For the last 150 years or so, much of our rangeland has been continuously grazed, at first by exceedingly high numbers of livestock then ever lessoning numbers as the rangeland could not support those previously high numbers. Never receiving the rest that is essential for recovery from that grazing. The range moved from the high quality-predominantly red range to white range, then moved progressively toward gray range. Bare soil has been increasing at various amounts all through this rangeland paradox. It is sad as one travels across vast areas of the western US to observe this phenomenon on an ever-increasing scale. In my lifetime it is quite noticeable what is happening. A drive down the highway going west of my headquarters is a sad experience, with reference to rangeland health. Yes, desert conditions have long been known in this area, but as time moves along it is becoming ever more noticeable that it is truly becoming a desert that is very hard to recover from.
As old-moribund grasses die and they are not replaced by new seedlings because of soil capping and loss of fertility, the soil is exposed to the elements and much of the humus and soil microbes are lost mainly to wind, water erosion and lack of cover for protection. This is a slow process that most ranchmen never notice until the ranchland is baren with little hope for recovery. A wet spell or extended rainy season can produce numerous annuals as nature abhors a barren landscape and does everything possible to cover the soil. Be it brush or annuals it will try to repair the damage done. Many times, the resource manager perceives the problem to be the encroachment of the brush, extended dry spells and even the nuisance of the annuals as being the cause of the slow desertification of the landscape. (I am told California is in the annual plants predicament as few perennials are currently present in many areas.) These are only symptoms of the overall problem and trying to correct the issues will most likely be futile without correcting the cause, which is generally one of two issues. Lack of animal impact and-or little time for recovery from grazing animals albeit wildlife or domestic livestock.
The Ace Reid comic strip below has more truth than many realize. Extended rest for long periods (12 years) will only lead to further desertification.