I disagree... herbicide damage rarely causes spots on the leaves, and the yellowing tends to be a general overall thing (especially on the growing tips), not mottled. It's always easier to figure out with a picture, but a virus is possible. TMV is, indeed, almost nonexistent outside of labs in the US. Cucumber Mosaic Virus, on the other hand, is out there, and may be more common than you think (many Heavenly Bamboo plants carry it; the resulting red color is considered desirable). There is also Tomato Spotted Wilt Virus, which is rampant in many parts of the country. Both CMV and TSWV are vectored by insects; they are the major viruses we usually run into in tomato plants. They can strike individual plants, leaving neighbors alone. If you're dealing with an herbicide, the effects will show up on neighboring plants which are close to each other and sharing the bed, or different species of plants that share the same soil/exposure, like squash or peppers (but not necessarily every kind of vegetable). The plants might pull out of a light exposure once the source of herbicide is removed; the best sign is when they start to grow again. Badly herbicide-damaged or virus-infected plants will stop growing or slow to a crawl, and will never start again. Am I stuck with never using this soil for tomatoes again? No. Any virus you are likely to encounter in tomatoes doesn't persist in the soil. If your soil is contaminated with herbicide (and I can't imagine how you would manage that with Mel's Mix, unless the compost part was badly contaminated) then you will have to get rid of it, but not if the herbicide drifted over from elsewhere. How badly will my harvest suffer? Virus-infected plants will not bear, or will bear misshapen and often bad-tasting fruit. Since you're not likely to get any good fruit out of these plants once the virus is well established, you'll have fewer plants to harvest from. If herbicide-damaged plants recover, they will be set back by at least a few weeks, but the fruit you get after that should be fine. Is moving the plants to a different part of my back yard sufficient, or do I need to destroy them? If it's a virus, you need to pull them. CMV and TSWV are transmitted by insects which can fly, and infected plants can serve as a reservoir for insects to infect your currently healthy plants. (Besides, they won't fruit well, so why keep them?) If it's herbicide damage... well, if the soil isn't the problem, and there's no new drift from elsewhere, then there's no real point to moving them. Either they'll pull out or they won't. How likely is it that all my tomato plants are infected? I have around a dozen plants and hate to think that I need to destroy them all. I've gotten a few virus-infected plants over the years; once I confirm that it's a virus rather than some quirk of weather or genetics, I pull the (usually single) plant and look for the same symptoms on other plants. Out of three years I've had a virus problem, I've had to pull four plants total, and I grow over 15 plants a year. So keep your eyes peeled, and if you're lucky, it might turn out to be just a couple. They're all growing well. Now this is what confuses me. Is it just the normal-looking plants that are growing well? If so, cross your fingers and leave them be. If the shoestring-leaf ferny plants are also growing "well", as in vigorous and putting out lots of new growth, digdirt may be onto something with his herbicide theory. Here's a few pics to help out: Cucumber Mosaic Virus Tomato Spotted Wilt Virus --Alison

If you are interested and willing to search (Google or Bing), check out some of the articles on AGDIA, which is a company that makes tests for viruses and other diseases of plants. You can see the PCR and ELISA tests that are available for roses (and for many other plants.) Do you know the word "Synergy"? Not the new age version, but the science based synergy- there are some interesting plant pathology sites out there as well. Briefly, Synergy means that diseaseA has X symptoms and disease B has Y symptoms, but when a plant has diseases A&B, the plant will not have a simple mix of X and Y symptoms, but often will also have new (call them Z) symptoms that may be worse that the sum of X and Y. Where does that leave rose growers? It leaves rose growers wanting to keep their plants as healthy as possible so that no even more damaging symptoms appear. Years ago a simple study was done in California roses. Under optimum conditions, roses with a single virus (as tested for back then) produced ten to fifteen per cent fewer blooms. That, economically, was reason to keep the plants as clean as possible. And to the root to root transmission: Google Scholar papers by Giolino (author), roses, and the time period last ten years.

Mosaic virus is rarely, if ever, fatal,in its self. It can weaken plants,so that they are attacked by other pathogens.The plants also can become such poor perfomers that they will be discarded. Some varieties have much more resistance than others,and will grow and bloom quite well,while the insects transfer the disease from it to other plants.The other plants may not do so well. GW owns posted poctures, so I have them elswhere. They also won't allow url links to the site or mention of competitors. If you input Mosaic virus , TMV or Hippeastrum Mosaic virus to a search engine,there is much tu be learned. Del

Yes, they do mention the symptoms and have pictures. "Field observations showed that PPSMV-2-infected plants of different cultivars consistently exhibited mosaic (Fig. 4a) and stunting, and, in a single case, sterility, whereas chlorotic ringspots and line patterns of the leaves, but no apparent decrease in vigour, were shown by PPSMV-1-infected plants (Fig. 4b). When both viruses were present in the same plant, these plants displayed more-severe symptoms, i.e., chlorosis, leaf deformation, mosaic and sterility typical of SMD (Fig. 4c and d)." --------------------------------------------------- Regarding mite spread: "Successful ‘‘stapling transmission’’ experiments confirmed the efficacy of this technique for transferring PPSMV-1 and PPSMV-2 to healthy test plants (pigeonpea and French bean) by A. cajani under greenhouse conditions. However, it remains to be established if transmission occurs with a different efficiency for each virus or if other eriophyid mites have a role in their spread in nature."