By: Sarah Sommerfeld, PAg, Regional Forage Specialist, Outlook
As a forage stand ages, the productivity and quality of that stand begins to decline. Some decline in productivity cannot be prevented, however good management cannot be overlooked. A decline in productivity may be noted as undesirable when plant species and weeds begin to dominate. Reduced forage production may also be attributed to poor stand management, nutrient export, soil limitations and unfavourable weather conditions. To improve the productivity of a stand, forage rejuvenation practices can be implemented.
Forage rejuvenation does not always require the stand to be terminated or aggressive tillage operations be used. Forage rejuvenation can be done through less aggressive field operations that manage, manipulate or enhance the existing vegetation.
A critical first step in the forage rejuvenation process is to identify the reason for the lost productivity. Realizing the difference between the actual problem and a symptom of the problem will help to address the type of rejuvenation that can be implemented. For example, invasion of undesirable plant species could be a symptom of poor grazing management or low soil fertility. When left unaddressed, the original cause of the reduction in productivity will undermine any rejuvenation practices.
An important thought to remember is that the success of any rejuvenation practice is very dependent on weather conditions and overall management practices. Each rejuvenation strategy has benefits as well as drawbacks. Each practice will involve economic considerations. Forage stands in fair condition may benefit from a less aggressive rejuvenation practice, and can return to good condition in one to three years. Forage stands in poor condition usually require a more expensive and aggressive rejuvenation practice, and often take a longer time to return to good condition.
The following chart provides a simplified overview of available rejuvenation options and can be used as a first step in the decision making process.