Hi Michael-

First, my apologies for the delay in getting you an answer- we don't have an expert in your area right now and this question took a while to get routed to me.

Plants need nutrients, water, and sunlight to grow, as you know. It sounds like the nutrients that your grass was using for some time was provided by artificial means and your water is limited...which of course it is because we live in the arid West! In the event your plants don't get enough water and nutrients, they will likely survive but won't produce as much as they would without the supplementation. I'm guessing you've seen reduced growth as a result, which in and of itself is no big deal if you're not relying on it for an economic reason or for your own animals. If you start seeing more bare ground, however, that is a bigger deal because it means you're actually losing plants permanently, not just growth.

It sounds like your land has been used fairly regularly in the past. I think your limited grazing sounds like a solid management decision to help allow plants time to regrow. Years of rest (which is what I think you're referring to) are especially important when drought conditions occur, but can also be effective in 'good' years to ensure root growth takes place and the plant can reseed and add seed back into the soil. You are correct that soil cover is a good thing: bare soils are typically hotter, drier, and have less good microbial and fungal activity.

While rest is a good thing, it is also important to remember that grass developed over eons with grazing taking place by foraging animals. Your grass can benefit from 'cutting,' whether by a foraging animal or a machine as long as enough is left for the plant to continue to photosynthesize and have plenty of time to regrow before it goes into fall dormancy. This important period is a period we refer to as 'rest,' too. Note that rest is NOT when the plant is dormant; the rest period needs to be while the plant is growing. 

In short, a year rest can be beneficial, but long-term nonuse isn't the answer, either- grass needs to be grazed or hayed at the right times and the correct amounts, too, in order to stay healthy and make sure that too much growth and dead matter doesn't accumulate on the soil. As with everything, balance is the key.

Note that if you don't harvest your grass or graze and enjoy ag tax status on your property, your decision can negatively impact the discount you enjoy. Make sure to talk to your local accessor to discuss your tax status before making long-term decisions.

Let me know if you have other questions. Happy Memorial Day.

Todd