In late July 2012, I visited the Cornell-sponsored Valatie Research Farm. That part of Columbia County, NY, had received less than a half-inch of rainfall between early June and the date of my visit. During that six-week moisture deficiency, almost all the corn demonstration plots had dehydrated fatally. The precipitation lack was clearly the worst on soils where weed control demonstrations over the years had severely depleted soil organic matter (OM). Typically, those OMs fell in the 2.5% – 2.9% range. Most corn demonstration plots had shriveled up and died – particularly on those super low OMs.
While shocked at how poorly corn was faring at Valatie, I was amazed at how well hot climate summer annuals (HCSAs) were performing. In this grouping, we find sorghums, sudangrasses, their hybrids and millets. They appeared totally unfazed by the extreme lack of moisture. This isn’t a total surprise, since HCSAs were developed in areas where 10 inches of annual rainfall is common, such as sub-Saharan Africa. Unlike these HCSAs, corn originated in Central America, which has abundant rainfall.
The nutrient “responsible” for managing moisture metabolism in plants is potassium (K). K also regulates fluid metabolism in animals (potassium carbonate is a key electrolyte in Gatorade). K deficiencies are commonly responsible for corn plants lodging, premature leaf loss, reduced resistance to mold and moisture metabolism regulation. The natural K-supplying ability is reduced on larger soil particles, like sands and larger silts. Much tinier clays – due to their higher surface area-to-mass ratios – tend to supply more K to plants than do silts and sands. Soils also build up OM much more easily with clays than they do with silts and sands.
The soil’s moisture reservoir capability varies directly with its amount of OM. USDA data show that each 1% loss of OM reduces the soil’s water holding capacity by about 16,000 gallons/acre – about three pints water storage per square foot. OM also serves to store negatively charged nutrients, like nitrates, phosphates and sulfates. The increasingly common soy/corn non-rotation (absent autumn cover crops or winter forages) slowly but surely dissipates soil OM, ultimately undermining the soil’s ability to store water. This development proves problematic, both when moisture is lacking as well as when it’s excessive.
In his office’s bi-monthly news magazine Extension Express, Rich Taber, CCE Chenango, wrote an article titled “2022: Livestock Producers Dealing with Drought!” I’ll quote his lead paragraph directly, then hit the high spots of the rest of his text: “I have lived in Central New York for 43 years, and do not remember a drought year as bad as this one. Yes, we’ve had a few drier than normal summers, but nothing like this year. The summer of 2021 was exactly the opposite! Last summer hayfields lay unmown for much of the summer because of the constant on-and-off rain that we had, and hay quality suffered for that. However, at least the pastures grew very well! The normal summer slump in grass production – that occurs almost every year – was minimal. This year, however, grass growth had all but stopped completely! How should we contend with this calamity, which many of us don’t have a lot of experience dealing with?”
He begins answering this question by stating that livestock people making their own hay have a much smaller hay inventory compared to 12 months earlier. He states that in our region, first cutting for most folks was about normal, quantity-wise, since late May and June conditions were basically satisfactory. Then he said that second and third cuttings of grass fields were way down, impacted by severe lack of rain. This was unlike alfalfa fields, which (fortunately, with much deeper root systems) were able to find moisture farther down. He stressed that whether they make their own hay or buy it in (or some of both), livestock people should consider lining up hay purchases this summer, before prices climb to higher levels during the off-pasture season.
Quoting Taber again: “I see hay for sale frequently on social media for about the same prices as last year, so don’t wait too long, as the prices have nowhere to go but up in the coming months! You might even consider selling a few animals to lower your feed needs but watch the market carefully so that you don’t take a bath on their prices. Much of the South, especially Texas, has been liquidating their herds because of almost total lack of pastures and hay. Market prices will be in disarray for quite some time.” In terms of grazing considerations, it may be necessary to feed some of the hay allocated for winter. It will likely be necessary to increase paddock resting intervals. A rule here: The shorter the grazed stubble, the longer the recovery period. Serious graziers get annoyed when they see other peoples’ herds burning down continuously grazed pastures through summer. Managing pastures in this fashion is poor strategy in the best of times; in a drought year – with less roughage to graze – such traumatized paddocks are particularly slow to recover.
In support of these ideas, let me revisit the wisdom of Greg Braun, a renowned livestock/cropping guru, who farms in Tennessee. Quoting Braun: “Maintaining adequate live plant residual is critical in keeping the plant growing and thriving. A bale fed in early spring – and waiting till the grass is ready – will be worth four bales of summer grass production later – not to mention the fertility transfer back to the soil.” That’s a 300% return on investment!
He asks graziers not to allow livestock to chomp down legumes to less than 10 inches height during early spring – nor let them graze grasses shorter than six inches. Braun and I both believe that this principle also applies to autumn grazing. Feeding livestock a bale on a “sacrifice” paddock this autumn – for the greater good of paddocks in recovery – should yield the same ROI next grazing season.