Leafies have been selected to have stalks that are composed of an appropriate balance of effective and digestible fiber for the silage ration. When examining the digestibility of the corn stalk, we know that the stalk below the ear consists of more non-digestible heavily lignifled fiber that is needed to support the weight of the ear. Leafy hybrids have been selected to have a lower ear position on the plant to reduce the amount of overall plant lignin and to increase the digestible fiber found above the ear. The total stalk is strong enough to reach silage maturity. Compare that to a grain hybrid that is bred to have higher ears for combining and stronger more lignin-filled stalks to last weeks or months beyond silage harvest. It just makes sense that Leafles offer a better balance of effective and digestible fiber for silage feeding.The Digestible Ear
Leafles have been bred to have large ears. Unlike the ears of grain varieties, a Leafy ear is composed of large kernels that dry slowly on large digestible cobs. The kernels have lower test weight if taken to grain maturity because they are composed of more floury white starch and less vitreous starch. The large, moist, more floury kernels break into smaller pieces during harvest processing. This smaller particle size allows more sites of digestion for rumen microbes. Combined with higher kernel moisture, the silage can be economically fed right after fermentation.
Leafy hybrids have been bred for an extended silage harvest window. The Leaty plant is designed to dry down at a rate that compliments the ear, while maintaining plant health. Leafy ears have slow drying kernels that remain soft through the ideal whole plant silage moisture range of 62-68%. During a study at the University of Wisconsin, researchers harvested plots of a Leafy and a Dual Purpose hybrid at as close to 65% moisture as possible. They then left a couple of rows of each variety standing in the field and returned weekly to test kernel moisture. After three weeks, the Leafy still had a kernel moisture of 30%. This slow kernel drydown helps preserve starch digestibility.Population
Leafies perform better when planted at 28,000 to 30,000 plants per acre (ppa). Our population studies have shown that Leafies planted at 28,000 ppa have thicker stalks and bigger ears than Leafies planted at 35,000 ppa. The thicker stalks are more digestible and the bigger ears make a silage that contains a higher percentage of overall starch.
It is essential to grow Leafies at their intended populations. Increasing density can alter flowering dates and maturity, drought response, standability and overall plant composition, all of which affect the feeding value of the silage product.
For the best crop security and yield, grow Leafy hybrids at 28,000 ppa.
Leafy Floury hybrids feature the same silage-specific characteristics as Leafy hybrids with the addition of more ruminally-available starch for milk production. This bump in floury starch is achieved by the presence of a naturally occurring recessive gene called opaque-i. Since the opaque-i gene is recessive, Leafy Floury hybrids produce 25% full-floury kernels. The remaining 75% are typical of Leafy’s soft, slow-drying digestible starch.Smaller Particle Size
Floury kernels are softer and fracture into finer particles during silage harvest. This fine particle size translates into higher quantities of available starch right after fermentation is complete and allows the silage to be fed more rapidly with less dry matter loss. Leafy Floury hybrids can be fed soon after chopping and some dairies have fed a Leafy Floury ration immediately with no milk slump when compared to the ration of year-old silage.More Starch Digestibility
Seven hour starch tests have revealed that Leafy Floury hybrids have 5-1 2% more starch digestibility than a regular Leafy hybrid. A 7-hour starch test measures ruminally-available starch, and a higher rate of starch disappearance is thought to indicate rumen starch conversion to milk production, rather than to body maintenance. Leafy Floury hybrids also have higher 2-hour and 4-hour starch disappearance values.
We recommend that a 7-hr starch analysis be run on silage as an indication of feed value. Farmers who have used Leafy Floury hybrids have told us they are able to reduce the quantity of concentrate corn in the total mixed ration and still maintain milk production and milk component levels.
Leafy Floury hybrids are versatile. They can be balanced in a ration for high- producing cow groups and maintenance groups. Dry cow rations balanced with Leafy Floury are relatively simple high corn rations. Leafy Floury hybrids exist to meet hybrid needs from an 85 to 1 1 0 day maturity range.
Left: A Leafy Floury ear shaved to reveal kernel interiors - 25% of kernels are floury whde the rest are typical of Leafy’s semi-floury kernel type.
Right: A Floury kernel split in half to reveal a completely floury interior.