Improving Forage Quality: Dreams vs. Reality - Penn State University

Corn hybrid selection
Leafy hybrids
Most leafy hybrids are “silage silage only” only hybrids, but a few
are promoted as dual-purpose
dual purpose—for for grain or silage.
Leafy hybrids have up to twice as many leaves
above the ear. (I’ve (I ve seen as many as 12.)
However, leaves don’t don t add to forage quality, only
represent 10-12% 10 12% of whole plant yield.
(20% more leaves x 10% = 10 + 2 = 12%)
Therefore, there’s there s often less than meets the eye.
However, leafy hybrids are hot!
Why are leafy hybrids hot?
Seed price and yield
similar to non-leafy non leafy
hybrids.
The extra leaves are at
eye level, where
farmers can see them. them
Leafies simply look
great in the field.
Leafies got sex appeal!
7
9
11
In vitro true digestibility (%)
80
75
70
65
Whole plant
y = 0.83x + 73
R 2 = 0.88
Stover
1900-1929 1930-1944 1945-1959 1960-1974 1975-1989 1990-present
Relationship between corn forage in vitro true digestibility and era of
release for whole-plant and stover.
8 leaves
above the ear
Leafy corn
Normal corn
5 leaves above
the ear
Brown midrib (BMR) corn hybrids
Silage-only Silage only hybrids sold by Mycogen Seeds. Still a
tiny portion of the silage market, but increasing.
A naturally-occurring naturally occurring mutation causes incomplete
lignin formation, resulting in high stover digestibility.
Problems: Lower yield, poor standability, lousy
drought and disease tolerance, very high seed price.
Much of the benefit is from improved dry matter
intake; especially good in high corn silage diets and
for high-producing high producing cows.
cows
10
12
2