobenzene HCB has not been sold in the United States (as an end-product) since its last registered use as a pesticide was voluntarily canceled in 1984. It can be found in chlorothalonil but is considered an "inert ingredient" with no "end-use" and therefore does not have to be disclosed. It also would not be picked up in on health studies of chlorothalonil as only the active ingredients are tested to separate out biases. It is considered one of the top POP's out in the environment and in our food.

    POP = Persistent Organic Pollutants

    Twelve POPs - the "Dirty Dozen" - targeted for a ban on use and production under a U.N. treaty now in negotiation.

    Even though its registeration was voluntarily removed as an end use product why it is still found in foods years after being removed?

    FDA found seven POPs in 155 different foods from 1991 through 1997

    If the half-life of the product is only 1/2-12 year (depending on where it is located) why then is it still found in food? Because it is still being put into the environment though sources like chlorothalinil. It is highly persistent and bioaccumulates in the food chain.

    From ATSRD
    "Impurities of hexachlorobenzene in currently registered pesticides (picloram, PNCB, chlorothalonil, Dacthal®, atrazine, simazine, lindane, and PCP) (Bailey 2001; EPA 1986e, 1993a; Farm Chemicals Handbook 1993) appear to be a continuing source of hexachlorobenzene exposure for the general population. Five of the pesticides containing impurities of hexachlorobenzene (PCNB, chlorothalonil,
    Dacthal®, lindane, and PCP) are used in home gardens, lawn care, and other applications around residences and in urban areas (Farm Chemicals Handbook 1993)."

    What happens to hexachlorobenzene when it enters the environment?

    • Hexachlorobenzene can remain in the environment for a long time.

    • It breaks down very slowly.

    • It does not dissolve in water very well, so most of it will remain in particles on the bottom of lakes and rivers.

    • Hexachlorobenzene sticks strongly to soil.

    • High levels can build up in fish, marine mammals, birds, lichens, and animals that eat lichens (like caribou) or fish.

    • It can also build up in wheat, grasses, some vegetables, and other plants.

    The US govt ATSRD site states:

    "Produce grown in contaminated soil should not be eaten. " that's ironic

    "It is sometimes possible to carry hexachlorobenzene from work on your clothing, skin, hair, tools, or other objects removed from the workplace. This is particularly likely if you work in the chemical or pesticide industries. You may contaminate your car, home, or other locations outside work where children might be exposed to hexachlorobenzene. You should know about this possibility if you work where hexachlorobenzene exposure may occur."

    "Nonpoint source dispersal of hexachlorobenzene in both agricultural and urban settings results from its presence as
    a contaminant in several widely used pesticides. These sources, in...

  • rocklandguyZ8,SC
    14 years ago

    I'm in Rockland County, NY. I have 30 different variety, 19 in the ground, and 11 in large pots around my shed. They were all started from seed & were very healthy when transplanted out. No plants were purchased. Every plant started with the spots starting at the bottom of the plants, yellow leaves, then to the drooping brown leaves. I trim the dead stuff daily, most plants now just have the main stem, branches with no leaves, and green toms just hanging on. Now, from what I can see, it looks like LB that has started with dark spots on the toms, soft rotted spots on partially ripened toms, green toms just turning black on the plant, pink and yellow spots on the toms that turn soft, or the toms just falling off. This is my worst season ever! And the wettest season ever! Paul

  • harvestingfilth
    14 years ago

    Wow! Thanks for the information. I'm also in Suffolk County, NY and right now have no signs of Late Blight. I am also on an island, and growing in a garden that was brand new this spring (no veggie garden since the late 70's on this property). I also grew nearly everything from seed, though I did purchase a few straggler tomatoes late in the season to fill in spaces.

    Aside from an awful infestation of tobacco hornworm that I took care of yesterday, I think everything is fine. All my plants have (sadly, green) fruit and I'm just waiting for some to ripen. I guess this explains why the farmstand price for tomatoes was $2.50/lb today. I will do a closer inspection tomorrow, just to be safe.

  • mscratch
    14 years ago

    Add Penobscot County, Maine.. and the blight has hit the wild blueberry crops in Maine and acres upon acres will be burned.

  • albertar
    14 years ago

    Just as an update to my 7/30 post. I've definitly got LB on one plant. The others have something else, perhaps septoria spot, I'll be darned if I really know how to tell the difference with all the diseases, but the one definitly has LB. What I'm finding is although the other plants have yellowing and browning, and also like a crisping of some of the leaves, the fruit does not seem to be affected like the one with the definite LB, and the non LB plants are still growing like crazy. I will not compost any of them this year, for fear that what ever it is besides LB could just linger and affect next years crop.

    I've read somewhere online that some people are burning their affected plants, but isn't that defeating the purpose since LB is air borne? Another thought, and maybe its just me thinking this way...if the LB plants are bring taken out of the gardens, and being sent to the land fills, won't that also create havoc for next year, or is it true that the disease will not live over winter? This is one very confused home gardener this year.

    Alberta

  • korney19
    Original Author
    14 years ago

    This was from UMASS but methods should apply everywhere.

    IMPORTANT MASSACHUSETTS UPDATE, 7/30

    Update July 30, 2009
    All counties in the state have reported late blight. Potato and tomato that are being sprayed often (5 days apart, more or less) seem to be holding up against the late blight inoculum that is everywhere in the environment. This is the encouraging news: fungicides are working  so far. This is true for fungicide programs with the best systemics and protectants available, and it also seems to be true for the copper hydroxide products that are available if your farm is certified organic, as well  much to our surprise. Copper is working where growers began spraying several weeks ago, before late blight infected the field. For growers who are trying to save an infected field, it is not clear yet what will, and will not, be effective.

    The inoculum is clearly present throughout the state. Fungicides will need to be applied regularly through harvest, for tomatoes, and until tubers are mature and dug green or vine killed, for potatoes. Potato growers are reporting good quality and yield as they begin early harvest.

    Crop loss. However, tomato and potato crops that have not been sprayed are dying rapidly. Late blight is living up to its reputation as a disease that can kill a crop within a few days. Though weÂve had some hot, sunny and humid days, evening rainstorms and >12 hour leaf wetness periods continue to be very regular events. So the weather conditions are still very favorable for this disease. Of course, early blight and Septoria leaf spot are widespread as well. If your field is holding or not infected yet, begin or continue a regular fungicide program.

    After the crop is lost. If your potatoes cannot be saved, mow-kill them. Looking at a field of carefully staked and woven tomatoes covered with green fruit and blackened foliage is very discouraging. IÂm learning that late blight has a distinctive smell. I spoke with a grower about how he typically dismantles a field in the fall: grab all the strings right near the stake, cut them all with a knife. Do this at each stake, and pull out the strings from that section between stakes. After a while you have a bundle of twine in your hand, and the plants are now free of twine. Pull stakes and pile on a wagon systematically. Now you can go through with a rotary or flail mower and chop up the vines and fruit. You have done your neighbors a favor by reducing the capacity of your crop to generate millions and millions of spores that can travel on moist winds to their fields. If your tomato field is beyond recovery, do this as soon as possible.

    {{gwi:2104609}}

    Potato harvest. If your potatoes were mowed or vine killed, can they be left in the ground for the next month, for harvest in September? There is some risk from late blight spores washing into the soil if the vines were infected. However, the ground is probably...

  • mulio
    14 years ago

    Any reports on what the HCB bioaccumulation rate is up too now?

  • krenster
    14 years ago

    In the Poconos, first attempt at a garden this year, new raised bed with composted amendments to truck-in topsoil (no dirt to speak of on our glacial till scree-covered mountain)

    All tomatoes were blemish free and green last week. I thought I'd missed LB due to our remoteness.

    Today I see plants dead or dying and blemishes around stems. I bought these tomato plants at Home Despot (I have no way to start from seed) -- I won't ever do that again, and I knew better but was trying to save some money.

    Question on destroying plants: I've read that I should NOT pull them up by the roots because that would release spores into the air. But if I cut them off at ground level and bag them, aren't I leaving the spores in the ground to fester? Does winter really kill them all off? Do I need to worry about next year if I leave any infected plant matter underground?

    Thanks, everyone.

  • compost_pete-grower
    14 years ago

    Carolyn, I will be happy to send you a dozen or so of my tomatoes. I have some very nice cherokee purple, brandywine ss, and in a few weeks opalka. Also tons of sun gold but I don't how they will ship. Please let me know what you like. None of my plants are sprayed with anything. I can't imagine a tomato lover like you not having some garden fresh goodies. my E-mail is tomatoking@zoomtown.com Mulio, your info is well appreciated. I have grown 800 plants from a seed packet from tomato growers of brandywine suddiths strain and this year in one of the flats a RL plant appeared. I grew it and it has fruit very similar to PL BSS. Is it worth saving seed from and growing next year. I will b/c its so easy but I was interested in your opinion.

  • bcday
    14 years ago

    Posted by kren
    Question on destroying plants: I've read that I should NOT pull them up by the roots because that would release spores into the air. But if I cut them off at ground level and bag them, aren't I leaving the spores in the ground to fester? Does winter really kill them all off? Do I need to worry about next year if I leave any infected plant matter underground?

    Where did you read that pulling plants up by the roots would release spores into the air from the soil? If there are Late Blight lesions on the leaves or stems, that's where the spores get released from -- not from the roots.

    Late Blight doesn't live on plant roots nor do the spores live for very long in the soil by themselves. They die quickly unless they land on a suitable plant leaf or stem to grow on. So you can safely just cut the plant stems off at ground level and leave the roots behind. There won't be any Late Blight festering on the tomato plant roots.

    Late Blight does infect potato tubers, but potato tubers are not "roots", they are modified stems and can develop lesions if spores get down through the soil onto them. If the infected tubers survive the winter and sprout next spring, they will infect next year's crops. But if the potato tubers are killed by freezing over the winter, any Late Blight that is on them will not survive. So if you have a potato patch in the garden, don't pile mulch over the potatoes to keep them from freezing.

  • korney19
    Original Author
    14 years ago

    Looks like the FAQ link has been updated 8/19.

    Kren, Late blight needs a host plant to live on, if you remove it from the ground you can end the cycle. Also see the FAQ link in the opening post.

    1. Can late blight be exacerbated by handling plants, such as during pruning and trellising tomatoes?
      Possibly, but the quantity of spores dislodged by the plant movement that occurs during these activities might not be more than what would occur naturally by wind. Human impact on pathogen spread is expected to be much less with late blight than with a pathogen like the one causing bacterial canker, which is in the sap of plants, can be picked up on hands and any tools, can be deposited while handling another plant, and can enter a plant through wounds that occur during pruning and trellising. Better spray coverage can be achieved when plants are pruned and trellised rather than left to grow on the ground.

    2. Could the late blight pathogen survive on tomato cages and stakes between seasons?
      No. Therefore it is not necessary to discard or even disinfect the cages or stakes to manage this disease. Stakes and cages should be disinfected however, especially if bacterial diseases also developed in the planting.

    3. Could the late blight pathogen survive in soil between seasons?
      Unlikely except in affected potato tubers. This is an obligate pathogen that is thought to only be able to survive in living plant tissue in the northeastern US. It can produce a specialized structure that would enable it to survive without living plant tissue, but this requires that the pathogen reproduce sexually which it is not thought to be able to do in the northeastern U.S.
      When late blight has previously developed in this region and the pathogen population has been examined, only one "mating type" has been found. This is the term used for the pathogenÂs equivalent of male/female. Thus the pathogen has only been able to reproduce asexually. The characteristic white growth that develops on late blight affected tissue contains many asexually-produced spores. Both mating types have been found in Florida.

    4. Could the late blight pathogen survive between seasons on perennial weeds that it is able to infect (e.g. bittersweet nightshade and hairy nightshade)?
      No. This is an obligate pathogen that needs living plant tissue to survive. It only infects foliar tissue of weeds. Since the pathogen cannot infect roots, it cannot survive on weeds in areas where foliage is killed by cold temperatures. In the Northeast, potato tuber is the only plant tissue it is able to survive in.

    5. Could the late blight pathogen survive in or on tomato seed?
      No. Fortunately this pathogen is not able to get inside seed and it does not produce a type of spore that is able to survive the dry conditions on the outside of a seed. Thus there is no concern that late blight will develop as a result of growing plants next year from seed that were in tomato fruit affected by late...

  • lionheart_gw (USDA Zone 5A, Eastern NY)
    14 years ago

    I'm in Albany County, NY.

    I've lost almost all tomato plants to LB. They've been bagged and solarized and have been going out with the trash every Friday.

    There are a few plants that are hanging on pretty well, and I've been spraying them religiously every week.

    They are (1 of each):

    1. Sun Gold. Had a few leaves with LB removed a couple of weeks ago. So far, no additional signs of disease.

    2. Black Krim. A volunteer from last year. No LB yet. Harvested only 2 tomatoes that started to blush so far. They were tasty, as always. Lots of good looking green ones on the plant. Fingers crossed (which makes it hard to spray). :-)

    3. Costoluto Genovese. Another volunteer from last year. LB tried to get a hold but doesn't seem to progess very quickly on this plant. This guy is a sprawler. It's not a tomato that excites me (but it's okay), so I wasn't going to go out of my to save it. Now that the field is down to a handful of plants, I might give it a little more effort. The rest of this ambitious grower is still looking healthy.

    4. Nebraska Wedding. No LB yet, but it's running out of time for being productive.

    5. Pruden's Purple. Has had LB on the leaves. Many of them. LB leaves removed when found. Except for the newer top leaves it's virtually naked. Stems are still clean. Fruits are huge and not yet showing signs of infection, but if they don't start blushing soon it may all be for naught. This one is day-to-day.

    All of the Brandywines are gone.

    Amish Paste was the first to get LB, along with an unidentified volunteer, and both are ancient history.

    The CPs hung on for a while, but they had to be destroyed too. At least we got 3 tomatoes before LB came to town.

    Started out with about 30 tomato plants. Down to 5 that are precariously hanging on.

    I am aware of the funky smell that accompanies late blight; it hits my nose pretty quickly. It has notes that are similar to a fetid, rotting carcass. I could also smell it on my hands after destroying the plants. Yuck. The nose knows, lol.

    It's really kind of funny; last Thursday, after daily inspections, the disease seemed to be contained. I was feeling pretty hopeful at that point. There had been no new signs for several days prior. By Sunday 6 of the remaining 11 plants looked like a disaster area. They're gone now.

    Those of us in the cold zones AND in LB territory are playing "beat the clock" on two fronts -- rate of disease progression, and the amount of productive growing season remaining (not much).

    Dr. Carolyn, I hope your plants are hanging in there!

  • krenster
    14 years ago

    >

    Thanks very much for all the info. I'm still confused, though, about the roots. Here's what I read this week:

    "DO NOT pull affected plants because this process can dislodge spores into the air where they can be wind-borne to neighboring plantings of tomatoes and potatoes."

    This is from the Penn State Master Gardeners blog on the Morning Call website in Allentown.
    Link:
    http://blogs.mcall.com/master_gardeners/2009/07/late-blight-what-should-the-home-gardener-do-destroying-plants.html

  • jtcm05
    14 years ago

    Handling the plants in ANY way can spread any spores that are present. Not much you can do about that. Better to get rid of the plants, or better yet, burn them.

  • bcday
    14 years ago

    Kren, maybe the reasoning for #3 in that list was that when people pull a plant up, they shake the soil off the roots before they discard the plant. That kind of vigorous shaking would release millions of spores into the air from the lesions on the leaves and stems.

    I think #3 would have been better included in #4 instead of being listed as a separate item. Taking #3 and #4 together would mean that rather than pulling the plant up by the roots, you should put a plastic bag over the plant and then cut the stem. That way, as many spores as possible will be trapped inside the plastic bag instead of being shaken free to float away on air currents and infect healthy foliage.

  • cleo88
    14 years ago

    Add Norfolk County, Massachusetts.

    Went on vacation last week - when I left, all was hunky-dorey. When I came back... well, do I need to say it? I have two beds about 15 feet apart. The bigger bed had about 1/3 of the foliage decimated. The smaller bed doesn't seem affected yet.

    I am spraying with Serenade, the only solution (organic) recommended by my local nursery, which by the way smells exactly like vomit, but whatever. I will let you know if I can save anything. I sprayed everything in both beds. It's very sad - my first KBX, a huge one, just started to blush, but it was had the late blight "bruise" on much of it and I had to toss it. Wah. When I think how I babied that plant from seed...

  • jtcm05
    14 years ago

    you just started spraying serenade or were before you left?

  • tsugajunkie z5 SE WI ♱
    14 years ago

    Eight counties in Wisconsin have reported late blight since first discovered here in early August. Since there are many potato farmers in the state, the University of Wisconsin is asking homeowners to report incidents to them so they can track the outbreak. The method of destruction they suggest is "cut them off at the ground, seal them in a plastic bag and leave them in the sun until the plants are clearly dead, and then toss the whole package in the garbage".

    tj

  • fearlessem
    14 years ago

    Hi folks --

    I've got a question. I live in a county totally hit by the late blight -- meaning I don't think my plants are going to be spreading it to someone else who doesn't have it yet. My plants just took a turn for the worse in the past few days. They are starting to produce some tomatoes now though. Is there any reason I can't basically wait until the plants have ripened whatever tomatoes they can before plastic bagging them?

    I'm at least relieved to see that this thing can't overwinter in the soil...

    Thanks in advance for your answers...

    Emily

  • tsugajunkie z5 SE WI ♱
    14 years ago

    If you do decide to harvest them it has been suggested they will not keep well so don't try to can them.

    tj

  • bcday
    14 years ago

    If you leave the fruit on the infected plant, Late Blight spores from the leaves and stems will spread to the fruit which will rot instead of ripening. It's best to pick the fruit and bring it indoors to ripen and then get rid of the plant. Check out the pics of infected fruit here:

    Here is a link that might be useful: Late Blight on tomato fruit

  • bcday
    14 years ago

    Another pic of infected tomato fruit

    Here is a link that might be useful:

  • fearlessem
    14 years ago

    Thanks for the replies folks! Since the blight as of yet isn't affecting the fruit itself, I guess I'll leave it so long as I'm getting some of the fruit ripening. Will definitely not can them.

  • korney19
    Original Author
    14 years ago

    So it's seven months later... who lost everything? Who bagged & disposed of their plants? Who burned them? Who had fruits turn brown?

  • gardningscomplicated
    14 years ago

    So I just get done setting up 2000 tomato seeds for germination, and the first thing I see here is BLIGHT UPDATE!!! Freaked me out. Then I looked at the date:)

    I lost almost everything to slugs last year. Then the blight finished off the rest. The extension office said the blight doesn't overwinter here. So not to worry. But now that I think about it, how fast would it spread from someplace south of here where it doesn't get killed off by the cold? I don't wanna think about it.

  • korney19
    Original Author
    13 years ago

    Didn't someone say it's already in Wisconsin this year??

  • korney19
    Original Author
    13 years ago

    New reports the week of 6/22-29:

    Reported on 6/24: Late blight has been confirmed in tomatoes on an organic farm in Harrison County, OH. Harrison County is in east/central Ohio, one county west of the Pennsylvania border.

    Previous reports (most recent first):

    On 6/19 late blight was reported on tomato in a community garden in north central Suffolk county, NY. The gardeners were taking out all their tomato and potato plants.

    On 6/17 late blight was confirmed on tomato from a home garden in New Haven county, CT. The plants had been grown from seed by the gardener.

    Outside our reporting area, a 6/21 find on potato in Michigan.

    The week of 6/8-15 there were two additional late blight reports in Pennsylvania. Both were on tomato transplants in home gardens. One find was in Somerset Co. (south central PA), on a plant purchased at a local greenhouse. The other was from Beaver Co. (near the Ohio border), unknown source.

    Late blight was found in a greenhouse in northwestern Pennsylvania in mid-May. It was being monitored and treated to prevent spread.