There is a type of soil called a 'gley', which develops in anaerobic conditions.
Surface water gleys occur where the percolation of water is restricted by poor soil structure in the topsoil and subsoil, so producing a perched water table. This is especially common in clay soils (the clay particle itself is <0.002 mm in size and so the particles become compacted together very easily) and in wetter regions of the country.
Anaerobic conditions develop beneath the water table, causing the iron oxides that normally give soil its brown colour to become dull grey or blueish.
The extent of the waterlogging to which the soil has been subject to can be judged from the degree to which the soil is completely grey. Normally, there is a rusty, mottled pattern indicating that aerobic soil conditions do prevail for at least part of the year (e.g. in summer).
Gleys are usually slow to warm up in spring, on account of their high water content, which results in plants coming into growth later than on other soil types. There are also less beneficial organisms to be found in the soil e.g. earthworms, which leads to lowered nutrient levels and a reduction in plant growth.
Poor root penetration can also be a problem, resulting in slow establishment and poor anchorage.
The cold, wet nature of the soil may also increase the incidence of plant diseases.
Such soils can be considerably improved by incorporating plenty of bulky organic matter and grit.
The addition of lime can help by causing the clay particles to bind together into more stable aggregates and thus opens up the pore space in the soil.
The fusing of the stems of your golden rod is a physiological disorder known as fasciation.
It can be caused by a genetic mutation within the plant; damage to the growing tip by pests, frost, chemicals, etc ; viral infection or a bacterium called Rhodococcus fascians.
Fasciated shoots can cut out if you want, but in herbaceous plants, fasciation generally only lasts for that year anyway.
Hope this helps!