Harvest Management

Table 1. Overview of Hay Production in Common Perennial Forages grown in Georgia.

¹Poor designation refers to economics not agronomics.

Types of Harvested Forages

Forages can be harvested or conserved as both hay and baleage. Hay is defined as forage stored in square or round bales at less than 20% moisture. Baleage (or baled silage) is defined as forage stored in a round bale between 40 and 60% moisture.

Perennial forages are generally not recommended for baleage production because the low plant sugars and high buffering capacity make fermentation difficult. In addition, the relatively low forage quality will likely not justify the added cost of baleage equipment and plastic wrap. If you have more questions about baleage production please visit B1532, Baleage Production and Use and B1508, Baleage Frequently Asked Questions.

Steps for Producing High Quality Hay

Mowing

Ideally, a hay mower with a flail, impeller, or tine type conditioner will be used to cut the grass to the recommended stubble height. Conditioners are used to increase the surface area and reduce drying time. A mower without a conditioner can also be used, however drying time will be slower.

Mowers with roller or crimper type conditioners are generally not recommended for use in fine-stemmed grass forages systems because the conditioner is not as effective as the flail type. Bermudagrass, bahiagrass, and tall fescue are all defined as fine-stemmed grasses regardless of the specific variety.

Tedding

A tedder may be used to speed the drying process by spreading forage out of the mower’s swath rows and increasing surface area for drying. Tedding this material may cause significant leaf loss if the implement is not properly adjusted or it is used on forage below 50% moisture or without a dew.

A tedder is not necessarily a replacement for a mower conditioner and vice versa. The benefit of using a mower conditioner and a tedder is synergistic, meaning the reduction of drying time when operating both implements exceeds the sum of each individual implement.

Raking

A hay rake must be used to merge the swath rows into windrows after the grass is allowed to wilt to the desired moisture, usually 10-15% above the baling moisture. There are several types of hay rakes available on the market today.

Rotary rakes are preferred because they are less destructive than wheel, V, or speed rakes. Rotary rakes are powered by the tractor’s PTO, not ground driven as in the case of the other two rakes. This allows the forage to be gently swept into a windrow with the rotary baskets, rather than being pushed or pulled across the ground. This can help you retain more leaves and reduce ash content of the harvested material. Rotary rakes also create taller, “fluffier” windrows, which allows for better air flow and improved drying rates. This allows you to rake the grass at a higher level of moisture, which will further improve leaf retention.

Parallel bar rakes are also an option, but they are generally less common in the hay industry than the other two styles because of the narrow working width. These rakes are also ground driven like a wheel rake but are much less aggressive. If a ground driven rakes must be used, adjust the tines such that they minimize contact with the ground.

Baling

Balers are used to accumulate the forage to be stored in its final product. Hay can be baled with a square or round baler. Overall, round balers are more commonly used in Georgia. The ideal baler will be based on your desired product type and local service availability. Round baled forages are more common for cow-calf production. Square baled forages are more common for equine or export markets. 

Factors Affecting Hay Drying Time

It typically takes 3 to 5 days to complete the steps of hay harvesting. Improvements in hay technology can speed this process but weather is just as influential. There are several environmental factors that impact hay drying time. These include:

• Air temperature: warmer temperatures = faster drying
• Soil temperature: warmer temperatures = faster drying
• Wind speed and direction: higher wind speeds = faster drying
• Relative humidity: lower humidity = faster drying
• Sunlight: more sunlight and fewer clouds = faster drying

In short, hay dries faster when it is warmer, windier, drier, and sunnier!

Hay preservatives include organic acids, usually propionic acid. These can be used to reduce heating potential, maintain forage quality, and minimize mold development. They should only be used as an insurance policy, not as an excuse to rush the drying and baling process. 

Storing Harvested Forages

Hay can lose more than 25% of its nutrients if stored improperly. Ideally, all hay should be stored in a well-ventilated barn under cover. This may not be feasible for all livestock owners, especially if they are storing round bales, or construction time may be prolonged.

If hay must be stored outside, it should be in rows with the flat side of the round bales pushed tightly against each other. Leave a space of at least 4 to 5 feet between the rows of hay to allow air flow between the rows. This also allows space for vegetation control around the bales. The hay should always be stored in a well-drained site but raising the bales off the soil’s surface will further minimize storage losses. There are many options but the most common are gravel surfaces, old tires, or pallets. If possible, store the bales in a north/south orientation to maximize drying time across the entire bale surface as the sun moves east to west.

Testing Harvested Forages

Each lot of forage should be tested separately. A “lot” is defined as hay that was managed the same and harvested at the same time, out of the same field, and under the same conditions. Ideally hay should be tested after baling or purchase and again before feeding if the difference between the two time points is greater than 4-8 weeks and the hay is stored outside to account for storage losses.

To sample the hay, use the following protocol. Most University of Georgia County Extension Offices have a hay probe available for use.

1. Using a hay coring probe, collect 15-20 cores from each lot.
2. Insert the hay probe on the side of the bale, coring towards the center so you cross several windrows. This means you will core through the plastic wrap on a net-wrapped round bale, between the twine rows on a twine-wrapped round bale, and between the twine on the end (small side) of the square bales.
3. Remove the hay probe and empty the contents into a clean container (i.e. bucket or bag).
4.  Mix the material thoroughly to decrease bias. Pour in enough sample to fill up a 1-quart plastic bag.
5. Label each sample to make it easy to remember the location and lot sampled.
6. Fill out the University of Georgia Feed and Forage Testing Application, attach the form to the sample, and submit via the University of Georgia County Extension Office.

For more information on reading and understanding forage test reports, please refer to C1287, Unless you test, it's just a guess: How to take, interpret, and utilize a forage sample.