Swath Grazing - Frequently Asked Questions

In what direction should the field be planted?
Consider animal traffic patterns before planting. Where is the shelter from the wind, water supply, and bedding area? Animals should graze areas closest to these facilities at the start of the swath-grazing period. Seeding should be 90^o opposite to the direction of grazing. For example: if the animals will graze from east to west, the field should be planted north to south. Two reasons: 1) swaths will be supported better by rows of stubble that are perpendicular to the swath, and; 2) Cows having access to 10 to 20 feet of swath (from the butt end) results in less waste than letting cows consume feed from one swath that is 300 feet long.

When should the crop be cut for swath grazing?
In the past it's been recommended that crops should be swathed in late August / September or when the cereal crop is at the soft- to mid-dough stage, resulting in high quality forage. These recommendations came from research conducted for silage production.

However recent studies (Rosser et al., 2013) have shown that crops that are cut at the hard-dough stage result in higher dry matter yield without compromising forage intake, digestibility and digestible energy intake. This means more forage available to feed more cows. For example, barley cut for swath grazing at hard-dough stage can provide feed for 23 percent more cattle from the same land base with no extra cost. Oats has been shown to potentially feed 57 percent more cows if cut at a later stage. Actual forage yield, though, varies from year to year depending on growing conditions.

What machinery is best for cutting?
A swather is ideal for cutting the crop. Swaths as a result tend to be narrow and have significant depth. This makes it easier for the cows to find the material to graze when there is significant snow cover. Using a disc bine or mower lay the swaths flatter to the ground, break more stems and shatter seed heads (if crops are cut when more mature), making it more likely for cows to waste and trample the swaths. Increased crop contact with moist or wet ground can increase deterioration in forage quality and increase mould growth.

What if a crop is cut later or when it is more mature? How can it be managed then?
Mature crops will have more energy and protein concentrated in the seed heads. Cattle will tend to eat the heads first, and can experience acidosis, grain overload and bloat if they are allowed access to a large portion of the field.

If the crop is cut at a later stage of development, it will take 10 to 14 days to gradually introduce the animals to the swath grazing material. Start at 25% of the daily intake and increase by 10% every 2 to 3 days. Feed silage or hay in the morning to make up the difference in feed intake.

Material that is provided in the swath needs to be limited to what the animals consume in a day during the introduction. Animals should clean up both grain and straw before being moved to a new section of the field.

After the animals are adjusted to the swath grazing material, sufficient amounts of feed for 3 days of grazing can then be offered. Providing more material than this increases feed waste.

How could broad-leaf weeds be managed? Will they affect the quality of the crop?
Weeds can be controlled with a pre-seeding or in-crop herbicide treatment. Use a recommended herbicide for broad-leaf weed control. It is important to check the herbicide label for grazing and feeding restrictions.

Some broad-leaf weeds may have anti-quality factors that could cause reduced feed intake or toxicity if significant portions are found in the swaths. Stinkweed contains alkaloids that can cause gangrene of extremities; kochia, lambs quarters and pigweed have oxalates that can cause severe calcium deficiency. It's best to monitor the crop and manage accordingly. If a significant amount of weeds are found in swaths, grazing may need to be restricted to reduce potential problems. Supplemental feed will also be needed because of reduced intake.

How to manage swath grazing?
The use of electric fence is essential to control animal access to feed and to reduce waste. Cattle will tend to consume the higher-quality portions of the forage first, leaving the straw for last. Once the heads are consumed (cleaned off the forage), energy and protein levels in the feed are greatly reduced. This can cause impaction problems in cold weather and animals can lose condition. Using electric fence to provide new feeding areas on a regular basis will reduce wastage, sorting and trampling of the feed.

If using a strip-grazing system, the field should be first divided into two or more large sections (depending on the size of the field), and a second electric wire is used to section off smaller areas to be grazed for 1 or 3 days so that the animals are grazing off the butt ends of the swath. This will result in less waste by the animals.

Cattle going onto swath grazing from stubble fields, native or tame pastures will need to adjust to the new feed type slowly. Feed hay in the morning at 50% of the ration in the morning before turning them out, and provide supplemental hay for the first few days while they're grazing the swaths. Monitor animals for signs of distress (bloat, acidosis, grain overload) for the first week.

If the crop has experienced drought, cut after a frost, or was grown on heavily manured or fertilized fields, it is important to have the feed tested for nitrates.

Do animals require bedding and fresh water when swath grazing?
Providing a bedding pack reduces energy requirements of the animal by 10 to 15 %. Having a loafing area reduces manure contamination of the cut feed. Cows that lie in an area typically manure in the same are when they get up. Cows will not eat feed that is contaminated with manure.

Water is required if loose snow is not available to the animals. A lack of water will dramatically reduce feed intake within two or three days. For more information, please see Watering Cows with Snow - Frequently Asked Questions.

What are the concerns of swath grazing?
Monitor animal condition on a regular basis. Older more aggressive cows will consume the higher quality portions of the feed. Timid or young cows (first- and second-calvers) may only be able to consume the straw component of the swath after the mature cows have picked through the feed. If animals are getting thin remove them from the swath grazing area and feed separately to regain condition prior to colder weather. Extra supplementing with calcium and magnesium may also be needed.

What to watch for when swath grazing?

• Extreme weather conditions causing crusting snow and ice removes the water supply for the animals. Supplemental water sources will be needed immediately.
• Provide portable windbreaks to reduce exposure if bush areas or shelterbelts are not available.
• Cows that are still with calf should not be used to swath graze due to the possibility of the animals loosing condition.
• Growing cattle will need extra supplementation in the form of protein (such as peas or 32% beef supplement) to grow. If they are not gaining on the swaths they should be removed and fed separately to help them regain condition.
• If the area used for swath grazing is in areas with wildlife, these animals can damage or consume considerable amounts of forage in a short period of time.
• If the areas are not grazed properly, residue can be a problem when seeding a crop the following spring.