Soil pH, whether acidic or alkaline, is the result of a chemical imbalance, not the type of soil it is. If you do the research, soil pH is directly related to its mineral content and the amount of rainfall that area receives. Soils with a high limestone content will tends towards alkalinity; those with a granite base will be more acidic and various other minerals will influence pH as well depending on their composition. Areas with high rainfall will also tend to produce acidic soils while those areas that are more arid with lower rainfall - less than 20 inches per year - tend to be alkaline. It has nothing to do with a chemical imbalance - it is what it is depending on location and soil composition and the chemicals result from whatever minerals are providing them. Rather than an 'imbalance' it is the natural state of the chemicals and how they react with each other depending on the soil type. Most soils will have a buffering capacity that resists pH change in varying degrees. Clay soils and those that are high in organic matter have a greater buffering capacity and resist any significant changes in pH. Very sandy soils have much less buffering capacity. It is very difficult to change an acidic soil - generally those with a high clay content - to an alkaline state. Since organic matter tends towards a more acidic pH and also increases the buffering capacity of the mix, I'd lean towards reducing that portion of the mix. Generally for inground planting conditions, an organic content of no more than 5-10% is more than adequate. Raised bed conditions would dictate something quite similar.

What affect this might have on our environment, and us, is unknown since no research has been done to find out. The bulk of the modification done on any GMO'd crop is for disease, insect or pesticide resistance. For cotton, it is primarily insect resistance - the lack of need to spray insecticides is generally considered by most to be a good thing. Also cottonseed meal - like any other organic fertilizer - needs to go through a process of mineralization before they can be presented in a plant-accessible form. It is hard to consider that with all the necessary decomposition or consumption by soil organisms and the entire photosynthetic process some sort of deadly Frankengenes are going to come back and haunt us. Especially in the concentrations one would normal employ. Lets stay within context here :-)

1) Is there any tangible benefit in lowering my pH from 7.2 to the recommended 6.5? I wouldn't bother trying unless you have plants that show signs of iron chlorosis (yellow leaves with green veins). In that case, I'd treat the individual plants using sulfur buried in the soil. 2) Do I need to do anything about my lime %? From what I've read, lime is added to raise the pH, which is going in the wrong direction for my soil. I find it more than a little odd that you'd have a low level of lime. I wonder if you have calcium in other forms. I would not do anything about that unless it's causing problems. As you noted, adding lime will exacerbate the pH situation. 3) It seems like I could bump up both my N and OM by adding a few bags of steer manure. Does anybody have any numbers on %N by weight, or lbs N per cu ft, for composted steer manure? N will always show up on soil tests as low, unless you've just fertilized. N just doesn't stick around long in the soil. Steer manure, particularly the bagged stuff, is more of an amendment than a fertilizer, so you won't be adding much N with that. One caution on using manure in the intermountain west is that it can have relatively high salt levels and salinity can be a problem here due to the low rainfall (same thing that contributes to the high pH). I'd add shredded leaves from any trees (unless you're mulch mowing them), coffee grounds from Starbucks (or other coffee shops, but Starbucks has a corporate policy of making them available for free to gardeners), shredded tree trimming (some tree services will supply them for free), and anything else you can get for free. Note that if you spread 3 cu yds per 1000 sq ft all at once, you'll smother the lawn. If you use tree leaves and/or shredded trees, either spread them on top, or, if you incorporate them into the soil, add a nitrogen source so they'll decompose readily and not make N unavailable to the plants. If you use coffee grounds, don't spread them in layers more than about 1/2 inch thick, because they can crust over and repel water when they dry. Coffee grounds are a source of nitrogen (about 2.5% nitrogen).

The notion that clematis require or prefer alkaline soil is just one of a number of myths associated with this vine. Clematis species are native to numerous locations across the temperate regions of the globe and soil conditions vary widely. Some species may have more strict requirements but in general, clematis are not very fussy about pH......they are quite happy in both slightly to moderately acidic soil (pH 6.0-6.5), neutral soil (7.0) or slightly alkaline soil (7.5). Ideally, I'd target somewhere close to neutral (6.5-7.0) -- just avoid extremes in either direction :-) The American Clematis Society doesn't even address the question of pH being an issue! It is more important that the soil be loose and friable and with a fair amount of organic matter included. And with very good drainage. FWIW, I have grown a large number of clematis (60+) in moderately acidic soil (pH 6.3) without any issues. I even used to grow them up and through large rhododendrons, recognized acid lovers. I have never applied lime nor do I fertilize very heavily. I mulch well with compost each season and when I had rabbits, used their manure liberally. That's it....no other amendments or fertilizers. Lush, robust plants and with a profusion of flowers.