Every Monday for the past couple of months on the OSU Extension crop team conference call I have heard Jim Noel from the National Weather Service say that across Ohio we are in a pattern of above average temperatures and below average rainfall.
These are not encouraging words for a grazier to hear. This isn’t the type of forecast conducive to good pasture growth. Summer pasture growth is dependent upon rainfall and pasture management. Rainfall we can’t control. Management though is a different story.
So what’s your plan to manage through a hot, dry summer? Regardless of the weather pattern, you should stick to what you know as a grazier, as a manager of pasture plants.
Those pasture management principles that you learned at a grazing school, or through a grazing council or from an experienced grazier will serve you in good stead through this weather pattern. Let’s review those principles and how they are applied when it is hot and dry.
The take half, leave half principle must be followed during the summer months. That remaining leaf area provides a photosynthetic base for plant regrowth, shades the soil to keep the soil temperature cooler, and it helps to reduce soil moisture loss.
Do not cheat on this principle during hot, dry spells. It is critical to maintain a 4-inch grass height to get the benefits mentioned. Maintaining this leaf residue provides the grass plant the best opportunity to take advantage of those spotty rain events that are common to hot, dry years, allowing regrow much sooner than overgrazed pasture paddocks.
The second principle that must be adhered to is to provide a rest period that is sufficient to allow plants to grow back to a practical grazing height. The height at which grazing should begin is somewhere in the 8- to 10-inch range.
Obviously the two principles work hand in hand. In practice this means that grazing rotations slow down during hot, dry periods. It is easy to do just the opposite.
Grass is growing slowly. In order to maintain a 4-inch residual I move my livestock into the next paddock a little early. Maybe the grass is only 7 inches tall. If I want to maintain a 4-inch residue, I’ll have to leave this paddock a little sooner than the time my livestock can normally graze in this paddock.
The grass in my next scheduled paddock is only 6 inches tall. Maybe I should just let them graze this current paddock down a little bit lower, say 3 inches.
This pattern continues and soon I am either grazing down to a 2-inch height, which pretty much stops regrowth during 90 degree days with no rainfall, or I am trying to get my livestock to only take off an inch or two of grass growth, which is pretty tough to do.
The end result is that paddock moves are speeding up and leaving behind paddocks that are overgrazed. The next rotation puts me in even worst shape.
What’s the answer? Stick to what you know. Maintain a leaf residue of about 4 inches and do not start a grazing pass unless the paddock is 8- to 10-inches tall.
Impossible! The grass is not growing fast enough. Yes, I know. That means you must have a sacrifice area in order to maintain these grazing principles and protect the majority of your pasture paddocks.
The sacrifice area might be a barnyard lot or maybe it is a pasture paddock. If it is a pasture paddock it will get overgrazed and beat into the dirt while you wait for sufficient pasture growth to resume your grazing rotation. It means that hay will have to be fed.
This is a disaster! Is it? It is not desirable situation, I’ll grant you that, but the disaster would be overgrazing every paddock, ending the grazing season in July, and facing an extra-long period of hay feeding beginning in late summer.
By sticking to what you know, and using a sacrifice area, you make the best of a tough situation and put yourself in the position to be able to resume grazing when rain occurs and temperatures cool down.
There is still the possibility of stockpiling grass for late fall and winter grazing because you have protected most of your grass plants. Feeding some hay while in a sacrifice lot is really using hay as a management tool.
The end result will be less total hay fed in the year if grazing is able to resume later in the summer and throughout the fall. Feeding hay in the summer in a dry lot beats feeding hay late in the fall or winter in cold and/or muddy conditions.
Finally, if the sacrifice lot must be a pasture paddock, choose one where some renovation is needed and new improved pasture varieties can be planted. Ideally this might be a paddock where you could do some tillage after your pasture rotation begins again.
This would provide the option to plant a late summer forage option such as a cereal grain like oats, wheat or rye or a brassica like turnips. Any of these forages could provide some fall and early winter grazing. The paddock would then be set up for an early spring planting to return to a perennial pasture mix.
Hot, dry summers are a challenge to the grazier. Pasture management is the only factor that can be controlled. Stick to what you know as you make those management decisions.