source: Farm and Food Report
The abundance of rainfall most of the province has received this year, combined with its impact in terms of moisture for forage growth, may provide ideal conditions to prepare for drought, according to Saskatchewan Agriculture and Food Rangeland and Forage Agrologist Dale Weisbrot.
“Because Saskatchewan is a semi-arid climate, we will experience the dry growing seasons again. It is not a question of if, it is a question of when we will encounter another extended dry period or drought. This year’s wet spring is providing land managers an opportunity to give some of the harder hit pastures more rest. From the forage perspective these fields are under rested, and the plants have not had adequate time to replenish themselves before they are grazed again.”
This year, longer rest can be planned and even a full year of rest for certain fields may be attainable. The rest will pay-off in increased litter accumulation, improved plant vigour and hastened post-drought range recovery. To facilitate this, sound range planning can allow control of livestock behaviour to achieve management goals, says Weisbrot.
“Range management can be defined as the art and science of manipulating, using and conserving grazing land resources, while maintaining ecosystem integrity. “There are some basic principles of range or pasture management that lead to increased livestock production and improved watershed and ecosystem stability, along with long-term sustainability.”
These principles are: graze the range or pasture at the right time of the year and to the right degree; leave adequate leaf area for re-growth to ensure the restoration of individual plant vigour; allow adequate rest for the forage in your pastures by keeping livestock off the range for a period during the active growing season, to allow adequate re-growth for the next year; and control livestock distribution and access to minimize selective grazing and prevent re-grazing of plants.
“These principles are applicable to both tame and native pastures. Grazing can have long-term negative effects if these principles are not followed. Poor management will lead initially to reduced plant vigour. Continued poor management will cause a loss of valuable forage plants, drought resistance, ground cover and range productivity.”
Ultimately, the condition or health of the range will deteriorate to such an extent that animal weight gains and productivity will be negatively affected.
“Understanding that plants obtain their energy from sunlight by producing carbohydrates through photosynthesis is crucial. In order for perennial pasture grasses to remain productive, the photosynthetic process must first feed the plant before it can provide feed for animals.”
Photosynthesis takes place in green plant cells—generally in the leaf—and produces carbohydrates for the plant. Carbohydrates are used for plant growth, maintenance, storage and reproduction.
“In plants, growth is the first priority for the carbohydrates available. If the green leafy areas of actively growing plants are repeatedly removed or consumed—either grazed, clipped or mowed— the plant will use energy that it stored from previous production to continually attempt to replace the leafy areas.”
If the plant’s leafy area produces more than enough carbohydrates to meet the growth and maintenance demands, then the excess becomes available for storage.
“Since growth has priority over storage for available carbohydrates, repeated defoliation—heavy uncontrolled grazing—during the growing season will seriously deplete a plant’s stored carbohydrates. This repeated interruption of a plant’s capacity to store energy is the basis for using grazing or mowing as a tool for weed control or vegetation management.”
It is important to note that carbohydrate storage increases when the growth rate slows and the leaf area is large. Conversely, carbohydrate storage decreases when leaf area is small and growth rate is fast.
“Perennial plants must have sufficient stored energy to survive the winter, to begin growth the following spring and recover after complete defoliation. Defoliation occurs as a result of grazing but also as a result of clipping, mowing and other events such as disease, insects, frost and hail,” explains Weisbrot.
Adequate levels of carbohydrates that help ensure a long-lived and vigorous perennial forage stand can best be maintained by delaying defoliation, or keeping early defoliation periods short; by allowing adequate leaf area to remain after defoliation; by allowing adequate time between defoliations to permit leaf area and carbohydrate reserves to build; and by allowing adequate residual leaf area and time late in the season to permit carbohydrate build-up and bud development.
Weisbrot believes these suggestions will help rest some pastures, allowing the plants to build up their own reserves and improve their vigour.
“Because feed is relatively inexpensive now, compared to during periods of feed shortages, purchase is also an option – this feed can be used to help rest some pastures. However, take care to test the feed for nitrate content due to last year’s frost damaged green feed.”
Lastly, “crop residues are likely to be significant this year and an opportunity for increased stubble grazing may be available,” advises Weisbrot.
For more information, call the Agriculture Knowledge Centre at 1-866-457-2377.
For more information, contact:
Dale Weisbrot PAg, CPRM
Forage Development Specialist, Rangland Ecology
Saskatchewan Agriculture and Food
(306) 787-9476
The abundance of rainfall most of the province has received this year, combined with its impact in terms of moisture for forage growth, may provide ideal conditions to prepare for drought, according to Saskatchewan Agriculture and Food Rangeland and Forage Agrologist Dale Weisbrot.
“Because Saskatchewan is a semi-arid climate, we will experience the dry growing seasons again. It is not a question of if, it is a question of when we will encounter another extended dry period or drought. This year’s wet spring is providing land managers an opportunity to give some of the harder hit pastures more rest. From the forage perspective these fields are under rested, and the plants have not had adequate time to replenish themselves before they are grazed again.”
This year, longer rest can be planned and even a full year of rest for certain fields may be attainable. The rest will pay-off in increased litter accumulation, improved plant vigour and hastened post-drought range recovery. To facilitate this, sound range planning can allow control of livestock behaviour to achieve management goals, says Weisbrot.
“Range management can be defined as the art and science of manipulating, using and conserving grazing land resources, while maintaining ecosystem integrity. “There are some basic principles of range or pasture management that lead to increased livestock production and improved watershed and ecosystem stability, along with long-term sustainability.”
These principles are: graze the range or pasture at the right time of the year and to the right degree; leave adequate leaf area for re-growth to ensure the restoration of individual plant vigour; allow adequate rest for the forage in your pastures by keeping livestock off the range for a period during the active growing season, to allow adequate re-growth for the next year; and control livestock distribution and access to minimize selective grazing and prevent re-grazing of plants.
“These principles are applicable to both tame and native pastures. Grazing can have long-term negative effects if these principles are not followed. Poor management will lead initially to reduced plant vigour. Continued poor management will cause a loss of valuable forage plants, drought resistance, ground cover and range productivity.”
Ultimately, the condition or health of the range will deteriorate to such an extent that animal weight gains and productivity will be negatively affected.
“Understanding that plants obtain their energy from sunlight by producing carbohydrates through photosynthesis is crucial. In order for perennial pasture grasses to remain productive, the photosynthetic process must first feed the plant before it can provide feed for animals.”
Photosynthesis takes place in green plant cells—generally in the leaf—and produces carbohydrates for the plant. Carbohydrates are used for plant growth, maintenance, storage and reproduction.
“In plants, growth is the first priority for the carbohydrates available. If the green leafy areas of actively growing plants are repeatedly removed or consumed—either grazed, clipped or mowed— the plant will use energy that it stored from previous production to continually attempt to replace the leafy areas.”
If the plant’s leafy area produces more than enough carbohydrates to meet the growth and maintenance demands, then the excess becomes available for storage.
“Since growth has priority over storage for available carbohydrates, repeated defoliation—heavy uncontrolled grazing—during the growing season will seriously deplete a plant’s stored carbohydrates. This repeated interruption of a plant’s capacity to store energy is the basis for using grazing or mowing as a tool for weed control or vegetation management.”
It is important to note that carbohydrate storage increases when the growth rate slows and the leaf area is large. Conversely, carbohydrate storage decreases when leaf area is small and growth rate is fast.
“Perennial plants must have sufficient stored energy to survive the winter, to begin growth the following spring and recover after complete defoliation. Defoliation occurs as a result of grazing but also as a result of clipping, mowing and other events such as disease, insects, frost and hail,” explains Weisbrot.
Adequate levels of carbohydrates that help ensure a long-lived and vigorous perennial forage stand can best be maintained by delaying defoliation, or keeping early defoliation periods short; by allowing adequate leaf area to remain after defoliation; by allowing adequate time between defoliations to permit leaf area and carbohydrate reserves to build; and by allowing adequate residual leaf area and time late in the season to permit carbohydrate build-up and bud development.
Weisbrot believes these suggestions will help rest some pastures, allowing the plants to build up their own reserves and improve their vigour.
“Because feed is relatively inexpensive now, compared to during periods of feed shortages, purchase is also an option – this feed can be used to help rest some pastures. However, take care to test the feed for nitrate content due to last year’s frost damaged green feed.”
Lastly, “crop residues are likely to be significant this year and an opportunity for increased stubble grazing may be available,” advises Weisbrot.
For more information, call the Agriculture Knowledge Centre at 1-866-457-2377.
For more information, contact:
Dale Weisbrot PAg, CPRM
Forage Development Specialist, Rangland Ecology
Saskatchewan Agriculture and Food
(306) 787-9476
Comments