QuestionQUESTION: I live in eastern NC where summers are ho=t and long and winters are mild
and short. I grow a vegetable garden (2500 sq. ft.) every year from about
March to December and I try my best to be as "organic" as possible. I have
beautiful and plentiful results and I have very little issues except two. All my
Kale vegetables (collards, cabbage, cauliflower, broccoli, etc.) get completely
eaten by what I call cabbage worms. Other people have referred to them as
army worms or cut worms. They are green worms with no other markings
and range from tiny to about an inch. I have tried everything I know (I hand
water them, pick them off by hand, made a water/worm blender solution,
commercial organic sprays, etc.). I have tons of lizards, frogs, toads, snakes,
birds, etc. However, no matter what I try, these worms can completely
destroy all my plants in a few days. The only thing I have found that works is
to spray my plants with a pesticide such as Ortho. And it works great. I just
don't want to put these plants in my body or the bodies of my family. What
can I do to avoid using these awful chemicals? As I said, experimenting can
be futile since these worms can destroy everything in less than a week. I also
lose my peaches and blueberries to Japanese beetles if I don't use pesticides.
Please help!!!
ANSWER: Jay, LOSE the Ortho.
ESPECIALLY since you're EATING these vegetables.
Ortho's bad enough to use on flowers and Lawns. But when you put it on your own food, you don't just wrecking the Earth. You wreck your own health and the health of your family.
Boy, am I glad you wrote.
What CAN you do? First, let's look at some basic gardening principles.
You saw or read Grapes of Wrath? All that Depression Dustbowl stuff could have been avoided if those poor farmers had only know about Crop Rotation.
Why?
Because Crop Rotation does 2 things that will also provide some relief for YOU.
One, you don't deplete the Soil of the same nutrients that one single Crop needs a LOT of, over and over, year after year, until those nutrients are eliminated. You replenish the Soil. You give it a rest. It breathes for a year. The next year, it exhales.
And Two, you avoid the same Bugs over and over. And this is really amazing. Because Bugs are not a problem during their first year. They are only a problem after the second year.
Just by planting a different crop each year, you stop Diseases and Insects from getting a foothold and building a monopoly on the same plants planted over and over in the same spot. Like that old Gardener's Saying, An ounce of prevention is worth a pound of cure.
There's a lot written about the principles of Crop Rotation. Of course, a lot of it is hocus pocus. I don't recommend you read any of THAT. But Scientists post Research on the internet, too. Any state with a farm publishes studies and analyses on the internet for its farmers -- and for folks like us. All the Cooperative Extensions post them. Crop Rotation is a tried and true, centuries old farming system, and it will work for you, too.
University of Idaho tells its potato farmers dealing with Diseases, Weeds and Insects, 'Increased Crop Rotation can reduce these problems.' You can read some of their comments here:
http://www.uidaho.edu/pses/research/synopsis/cropmgmt.htm
Rodale Institute -- the people who put out Organic Gardening magazine -- manages a website and program called The New Farm. Its trademarked slogan is 'Healthy Soil = Healthy Food = Healthy People'. Have a look at their pages on Crop Rotation, particularly their essay, 'Cover Crops for Vegetable Production':
http://www.newfarm.org/features/1002/crop_rotations/page2.shtml
Your 'Kale Vegetables' are Brassica Family crops that pose their own pro's and con's in your battles with bugs. Broccoli, Cauliflower, Brussels Sprouts, Turnips, Horseradish, Radishes and some other vegetables generate a natural chemical called GLUCOSINOLATES. If you till the spent plants in at the end of a season, then rotate to another NON-BRASSICA Crop, or even just a Cover Crop, they'll decompose all Summer and release those Glucosinolates into the Soil.
The nicest thing about this is that Glucosinolates are NATURAL INSECTICIDES (plus they demonstrate anti-Cancer properties in the laboratory). They also act as Fungicides because they contain Sulphur. Cornell University School of Agriculture tells us these weapons 'sit benignly inside a cell until it抯 punctured -- usually by predator feeding. They then mix with certain enzymes from other cells, reacting to yield sharp-tasting, sometimes toxic compounds.'
http://bti.cornell.edu/featuredResearch1.htm?id=2009
You taste Glucosinolates when you eat them -- they give these vegetables their sharp, bitter flavor (and probably make them more un-popular with kids and, remember, GWB). The more Glucosinolates, the more bitter the flavor, the more anti-insect. When you rotate them into plots where you grew other vegetables the prior season, you ambush unsuspecting, vulnerable bugs and wipe out the hostile troops in that section of your garden.
http://www.newfarm.org/features/1002/crop_rotations/page2.shtml
There is another benefit to growing your vegetables without bad chemicals. You don't wipe out friendly insects and micro-flora like you do with Ortho products. These are powerful forces that you would not want to reckon with if you were an insect predator or pathogen. There's ongoing research on these micro-alliances in the Soil, and every month, we learn something new. Take the studies at the U.S. Dept of Agriculture by Robert Kremer, a microbiologist. Summarized at the Cornell website, Kremer discovered that 'certain Rhizobacteria, when provided with organic matter, keep Weed seeds from germinating.'
That's -- excuse the expression -- ground-breaking stuff. All consistent with what we've been learning for years and years.
Cornell summed the study up thusly: 'By producing toxins and excessive concentrations of plant growth hormones, root cells of weeds rupture and leak, replenishing the organic matter for the Rhizobacteria. Once weakened by the Bacteria, Weeds are less able to compete with other plants, and they become more vulnerable to other control measures. These Bacteria seem not to affect crop plants. One of the most suppressive systems he examined was an organic Strawberry field.'
I can write pages and pages on this but in a nutshell that's the deal. Let me know if you would like more info and I'll be happy to pour it on. Probably even happier than you! Your followups invited.
---------- FOLLOW-UP ----------
QUESTION: I appreciate your in depth answer. I grow a large variety veggies, herbs, and
fruits...about 50 different kinds. I usually grow enough to feed my family and
put some away to last through the non-growing months. I always rotate
(except for the fruit trees and vines obviously) but I don't know exactly the
science and how I should do it, I just grow each vegetable in a different
location each year. Are there any rules I should follow?
What can be done for the Japanese beetle problem? I have found the
following website on JB control:
http://www.forestpests.org/japbeetle/
and I am really interested in the biological control solutions since I am a
microbiologist (Clinical Laboratory Scientist). I am also going to look into
setting up some traps too. I am willing to try these non-chemical solutions
for a couple of years. But since this foreign insect is now established in NC, I
don't think I can get rid of all of them by myself. I have to use Malathion to
get any peaches or blueberries. Is there a "least toxic" chemical solution if
these efforts do not work? Have you any knowledge to share about my JB
issue? Thank you so much!!!
AnswerYou've asked two very different questions that I think need to be addressed in depth. And I'm limited in how much I can put down in a single answer. The followups, as I type them, tend to crash before I get them in, and the long answers sometimes corrupt into alphabet soup. But I'm going to cautiously answer them as best I can and this is very hard to do because I have to limit my words. And I do love to talk. We New Yorkers are like that. If you have more followups, best thing is to send me separate questions. There's no limit right now as it's the slow season right now, and I don't get too much to do.
Pull up a chair, my friend. Have a seat.
We抣l begin with the rules about Crop Rotation. You抳e got a head start. You just need to fine tune. Fortunately, you are highly educated, so you won抰 be easily overwhelmed by data and long words.
In the 1950s, an English farmer named Newman Turner wrote the bible of crop rotation, called 'Fertility Farming'. He updated the principles of crop rotation. We抳e learned a lot since then, but you can read this book online as time allows:
http://journeytoforever.org/farm_library/turner/turnerToC.html#contents
Vegetables classified in the same botanical groups share common cultural needs, and they battle the same insects and diseases.
For Crop Rotation to succeed, you must know which of your 50 fruits and vegetables belong to the same Family. Once you know this, group them together. This is a critical step.
For Winter, a crop of Green Manure -- Alfalfa is one of my favorites -- protects nutrients from erosion; you just dig it in the following Spring.
The Brassica Genus is a LOT of vegetables, more than any other group. Brassicas are officially 'Brassicaceae'. Some are leafy, some are roots, some are flowering stalks. Broccoli, Brussels Sprouts, Cabbage (Red and White both), Cauliflower, Kale and Mustard are Brassicas. If there's one outstanding quality they share, it's probably that they are incredibly healthy. So if you are not sure where to classify your vegetable, if it's packed with vitamins, it's probably a Brassica. For this reason, Brassicas are VERY demanding when it comes to nutrients and they use a LOT of Vitamins and Minerals.
慡olanaceae?-- the Nightshade Family -- includes Potatoes, Tomatoes and Eggplants.
慍henopods?or 慓oosefoot? aka Chenopodiaceae, includes Beets, Spinach and Swiss Chard. This family is famous for its C4 Photosynthesis capabilities, but we won抰 go into that right now.
Beans and Grains belong to the Fabaceae family, aka 'Legumes', famous for being high in protein. Peas, Lima and String Beans, Lentils, Soybeans are all Legumes. We LOVE Legumes most of all because the plants independently fix Nitrogen into your Soil. By slow-releasing N throughout the season, you avoid the quick dose that stimulates Weeds. Plus you don't destroy friendly Soil Microbes with chemically based Fertilizer Salts.
Alliums -- 慉liaceae?-- include Shallots, Garlic, Chives, Onions and Leeks. And Jerusalem Artichokes (慉llium sativum?.
Cucurbits -- 'Cucurbitaceae', aka the Gourd Family -- includes Summer and Winter Squashes, Zucchini, Pumpkins, Cucumbers, Melons and Gourds.
Hot Chili Peppers and Sweet Bell Peppers are classified in the Capsicum Annuum Grossum Group.
The huge Sunflower Family -- 慉steraceae?-- includes Lettuce and Artichokes as well as Dandelions, Thistle and Dahlias.
慤mbelliferae?includes Parsley, Carrots, Parsnips and Fennel. This is sometimes called the Parsley Family.
Sweet Potatoes are members of the Morning Glory family, 慍onvolvulaceae? introduced to Europe by Columbus. Yams however are members of the starchy, Potassium-rich Yam family, 慏ioscoreaceae,?known for growing so deep underground it is hard to harvest them.
Divide your plot up into 3 different sections. Then vow NEVER to plant anything from the same Family in the same plot 2 years in a row. You抣l find a useful illustrated diagram at this British website, 慓arden Organic?
www.gardenorganic.org.uk/schools_organic_network/leaflets/CropRotation.pdf
A 3-year rotation cycle is usually considered good enough for the home gardener.
Between seasons, plant yourself a Cover Crop, selecting them based on their advantages. Some attract those friendly Beneficial Insects like Ladybugs. Some make your Soil tilth better by injecting air, or breaking it up, or raising water-holding capacity. Turning the Cover Crop into the Soil improves structure and injects your Soil with Vitamins and other enhancements. Some build up your Soil抯 nutrient levels, others shade it to keep Weeds from sprouting or interrupting germination.
Some repel hostile insects, as I mentioned the other day. Ontario's Ministry of Agriculture explains this phenomenon to Canadian gardeners: 'Some Cover Crop species may be non-hosts for a pest or may release materials that are toxic to the targeted pest...Cover Crops like Marigolds and Pearl Millet do not support or do not allow Nematodes to reproduce. Some Mustards, particularly those with high Glucosinilate and Euricic Acid levels in the plant tissue, can create a 'natural fumigant' through the chemical breakdown of these materials.'
Rodale's 'The New Farm' website points out, 'Legume crops fix nitrogen from the atmosphere, while Grass crops create heavy root biomass. Winter Annual crops protect soil when photosynthesis is shut down or minimal, and provide strong re-growth in early Spring. Quick-germinating grains provide a nurse crop for slow-germinating perennial hay crops such as Alfalfa and Clover. These two tool sets are building blocks for regenerative farming systems... When they are used in tandem, Crop Rotations using cover crops...decrease pest pressure from insects, weeds and diseases [and] enhance biological activity in the root zone to improve nutrient transfer from Soil to plants and expand root growth.' Increasing the ratio of organic matter in your Soil does many things; one of them is that it raises the Cation Exchange Rate of your Soil, and that alone grows vegetables superior to those in Soil with a lower CE Rate. ?br>
Just a few words on Fertilizing.
Effective Organic gardening is not just 慻reen?Weed and Insect control. It also depends on use of Organic instead of Chemical fertilizers. By definition, Chemical fertilizers are Salts, destructive of microbes that promote soil health. As a scientist, you probably understand that even better than I do; I just know what I read, and study after study describes key populations wiped out from Soil just from the fertilizer that was used. Also, as Salts build up in your Soil, they get closer to damaging levels. Some crops -- Blueberries, Carrots, Green Beans and Radishes -- are not tolerant of Salts. Rome was not built in a day, but bear this in mind when using them.
You know, it might be helpful for you to become familiar with mineral molecules. Some, like Phosphorous, the root-building mineral, are famous for the insoluble complexes they form in the Soil that keep them stationed in the top layer, bound to Iron or Aluminum in Acid Soil or Calcium in Alkaline Soil, totally out of reach of roots. No matter how much you apply, it all stays locked up; plants show symptoms of deficiency.
Now let抯 talk about Japanese Beetles.
In Lawns, Japanese Beetle Grubs are one of the most ubiquitous so-called problems homeowners deal with every season. In reality, no Lawn really has a Grub Problem. Not unless the Grubs are totally out of control. Because the Soil under a Lawn is TEEMING with natural forces add odds with these larvae. The chances of a Grub growing into a Beetle are very small.
I understand however that you are dealing with the adult Beetles. And I know first ahnd how much damage a single Beetle can do to a Rosebush, a Dahlia plant, or a Vegetable Patch.
Statistically, large areas of newly disturbed soil seem to be most prone to these bugs. New homeowners go to the closing, then run home and as soon as they can they surround their new house with a new Lawn. Which quickly disintegrates as Grubs emerge in full force. There are theories about this, but I think it抯 simply a problem of the destruction, by the construction company, of the natural controls. You just don抰 run into this problem when you have an old house, an old Lawn, and a hands off homeowner whose plot hasn抰 seen a shovel or a spreader in decades. They have plenty of Grass. And they don抰 have any Grubs. So they don抰 have any Japanese Beetles.
Ditto, the Woods. The Fields. The world in general.
Left alone, your Soil is probably TEEMING with Grub predators.
What can you do about these Japanese Beetles and their root-munching offspring?
Most important: DO NOT USE GRUBKILLER.
Malathion and other broad pesticides makes the soil instantly hostile to BENEFICIAL microbes and insects. Wipe out the Beneficials and you see some real problems. Re-introduce them, and the destructive Beetles are gone.
See the websites for:
Buglogical:
http://www.buglogical.com/beneficialNematodes_control_soilDwellingPests/benefici
Suburban Habitat, a California company:
http://www.suburbanhabitat.com/pd_beneficial-nematodes.php
and Gardens Alive!, a mail order specialist
http://www.gardensalive.com/product.asp?pn=2344
These are just two of the many retailers that specialize in Good Bugs that fight Bad Bugs.
Nematodes are microscopic parasites that live off Beetle Larvae -- little C-shaped worms you probably noticed under your Grass, the size of a thumbnail. You may already know them. There a trillions of them. Some Nematodes are carriers of Bacteria that infect Grubs, make them sick and die of disease. Many control not only Beetles but a list of other pests -- Cockroaches, Fleas, and/or Termites.
Note that even HEALTHY Grass has a fair (and benign) population of Grubs. Otherwise, what would Birds eat for Breakfast? This is not a problem. Grubs have their place in the food chain. So do Beetles.
Nematodes and other beneficials are completely harmless to humans and other mammals, fish and birds. Unlike toxic Grub Killers that inflict painful collateral damage all around your house.
At my house, Beetles zero in on Roses, Hollyhocks and Strawberry leaves. But they start in the soil.
This USDA website that you asked about provides a basic overview of your Japanese Beetle problem:
http://www.forestpests.org/japbeetle/
Milky Spore Disease has been a popular treatment. It may sound like a strain of Anthrax, but MSD is a simple dried bacteria just waiting to come out of hibernation and incorporate itself into the bodies of certain insect larvae. Bacteria move from host to host in the soil under your Lawn, finding insects that dine on your Grass and flowers, leaving not a trace of toxin. Which is better for your Birds, your Butterflies, and your Ladybugs. As well as your Broccoli, your Beets and your Asparagus -- or whatever Vegetables your Japanese Beetles enjoy.
Although I have read that traditional 'Japanese Beetle Traps' supposedly attract neighborhood Beetles and cause more trouble then they fix. But in all honesty, I have never found that to be the case.
There was a study back in 2000 to identify BEST of the weapons against Japanese Beetle Grubs and the Masked Chafer, Cyclocephala hirta (a major pest in California). The study included Bacillus thuringiensis ('Bt'), Milky Spore Disease, Paenibacillus popilliae, the beneficial Nematodes Steinernema kushidai and Heterorhabditis bacteriophora. Researchers also evaluated the very strong Pesticide, Diazinon.
The winner: Steinernema kushidai, a Nematode from Japan, where they use it on golf courses.
Only Diazinon and entomopathogenic nematodes, they concluded, caused 'substantial mortality'; and S. kushidai 'activity persisted significantly longer than Diazinon.'
An abbreviated abstract is posted at the BioOne website:
http://www.bioone.org/perlserv/?request=get-document&doi=10.1603%2F0022-0493(2000)093[0071%3ABCAFWG]2.0.CO%3B2&ct=1
Cornell posts a full page on this celebrated Nematode from Japan, where it lives in the soil:
http://www.nysaes.cornell.edu/ent/biocontrol/pathogens/nematodes.html
S. kushidai is just what they doctor ordered, they say, when it comes to curing your House and Garden of all sorts of pathogenic pests. They LOVE Steinernema at Cornell, calling it 'extraordinarily lethal' for these kinds of applications, way beyond other biologic weapons. In fact, they say, 'The only insect-parasitic nematodes possessing an optimal balance of biological control attributes are entomopathogenic or insecticidal nematodes in the genera Steinernema and Heterorhabditis. These multi-cellular metazoans occupy a biocontrol middle ground between microbial pathogens and predators/parasitoids, and are invariably lumped with pathogens, presumably because of their symbiotic relationship with bacteria.'
It gets better.
'Most biologicals require days or weeks to kill, yet Nematodes, working with their symbiotic bacteria, kill insects in 24 to 48 hours.'
Nematodes classified in the Steinernema species are effective against pests ranging from Termites and Fleas to Fungus Gnats. S. kushidai specializes in 'Scarab larvae'.
Like most Nematodes, the Steinernema and Heterorhabditis Nematodes are VERY fragile fauna. Remember that if and when you acquire them. Follow directions explicitly. They can be extinguished simply by being exposed to Sunlight, or if there is insufficient Oxygen, if it is too cold or hot., or if the temperatures change too much, too soon. Dry soil will kill them. Handle with care.
Now, the bad news.
Where can you get these Steinernema and their Nematode Friends?
Ohio State posts a page listing commercial suppliers of Insect Parasitic Nematodes:
http://www.oardc.ohio-state.edu/nematodes/nematode_suppliers.htm
Not an S. kushidai in sight. Evidently this five-star Nematode is not available for sale outside of Japan yet -- or, if it is, it is part of the proprietary Nematode Zoo sold by some of the more secretive merchants. Browsing down the (somewhat outdated) list of suppliers on Ohio State's list, the most promising for your needs looks like a Canadian supplier, Natural Insect Control:
http://www.naturalinsectcontrol.com/company.html
They may be able to obtain the multitalented S. kushidai if you place a special order, or dissuade you if S. kushidai is not suitable for your purposes (due to climate for instance). Maybe if you ask about ordering Steinernema kushidai enough times, someone will send for a batch from Tokyo and start growing them here.
It may possibly be an ingredient in a proprietary Nematode Cocktail someone is selling. Meantime, start experimenting with Row Covers and some of the available predators to send the Japanese Beetles back to Japan.
And now, it is my bedtime. I just hope this does not turn into several pages of symbols and hard returns before it posts to you.
By the way, in theory, on paper, with all those Snakes and Lizards, you should not have any Slug problem. How is that going?
