Well, since I have already discussed the "NAPALM" chemical aka temik for control of nematodes, I figured that I would now thing of more natural way of controlling RKN in pot culture.

I just started playing with Neem oil for control of fungus gnats. MAN, I hate those things. I have probabbly lost about 100 cuttings so far to those &**&^^ things. Well, after reading Dr Taplas musings/comments on Neem, I wondered if it can be used for RKN.

It seems neem oil does have an effect on RKN. I know some of have trees in pots that we are going to pitch due to RKN; I know 4 trees I just found that have RKN, which were purchased at a local nursery. Well, I my just have to try a drench, root dip, and any other ideas? (The heat treatment works great.) Can you imagine saving a tree from RKN? Any who, just thought I would let some of the great minds on the forum, mull this over.

Here is what I have found:

http://www.nap.edu/openbook.php?record_id=1924&page=51

Effects on Other Organisms

Although neem's effects on pestiferous insects are by far the best known, the tree's various products can influence other pest organisms as well. In the long run, these may well prove the most important of all. At present, however, the effects on noninsect pests are poorly understood. This chapter highlights some of the findings to date.

NEMATODES

Neem products affect various types of nematodes. This may be significant because certain of these thread worms are among the most devastating agricultural pests and are also among the most difficult to control. In addition, an increasing number of synthetic nematocides have had to be withdrawn from the market for toxicological reasons.

Today, there is a small but increasing body of evidence that neem might provide useful replacements. Certain limonoid fractions extracted from neem kernels are proving active against root-knot nematodes, the type most devastating to plants. They inhibit the larvae from emerging and the eggs from hatching, and in at least one test they have done so at concentrations in the parts-per-million range.1 Water extracts of neem cake (the residue remaining after the oil has been pressed out of the seeds) are also nematocidal.

In a careful trial in Aligarh, India, amending soil with sawdust and neem cake dropped the root-knot index to zero and, of all the treatments tested, gave the greatest growth of tomatoes, a crop that is very sensitive to these nematodes.

In tests in a greenhouse and in the field in Germany, tomato plants were obviously improved by neem products, but there was no significant difference in the numbers of some nematode species in the soil. However, among treated and untreated soils the majority was extracted from the roots of plants in untreated soil.2

Here is the other link:

http://www.neemoilpesticide.com/nematodes.html

Here is the google search:

http://www.google.com/search?hl=en&q=neem+oil+nematodes&btnG=Google+Search&aq=o&oq=

And another link to a google book:

http://books.google.com/books?id=q38W9fSoHTwC&pg=PA309&lpg=PA309&dq=neem+oil+nematodes&source=web&ots=sXFttZPnOI&sig=l-7waY_wGhfSh60pVFWf-z0aLwk&hl=en&ei=LHeWSYhuneCwA-ioyYoB&sa=X&oi=book_result&resnum=2&ct=result

Whew, I am tired. Good night!