| | Grazing in early spring, prior to pasture readiness, deprives grass plants of needed leaf area and reduces grass growth, herbage production and economic returns. In spring, pasture plants are near the bottom of their food reserves (top of their operating loan). As plants start to grow they use their reserves and just before they reach the 3-leaf stage they max out their "operating loan". If grazed before the 3 to 3.5 leaf stage they are taken into an "overdraft position". The interest rate on plant overdraft is a credit card rate. Working on overdraft is a costly financial spot for an operation and a pasture.
Perennial forage plants in pastures continue their life cycle from one year to the next. Their needs revolve like a farm operating loan. The environment can affect grass or legume plants positively or negatively, and the impact is compounded annually. In fall, plants slowly stop growth and go dormant. During winter, they go dormant, drawing on food stores in roots and stem bases (their operating loan). In a drought, when growth stops earlier, plant dormancy and use of food reserves is longer (negotiating a larger operating loan). Plant food stores fluctuate up and down throughout the year, much like a farm operating loan. In drought years, high insect damage, or with overgrazed pastures not enough biological time given for plant regrowth to fully recover from the last grazing incidence the operating loan may not be zeroed. This creates high plant expenses without enough profit adequate biological time given for rest and recovery regrowth left to pay down debt. Positive or negative effects are cumulative from year to year. If negatives outweigh positives, plants can lose health, production ability and die. As losses build up, pastures become less productive, sodbound (operating loan at maximum, then overdraft) and need to be rejuvenated (inflow of outside cash).
To maintain healthy tame or native pasture, grazing in spring should start only after the 3 to 3.5 leaf stage. This is important for rejuvenation of pastures damaged by drought, grasshoppers and overgrazing. Taller growing grasses like meadow brome or orchard grass are ready to start grazing when they are about 6 to 8 inches tall, while lower growing types like creeping red fescue or Kentucky bluegrass are ready at 4 to 6 inches. Couple this later spring grazing with good grazing management to help maximize returns.
Rest in spring is crucial for pastures that were overgrazed, or drought stricken in the previous year. It is the cheapest ways to help rejuventate them. As a rule of thumb, these pastures should be grazed 2 to 4 weeks later in spring than normal and then only lightly. They also need suitable rest periods between grazings. These rest periods need to be long enough for plants to regrow 3 to 3.5 new leaves. In drought, regrowth is slower so rest periods need to be longer. Also, the more residual growth left after any grazing, the faster cattle can be brought back. This is where sayings like " it takes grass to grow grass" or "take care of the grass and the grass will take care of your operating loan" come from. Adding fertility may help plants recover more quickly after grazing if moisture is adequate.
Producers who hold animals back in spring time and graze 2- 4 weeks later than normal are very surprised at how a previously overgrazed or drought stricken pasture yields later in the year of rejuvenation. By understanding and monitoring plant growth a grazier has the greatest ability to make wise grazing decisions that will be profitable in the short term and help pay down the operating loan for profitable grazing in the long term.
Grant Lastiwka, Pasture Specialist,
Western Forage Beef Group / AAFRD, Olds |
|