Hi, a few things would be helpful to know.

How old are the plants. Since sprouting and final transplant?

Describe plant size and general vigor as well as weather.

Did you get rid of the aphids?

Are you experiencing blossom drop or are they not blooming?

An anti fungal is good for me to use. Can't say for your area.

There is a set spray but wiser than me advise against it.

Is that enough water?

Reading the FAQ is a good thing.

I could be wrong, but I doubt Daconil would have anything to do with fertilization. My tomatoes have early blight (a disease) and that's what was recommended to me for it.

Do you notice bees around your tomatoes? You might have to start hand fertilizing, which I'm sure you can find tons of info on here.

Dave,

The aphids are gone. We got tons of rain on the east coast in June, perhaps the most in history, perhaps keeping the pollen from spreading.

The water I'm told, is plenty, for I'm soaking 8 foot deep in the trench.

The plants were bought from TomatoBabyCompany in Tennessee, and selectedplants in Alabama and were quite big when I got them. I did notice aphids on the ones from Tennessee when I got them, but otherwise they were vigorous and fantastic, and I transplanted them in early May.

The plants that have fruited are at least four feet tall, but the ones that haven't mostly are between 18 inches and 3 feet, and some have curled leaves, some look atrophied, some look very healthy but with no fruit. I have pruned all of them for the first six inches or so in order to have no leaves on ground.

I experienced only one blossom rot on the Black Krim, but the other Krims are doing well, though green.

Sungold is an absolute champ...it almost appears artificial compared to the others. Marianna's Peace and Anna Russian are doing well, too. None of the plum tomatoes are showing fruit, and I have perhaps five varieties, one which is Opalka, and its almost four foot tall.

Other will have to help. I've grown none of those you listed.
I'd manually check moisture with my fingers a few inches down from the surface, inside of the drip ring of each plant, noticing any difference between the runts and the larger plants.

Blossom drop or lack of blooming?

Some varieties are naturally lighter in foliage density and color but as far as I know, most tom plants should be at least a medium green rather than light green. Might try a foliar feeding on the runts or any light colored plants. If they respond positively within a few days, its a pretty solid clue that its time to sidedress and or waterfeed. I try to keep mine at just below a blue green but thats pretty close to the edge of too much and that can cause many problems including lack of set, BER and death. Take it slow and check with a foliar feeding first. Wetting foliage in the sun is a bad idea, wait for a shady time of day.

Good Luck.

I'm certainly not an expert, but I've always heard that too much nitrogen can inhibit fruit set, and possibly 6" of horse manure may be too much. (?)

diclemeg, here are my thoughts and questions. Way too many of them -- sorry -- just select the ones that seem relevant.

First of all, you have obvious height differences. The tall plants are setting fruit. The short ones aren't. That has to be significant.

So analyze the two groups for us. Are the tall ones and the short ones in different places, or interspersed? Were there any differences in how you planted them (buried one group deeper, used different fertilizers, etc.)? Do both groups get the same amount of sun?

What was growing in these areas last year? Any buried gravel, cement, lumber, etc.? Is one area lower or higher than the other, or with obviously better or worse drainage? Is the soil the same?

Are the short ones perhaps against a building or a fence?

Are the tall ones from one vendor, the short ones from the other vendor, or some of both?

Were both groups planted at the same time, or different dates? Can you tell us when? Or how much time between the two? (If there was no significant difference, don't go into details.)

Since the taller plants are the ones with fruit, and the shorter ones don't have fruit, I think we can discount the manure. If too much nitrogen were the problem, the plants without fruit should big huge, green, and aggressively healthy-looking.

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the ones that haven't mostly are between 18 inches and 3 feet, and some have curled leaves, some look atrophied

Leaves can curl for a number of reasons (including both too much water and too little). Or this might be herbicide damage. Do you know when you first noticed the curling? About how long ago was it? Were the two groups of plants about the same size until then?

Has anything been sprayed in the area in the past month or so? By you or a neighbor -- or even a neighbor's neighbor? Herbicide can drift incredibly far on the wind, and tomatoes are horrifically sensitive to it. Curled and twisted foliage is the main symptom.

If you know of any herbicide that was used, try to find out what it was (brand or chemical; whatever you can learn).

Have a look at these pictures of herbicide damage. Do they look at all like your plants?

http://images.google.com/images?hl=en&q=tomato+%22herbicide+damage%22&btnG=Search+Images&gbv=2&aq=f&oq=

Are these plants putting out any new foliage? Is it just as twisted?

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Daconil is used to prevent fungal diseases. I doubt your problem is fungus-related.

"We got tons of rain on the east coast in June,"

Yes, Indeed. I am south of Richmond, Petersburg area

" I'm soaking 8 foot deep in the trench"

Why are you soaking them after all this rain? I only had to water my plants lightly 2-3 times just to keep up the moisture when it was hot and dry for a week. And I got fruits -- even end blossom rott on some of them from too much rain and not enough sunshine.

I did feed my plants with liquid seeweed (from concentrate) early in May, but stopped feeding them when the green tomatoes started to appear.
Just my 2 cents

missingtheobvious.... thanks.... it is now apparent to me why...the ones that aren't growing well are closer to a fence, and go in shade after 5pm, whereas the others go in shade around 630. and the ones closer to fence were transplanted alot later.

of the six or so that are showing fruit, its interesting that three of them are of russian variety black krim, anna russian, black from tula

diclemeg, I'm glad you found my embarrassingly-long response helpful.

The fence question was actually a two-fer: it might indicate different conditions (in this case a bit less sun) or a nearness to a neighbor's possible herbicide.