Onion Root Knot Nematode Management: How To Treat Root Knot Nematodes On Onions

Root Knot Nematode Of Onion Plants – Controlling Onion Root Knot Nematodes

Root knot nematode of onion is a pest that can drastically reduce the yield you get from your row of onions in any given year in the garden. They feed on the roots and cause plants to stunt and develop fewer, smaller bulbs. There are both chemical and non-chemical management practices you can use to reduce losses.

Signs of Root Knot Nematodes on Onions

Nematodes are microscopic roundworms that live in the soil, most of which do not damage plants. The root knot nematode is not one of those roundworms. It lives in the roots of a host plant, and there are four species that affect onions. They are able to infect onion roots when temperatures in the soil are over 41 degrees Fahrenheit (5 degrees Celsius).

Above the soil, what you’ll see in root knot nematode of onion infections is uneven growth and stunted plants. The necks of bulbs will be thicker and the bulbs themselves smaller. The plants will mature later during an infection. The leaves may also yellow.

Underground, the roots will develop galls, swollen and enlarged areas of the roots. Root growth will be stunted, and you’ll see shorter roots than is normal.

Onion Root Knot Nematode Management

Controlling onion root knot nematodes starts with prevention. There are no resistant onion varieties, but you can use plants or seeds that are clean and nematode free. This doesn’t, however, mean you won’t get an infestation because the nematodes may already be in your soil.

If you know that your soil is infested with this pest, you can use a pre-planting fungicide to fumigate the soil and reduce or eliminate root knot nematodes. This is generally considered to be an effective management strategy and is used in commercial onion growing.

To avoid fungicides, you can try crop rotation or cover crops. Rotate in crops that do not host root knot nematodes, like grains and corn, or grow them as cover between onion plants.

While using fungicide is the most effective way to manage onion root knot nematodes, using the non-chemical cultural practices of crop rotation and cover crops will reduce losses. These are worth trying if you don’t want to use chemicals in your garden.


Onion Spacing: Tips and Tricks

Onions should be spaced 2 to 4 inches apart, with 12 to 18 inches between rows. Onion seeds can be sown close together, and thinned out once the seedlings have grown. Sets, or small immature onions, should be spaced like onion plants.

Green onions are the exception and can be planted one inch apart. It is a good idea to spread onions out around your garden instead of confining them to one spot. Onions can deter pests with their scent, so spreading them out can help protect your other veggies as well.

The way you space your onions depends on how you start them. Spacing for seeds is very different from spacing for onion sets or even more established onion plants.

If you are using one large container for your seeds, sprinkle them evenly over compost. Then cover the seeds with another, lighter layer of compost and water. This is one of the easiest ways to start onion seeds.

Instead of using a single container or pot, some gardeners choose to use a partitioned container. Individual cells keep the onion seedlings separate and lets you skip the sometimes tricky process of pulling apart seedlings that may have intertwined roots.

In a partitioned container, you should still plant at least a couple seeds in each cell in case one of the seeds doesn’t germinate. It is unlikely that you will have a 100 percent germination rate, and it would end up being a waste of space and time to find that half of the seeds in your cells have not germinated.

With seeds, remember to sow liberally. Once the seedlings have sprouted, you can pick and choose from the ones that are healthiest and have the best chance of producing a good crop.

Spacing for Onion Sets

Onion sets are small bulbs of immature onions. They are harvested specifically for the purpose of growing more onions. As they are a great deal bigger than seeds, they require more space.

As with seeds, you can use a partitioned container and plant one set per cell. This method makes for an extremely easy transplant once your sets have sprouted and developed some growth.

Sets are less difficult to separate than young plants grown from seed, so planting all of your sets in one large container or area won’t give you much difficulty when it comes time to transplant. You can also plant them directly into your garden.


How to Plant and Grow Garlic (Allium Sativum)

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A close relative of the onion, garlic (Allium sativum) is an edible, bulbous plant that has been cultivated for several thousand years. It is more popular today than ever and, with over 600 sub-varieties available, there is ample room for gourmet garlic growers to carve out a niche. For the home gardener, it is quite easy to grow a year’s supply, and the leftover crop can be given away to friends and neighbors.


The many sub-varieties of garlic fall into two basic categories: hardneck garlic (Allium sativum var. ophioscorodon), which includes the varieties porcelain garlic, rocambole garlic, and purple stripe garlic. The softneck garlic (Allium satvum var. sativum) varieties include artichoke garlic, silverskin garlic, and creole garlic.

Softneck varieties are best for warm climates, while hardneck is the garlic of choice for northern garlic growers. Softneck garlic stores and travels better than hardneck garlic. It also has a stronger flavor and generally speaking, produces larger cloves. If you want a milder garlic taste, try elephant garlic—which is actually more closely related to leeks than it is to true garlic.

Planting and Growing Tips

Garlic is planted either in the fall or the spring, depending on your climate. In the north, plant garlic in the fall. In warmer climates, it is best to plant garlic in early spring, though seed garlic must be chilled first to break it out of its dormant state. Garlic prefers loose loamy soil with plenty of organic matter.

  1. Separate the bulbs into individual cloves right before planting, leaving the papery layer around each clove. Choose larger cloves for planting and use the little ones for eating or preserving.
  2. Plant the cloves 2 inches deep if you plan to mulch and 3 to 4 inches deep if you do not plan to mulch.
  3. Be sure to plant each clove with the pointy tip facing up and the basal/root end facing down.
  4. Space the cloves 4 to 6 inches apart in rows spaced 18 to 24 inches apart. Commercial growers often plant the cloves and rows closer together; this leads to smaller bulbs but an overall higher yield in terms of garlic per square foot of garden.

Soil and Mulch

Soil should be kept evenly moist through the first part of the growing season, but allow the soil to go dry for two or three weeks before harvest time. If conditions are too wet near harvest time, mold may grow.

Mulching your garlic with straw, hay, swamp grass, reeds, or chopped leaves or plastic can be very helpful in some circumstances, though it is not recommended in wet climates. Mulch can protect against winter kill in cold climates, and in hot climates, It helps moderate soil temperatures and conserves soil moisture.

Good mulch can also help keep weeds in check. Weeds can easily outcompete young garlic plants, so be sure to keep the plot well-weeded.

Pests and Problems

Extreme temperatures can damage your garlic crop. Other problems include:

  • White rot fungus: This disease, caused by the Sclerotium cepivorum fungus, is the most serious disease of garlic, and it can also strike all Allium crops, including onions. White rot-infected garlic plants can be identified by leaves that turn yellow and plants that wilt and die back partially. As the roots rot, infected plants uproot easily. This disease typically develops from the middle of the season up to harvest. Be sure you obtain cloves from certified disease-free stock because once a field has been infected with white-rot fungus, it can take decades for the infection to completely clear.
  • Nematodes: These microscopic pests, Ditylenchus dipaci, are another chronic problem for garlic. These tiny worm-like creatures live inside the garlic plant itself, eating it as it reproduces. Nematodes do not need water to survive and they can live in the surrounding soil for several years. Nematode infestation can build up for several seasons without much damage, then strike and take out an entire crop. To control nematodes, make efforts to plant clean stock, inspect growing plants frequently, and remove any plants that look diseased.
  • Onion thrips: Thrips are the most common insect to plague garlic. Thrips have rasping-sucking mouth parts that first damage the leaves then suck up the seeping plant fluid. Severe damage can cause the garlic plant to wilt and die. The wounds to the leaves may then create entry points for other diseases. To control thrips, keep areas free of moist, wet mulch that provides breeding areas, and trap the insects with sticky traps.


As it grows, hardneck garlic produces a curly green flower stalk called a scape. Garlic scapes should be harvested from the plant as it grows so that the garlic concentrates its energy into growing the bulb larger.

It’s time to harvest your garlic when 1/2 to 3/4 of the bottom leaves have died. This usually happens by mid- to late-summer—July and August for most areas. Harvest a test bulb or two to determine maturity. The garlic bulb should be well-wrapped but not split. To harvest garlic, loosen the soil with a shovel or fork and pull up plants by hand. Use caution, as garlic bruises easily.

Storage and Preservation

You can eat garlic fresh out of the ground, but if you want to store it for winter, you must cure it first. In warm sunny climates, garlic can be left in the field to dry, but it should be covered with leaves to prevent sunburn.

Place garlic in a dark place with good air circulation for 2 to 3 weeks after harvest to allow it to cure.

  • For softneck garlic, you can braid ropes of bulbs and stems and hang them to dry.
  • For hardneck garlic, trim stems to one inch above the bulb then place in a dark, well-ventilated place.

After curing, garlic will keep at for 6 to 12 months when stored in optimal conditions. Store garlic where it will have good air circulation, 65 to 70 percent humidity, and a temperature of 35 to 50 degrees Fahrenheit.


Garlic is propagated by planting individual cloves separated from bulbs or by using bulbils—the tiny undivided bulbs found in the scapes of hardneck garlic. Propagating garlic using bulbils can be much more effective than planting cloves. If you are planting cloves, save 15 to 20 percent of your crop, making sure to use only truly disease-free bulbs for planting next season.

There are many more bulbils than cloves, making it easier to build up your planting stock, and since bulbils are above the ground, there is less chance of soil-borne diseases. Plant them just like you would cloves. If you are growing bulbils for seed, allow the garlic scape to grow—they are edible and delicious.


Root Knot Nematode Control : Saving Carrots Affected By Root Knot Nematodes

Garden diseases are the bane of any gardener, especially when they threaten our food crops. Root knot nematodes in carrots are a major pathogen which also affects other food crops, such as onions and lettuce. Carrots affected by root knot nematodes display malformed, stubby, hairy roots. The carrots are still edible, but they are ugly and distorted with tough galls and thick skin. Additionally, root knot nematodes reduce yield. Root knot nematode control is possible through several corrective measures.

Carrot Root Knot Nematode Info?

If you have discovered your carrot patch is yielding stumpy, rough looking, forked roots, you probably have a root knot nematode infestation. This pathogen is common in root crops but also in celery and lettuce. Symptoms vary slightly by plant variety, but in all cases crop production is reduced and the food looks unsightly. Root knot nematodes in carrots are particularly prevalent in northern regions. The good news is that you can control the pathogen to a certain extent.

Nematodes are tiny roundworms not visible with the naked eye. It takes a soil sample to positively identify the pests. They live in soil and feed on plant cells through several developing stages. The second stage juveniles are the only mobile stage and enter the roots. Later stages and adults become larger as the carrot root enlarges.

Any stage of nematode feeds on cells by piercing it with a mouthpart called a stylet. Females will break through the root and deposit eggs, which form galls. These become woody, hard and nearly unpalatable. There are almost 90 different nematode species that are directly associated with carrot development.

Symptoms of Carrot Root Knot Nematodes

Recognizing parasitic nematodes in carrots is fairly obvious once you dig the roots up. On the surface of the soil, the foliage will be stubby and not well formed. Occasionally, it will also wilt. The roots will split and fork, looking like bizarre caricatures of possessed carrots. Some interesting forms appear but, overall, carrots affected by root knot nematodes will produce less edible roots, which are stunted and ugly.

In commercial growing, this represents less dollar yield and the roots collect more soil, requiring more extensive cleaning before the roots can be marketed. In the home garden, the less attractive roots can still be used, but some parts will be woody and preparation is more intense as opposed to the easily cleaned and peeled roots that are uninfected.

Root Knot Nematode Control

The most common treatments are crop rotation and allowing a field to lay fallow. Good sanitation practices such as cleaning machinery and tools is also useful. In some cases, solarization for 4 to 6 weeks can kill populations of some nematodes.

There are also several resistant crops that may be planted or a non-host plant can be installed. Such plants might be rye, fescue, corn, wheat, barley or sorghum. At this time, there are no resistant carrot varieties, but trials are underway and very soon these should be released.

There are a few soil fumigants that can be used up to 6 weeks before planting. They can be quite effective when used properly.


How to Manage Pests

Pests in Gardens and Landscapes


In this Guideline:

Nematodes are microscopic, eel-like roundworms. The most troublesome species in the garden are those that live and feed within plant roots most of their lives and those that live freely in the soil and feed on plant roots.

Although California has many different species of root-feeding nematodes, the most damaging ones to gardens are the root knot nematodes, Meloidogyne species. Root knot nematodes attack a wide range of plants, including many common vegetables, fruit trees, and ornamentals. They are difficult to control, and they can spread easily from garden to garden in soil on tools and boots or on infested plants.

A number of other nematode species also can damage home garden and landscape plants including the ring nematode (Criconemoides xenoplax), root lesion nematodes (Pratylenchus species), the sugarbeet cyst nematode (Heterodera schachtii), the citrus nematode (Tylenchulus semipenetrans), the stem and bulb nematode (Ditylenchus dipsaci), and others. Tables 1, 2, and 3 list some common garden plant species and their nematode pests.


Plant-feeding nematodes go through 6 stages—an egg stage, 4 immature stages, and an adult stage. Many species can develop from egg to egg-laying adult in as little as 21 to 28 days during warm summer months. Immature stages and adult males are long, slender worms. Mature adult females of some species such as root knot nematode change to a swollen, pearlike shape, whereas females of other species such as lesion nematode remain slender worms. Nematodes are too small to be seen without a microscope.

It is believed the root knot nematode survives from season to season primarily as eggs in the soil. After the eggs hatch, the second-stage juveniles invade roots, usually at root tips, causing some of the root cells to enlarge where the nematodes feed and develop. The male nematodes eventually leave the roots, but the females remain embedded, laying their eggs into a jellylike mass that extends through the root surface and into the soil.


Root knot nematodes usually cause distinctive swellings, called galls, on the roots of affected plants. Infestations of these nematodes are fairly easy to recognize; dig up a few plants with symptoms (see below), wash or gently tap the soil from the roots, and examine the roots for galls. The nematodes feed and develop within the galls, which can grow as large as 1 inch in diameter on some plants but usually are much smaller.

The formation of these galls damages the water- and nutrient-conducting abilities of the roots. Galls can crack or split open, especially on the roots of vegetable plants, allowing the entry of soil-borne, disease-causing microorganisms. Root knot nematode galls are true swellings and can’t be rubbed off the roots as can the beneficial, nitrogen-fixing nodules on the roots of legumes. Root knot nematodes can feed on the roots of grasses and certain legumes without causing galling.

Aboveground symptoms of a root knot nematode infestation include wilting during the hottest part of the day even with adequate soil moisture, loss of vigor, yellowing leaves, and other symptoms similar to a lack of water or nutrients. Infested vegetable plants grow more slowly than neighboring, healthy plants, beginning in early to midseason. Plants produce fewer and smaller leaves and fruits, and ones heavily infested early in the season can die. Damage is most serious in warm, irrigated, sandy soils.

Root injury from other nematode species can produce aboveground symptoms similar to those from root knot nematodes. However, the actual injury to the roots is more difficult to detect. Roots can be shortened or deformed with no other clues as to the source of the injury. You can confirm a nematode infestation by collecting soil and root samples and sending the material to a laboratory for positive identification of the infesting species.

Although nematodes can kill annual plants, they rarely kill woody plants. Nematode injury to woody plants usually is less obvious and often more difficult to diagnose. Infested fruit and nut trees can have reduced growth and yields. Woody landscape plants that are heavily infested can have reduced growth and branch tip dieback and can defoliate earlier than normal.

Detecting Nematodes in Soil Samples
Table 1. Landscape Plants Known or Suspected of Being Damaged by Nematodes in California.

1 Most varieties susceptible to at least one species of the nematode type listed.

Nematodes are too small to see without a microscope. Often you become aware of a nematode problem by finding galled roots on a previous crop. However, you also can use a simple bioassay to detect root knot nematodes in garden soil. Melons seeded in pots in moist soil collected from the garden will develop visible galls on the roots in about 3 weeks when pots are kept at about 80ºF if root knot nematodes are present. As a comparison, melons planted in heat-sterilized soil won’t develop galls.


Management of nematodes is difficult. The most reliable practices are preventive, including sanitation and choice of plant varieties. You can reduce existing infestations through fallowing, crop rotation, and soil solarization. However, these methods reduce nematodes primarily in the top foot or so of the soil, so they are effective only for about a year. They are suitable primarily for annual plants or to help young woody plants establish. Once nematodes infest an area or crop, try to minimize damage by adjusting planting dates to cooler times of the season when nematodes are less active. Try to provide optimal conditions for plant growth including sufficient irrigation and soil amendments to make plants more tolerant to nematode infestation.


Nematodes usually are introduced into new areas with infested soil or plants. Prevent nematodes from entering your garden by using only nematode-free plants purchased from reliable nurseries. To prevent the spread of nematodes, avoid moving plants and soil from infested parts of the garden. Don’t allow irrigation water from around infested plants to run off, as this also spreads nematodes. Nematodes can be present in soil attached to tools and equipment used elsewhere, so clean tools thoroughly before using them in your garden.

Resistant or Tolerant Varieties and Rootstocks

One of the best ways to manage nematodes is to use vegetable varieties and fruit tree rootstocks that are resistant to nematode injury. Tomato varieties with the code VFN (Verticillium, Fusarium, Nematodes) on the seed packet or label are resistant to common root knot nematode species. Although even resistant tomato varieties can still exhibit some root galling under high nematode levels, they usually maintain their yield. For example in recent vegetable garden-type experiments on root knot nematode soil, nematode-resistant tomatoes yielded almost 6 times more tomatoes than a similar susceptible variety. An additional benefit of growing a resistant variety is the nematode levels in the soil decline rather than increase, making it more feasible to grow a susceptible crop the following season.

Host plant Nematode(s) 1
albezia root knot
alder root knot
azalea stunt
boxwood root knot
cactus root knot, cyst
catalpa root knot
cedar root knot, pinewood
euonymus root knot
fir dagger
ginkgo root knot
hibiscus root knot
hydrangea root knot
juniper root knot
larch pinewood
lilac citrus
mulberry root knot
oak root knot
palm root knot
pine pinewood
pittosporum root knot
poinsettia root knot
rose root knot, root lesion
spruce pinewood
tamarisk root knot
Table 2. Fruits and Nuts Known or Suspected of Being Damaged by Nematodes in California.

1 Most varieties susceptible to at least one species of the nematode type listed.
2 Harmony and Freedom grape rootstocks are resistant to root knot nematodes.
3 Nemaguard and Nemared (peach) rootstocks are resistant to root knot nematodes.
4 Royal Blenheim rootstock is resistant to root knot and root lesion nematodes.

For fruit trees and vines, Nemaguard rootstock used for stone fruit and almond trees and Harmony and Freedom rootstock used for grapes provide protection against root knot and other nematodes. Citrus trees growing on Troyer and Trifoliate rootstocks are resistant to the citrus nematode. Consider replacing severely infested plants with plant species and varieties that are more tolerant of the nematodes present. Unfortunately, resistant varieties aren’t available for many crops and ornamentals.

Fallowing and Rotation

Growing a crop on which the nematode pest can’t reproduce is a good way to control some nematodes. For example, the sugarbeet cyst nematode attacks only a limited number of crops including cole crops (broccoli, Brussels sprouts, cabbage, and cauliflower) and related crops and weeds. Growing nonsusceptible crops for 3 to 5 years reduces the sugarbeet cyst nematode population to a level where you can grow susceptible crops again. Unfortunately, rotation isn’t as easy for controlling root knot nematodes, because so many vegetable crops and weeds are hosts of the pest.

However, with careful planning, rotation in combination with fallowing and solarization can reduce root knot nematode numbers. Annual crops that are useful in a rotation plan for reducing root knot nematode populations include small grains such as wheat and barley, sudangrass, and resistant tomato and bean varieties.

Fallowing is the practice of leaving the soil bare for a period of time. Fallowing for 1 year will lower root knot nematode populations enough to successfully grow a susceptible annual crop. Two fallow years will lower nematode numbers even further. When fallowing, it is important to keep the soil moist to induce egg hatch and to control weeds on which nematodes can survive. As a result, eggs will hatch, but the nematodes will die if there is nothing to feed on.

You will need to repeat fallowing when you begin to see root injury again, as nematodes can build up to damaging levels even in a single season. A good way to conduct a fallowing program is to split the garden into thirds and fallow one-third every year or two on a rotating basis. If you intend to grow woody plants in a nematode-infested area, consider fallowing the soil for 4 years before planting. Table 4 gives an example of a rotation/fallowing plan that would be useful for root knot nematode control.

Soil Solarization
Host plant Nematode(s) 1
Grapes and small fruits
grape root knot 2 , root lesion, ring, citrus, dagger, stubby root
blackberry, raspberry root lesion, dagger
strawberry root knot, root lesion, foliar
Fruit and nut trees
almond root knot 3 , root lesion, ring
apple root knot, root lesion
apricot root knot 4 , root lesion 4 , ring
avocado root lesion
cherry root lesion
citrus root lesion, citrus
olive root lesion, citrus
peach, nectarine root knot 3 , root lesion, ring
pear root lesion
plum, prune root lesion, ring, pin
walnut root knot, root lesion
Table 3. Vegetables Known or Suspected of Being Damaged by Nematodes in California.

1 Most varieties susceptible to at least one species of the nematode type listed.
2 Some blackeye, lima, and snap bean varieties are resistant to Meloidogyne incognita, a species of root knot nematode.
3 Tomato varieties designated “N” are resistant to most root knot nematode species.

You can use solarization to temporarily reduce nematode populations in the top 12 inches of soil, which allows the production of shallow-rooted annual crops and helps young woody plants become established before nematode populations increase. However, solarization won’t provide long-term protection for fruit trees, vines, and woody ornamental plants.

For effective solarization, moisten the soil, then cover it with a clear, plastic tarp. Leave the tarp in place for 4 to 6 weeks during the hottest part of summer. Root knot nematodes, including eggs, die when soil temperature exceeds 125°F for 30 minutes or 130°F for 5 minutes. The effectiveness of solarization is reduced in cool coastal areas, where summer temperatures commonly remain below 80°F. For a complete discussion of solarization, see Soil Solarization listed in References.

Planting and Harvesting Dates

Most nematode species are active during warm summer months and can’t penetrate roots at soil temperatures below 64°F. Therefore, you can reduce nematode injury to fall-planted crops such as carrots, lettuce, spinach, and peas by waiting until soil temperatures have dropped below 64°F. Plant summer vegetables as early as possible in spring before nematodes become active. Plants with larger root systems, even though nematode-infested, might be able to remain productive longer. It is also helpful to remove annual vegetables, including their roots, as soon as harvest is over, to prevent nematodes from feeding and breeding on root systems.

Nematode-suppressive Plants

Certain marigolds, Tagetes species, suppress root knot and lesion nematodes. French marigolds (varieties include Nemagold, Petite Blanc, Queen Sophia, and Tangerine) are most effective. Avoid signet marigolds, T. signata or tenuifolia, because nematodes will feed and reproduce on these. Marigolds don’t work well against the northern root knot nematode, Meloidogyne hapla, a species common in areas with cool winters. The effect of marigolds is greatest when you grow them as a solid planting for an entire season. When grown along with annual vegetables or beneath trees or vines (intercropping), nematode control usually isn’t very good. To prevent marigold seed from getting in the soil, cut or mow the plants before the flowers open. As with other cultural control methods, nematode populations rapidly will increase as soon as you grow susceptible crops again.

Soil Amendments and Irrigation

You can add various organic amendments to the soil to reduce the effect of nematodes on crop plants. The amendments—which include peat, manure, and composts—are useful for increasing the water- and nutrient-holding capacity of the soil, especially sandy soils. Because nematodes more readily damage plants that are water-stressed, increasing the soil’s capacity to hold water can lessen the effects of nematode injury. Likewise, more frequent irrigation can help reduce nematode damage. In either case, you will have just as many nematodes in the soil, but they will cause less damage.


Currently no chemical nematicides or soil fumigants are available to home gardeners for nematode control in backyard gardens and home landscapes.

Host plant Nematode(s) 1
beans root knot 2 , root lesion
beets root knot, cyst
carrots root knot
celery root knot
cole crops root knot, cyst
corn root lesion
cucumbers root knot
eggplant root knot
garlic stem and bulb
lettuce root knot
melons root knot
onions stem and bulb
peas root knot, root lesion, cyst
peppers root knot
potatoes (Irish) root knot, root lesion
potatoes (sweet) root knot
radish root knot, cyst
spinach root knot, cyst
squash root knot
tomatoes root knot 3
turnips root knot, cyst
Table 4. Example of a Rotation Plan for a Root Knot Nematode-infested Garden 1 .

1 Garden is divided into three sections: A, B, and C.


Dreistadt, S. H., J. K. Clark, and M. L. Flint. 2004. Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide. Oakland: Univ. Calif. Agric. Nat. Res. Publ. 3359.

Elmore, C. L., J. J. Stapleton, C. E. Bell, and J. E. DeVay. 1997. Soil Solarization: A Nonpesticidal Method for Controlling Diseases, Nematodes and Weeds. Oakland: Univ. Calif. Agric. Nat. Res. Publ. 21377.


Pest Notes: Nematodes

UC ANR Publication 7489

Authors: E. J. Perry, UC Cooperative Extension, Stanislaus Co.; and A. T. Ploeg, Nematology, UC Riverside.

Produced by University of California Statewide IPM Program

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Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2019 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

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First winter First summer Second winter Second summer Third winter Third summer
Section A fallow fallow fallow plant summer-susceptible crop plant winter/spring crop plant summer-resistant crop
Section B plant winter/spring crop summer solarize plant winter/spring crop plant summer-susceptible crop fallow summer solarize
Section C plant winter/spring crop amend soil, plant summer-susceptible crop fallow fallow fallow fallow or plant summer-resistant crop