root knot nematodes

I've been told that I can minmize this problem if I have a 'heavier' soil. That much I can do. Years ago there was a soil treatment called vapam that you could use to kill virtually everything that was in the dirt. It has since been taken off the market, banned by the USDA, I believe.
In my garden, which is mostly sand, I've got this problem. They attack the roots of my tomatos, okra, squash, carrots, beans. The only thing they don't mess with are strawberries, green onions and flowers.
Are there any soil treatments out there, especially natural ones, that do a good job on nematodes?

You should be able to do solarizing where you live, no problem - that kills almost anything if it's done right. This is the best time of year to do it, too.

http://www.aces.edu/pubs/docs/A/ANR-0713/

clay
Excellent link. I knew about that many years ago, but had managed to forget. Since I only have 3 or 4 good brain cells remaining, that would explain my memory.
I've got alot of 6mil black plastic sheeting, and I will try that, even though the link advises using clear plastic. Wonder why? Seems like black plastic would transmit higher soil temps than clear.
After solarizing, I'll add plenty of composted cow manure as well. That should help.

There have been other threads about this - I think it was tapla who used the analogy of sitting in a car with tinted windows versus clear. The clear plastic will let more light and therefore heat into the soil. The heat and light on black plastic won't transfer down into the soil, it goes up where it doesn't help.

That being said, I have used black rubber roofing membrane for this, but I guess it's really not solarizing, since it's opaque and doesn't let light through. But it's very thick and heavy so it lays in close contact with the soil, more than polyethylene would. I was just trying to get a head start on killing grass and weeds... it probably wouldn't kill seeds and pathogens like true solarizing does, though.

clay,
You are probably correct. I have found that I have a few square yards of clear plastic that I have saved from other sources -- ie.-the clear plastic bag that my latest mattress purchase came in. Might as well use it, haven't found any other use for it so far.

I wonder, though, if solarizing will be enough? If I remember correctly (I used solarization to kill Bermuda grass in Phoenix) it only penetrates the top 3-4" of soil, so depending on how far down the nematodes go, it might be only a setback to them. I wonder if there's any other defenses, like beneficial nematodes? Or maybe solarization done twice, the second time after tilling?

Good luck!

This is from the link above:

Claypa, your re-iteration is well noted. But Pagan does offer a valuable question. Just how deep into the dirt does solarization actually penetrate? Isn't it just the overwhelming heat that does the job relatively close to the surface?
For many garden crops the avail, or needed depth of the dirt can easily be 12" or deeper. Will solarization work that deep?

LOL - sorry, I didn't go all the way through your link.

And I think it's worth noting, too, that in other cases solarization might not be as effective because of the initial soil temps and available sunlight - the link is from Alabama, which is considerably warmer in parts than my part of the country. But for you, blmlb, it should be reasonably close, or even better.

I don't know how necessary your plot is for production. It appears if you can let it sit, weed free, for a summer that it helps decrease the population. I'm also seeing references to close plantings of French marigolds (this is from an Australian site):
"Most varieties of French marigold (Tagetes patula), especially Petite Harmony and Petite Yellow, are resistant to root-knot nematode because their roots secrete nematicidal chemicals. This phenomenon can be utilised for nematode control by dividing a vegetable garden into strips or blocks and planting marigolds in some part of the garden each year. Since a complete cover of marigolds is required, seed or seedlings should be planted no more than 15 cm apart and weeds should be kept under control until the marigold canopy crowds out competing weeds. After flowering, seed-bearing heads are removed to provide seed for the following crop and to reduce annoying volunteers that will be weeds in the succeeding vegetable crop. The marigolds are then incorporated into the soil with a spade or rotary hoe."

... and the planting of nematode resistant crops:
"possible to grow crops of sweet corn, strawberry, capsicum, cabbage or cauliflower, as these crops tend to be resistant or tolerant to some species of root-knot nematode..."


Hope this helps!

One of the best natural ways to suppress and actually control Root Knot Nematode is to keep a high level of organic material in the soil. This organic matter (if it's good) will provide beneficial bacteria that will actiully attack these nematodes. The nematodes will also feed on the organic matter and not disturbe the plants to a point. There are also Yucca Shidgera based products that will kill nematodes and there is one Organic Fertilizer that will reduce the problem about 50-70% the first year and up to 100% by the second year. Contact me offline for more detail about the fert. I don't know if I'm allowed to mention it here.

Absolutely, especially if it works!

claypa,
unfortunately, or fontunately, since my company sells one of these products, we are not allowed to self promote. I can tell you this much, I am an Agronomist and was a Grower and Grower supervisor for 25 years in 9 different countries and managed fruit and vegetable growing operations, some as large as 20,000 acres, both conventional and Certified organic, and this is the best alternative I have seen.