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GRASSES

Grasses are the workhorse family of the cover crop world, Sorghum Traits
generally producing the highest yields and greatest bio- Brown Midrib (BMR) is a natural-
mass. Grasses comprise the bulk of many mixes, including ly occurring mutation that makes
most grazing mixes, and are generally very palatable for plants less able to produce indigestible
livestock. Grass plants tend to be higher in carbon to ni- lignin, which give them higher digest-
trogen ratio and can provide excellent residue if allowed ibility and far better (usually about
to go to maturity. 30% better) animal performance than

Sorghums non-brown midrib varieties of similar
genetics. If a sorghum is to be used for
There is no more versatile and widely used family of cover animal feed, a BMR is preferable.
crop species then sorghum and its array of relatives. There Brachytic Dwarf (BD) is a trait that shortens the inter-
are many purposes for which sorghum plants are suited, nodes on a plant, but actually increases the total number of
and different types and traits have been developed to meet leaves on a plant. This results in a leafy, short-statured plant
these needs. with low-set growing points that tends to stand better later

Sorghum Types in the season.
Sudangrass is a fine-stemmed sorghum that regrows rapid- Dry-stalk (DS) is a trait in which the pith of the plant
ly after defoliation. It is earlier maturing and lower yielding has less water content than most hybrids, meaning it can
than other sorghum types if all are allowed to grow to full dry out faster in a swath than other hybrids of similar
maturity. It has a lower sugar content than other sorghums, stem diameter.
but is higher in protein and palatability. Sudangrass is lower Photoperiod Sensitivity (PPS) prevents the sorghum plant
in prussic acid potential than other sorghum types. from heading out until the day length drops below 12 hours
Forage Sorghums are coarse-stemmed, long maturity sor- and 20 minutes, which for most areas will be mid-Septem-
ghums that are higher in sugar and historically used as a ber. Heading is undesirable in a plant used for forage, unless
source of syrup. Today they are used as breeding stock for the plant is intended for silage. Four things happen when a
many modern hybrids to enhance sugar, growth, and palat- plant heads out and they are all bad for forage production:
ability. They have poor regrowth but high yield potential if first, leaf production stops; second, root growth stops; third,
allowed to grow to maturity. the amount of lignin goes up and the plant becomes less di-
gestible; and fourth, water use goes up from 30% to 50%. By
delaying heading, a PPS hybrid will be very high-yielding,
retain forage quality for longer periods of time, and be very
water efficient.

Delayed Maturity (DM) is similar to photoperiod sensi-
tivity but does not depend on day length to function, but
rather a large amount of heat units.

Male Sterile (MS) hybrids have pollen that is not fertile,
and thus cannot self-pollinate, and will not produce seed
unless pollinated by another sorghum. MS hybrids are a
great choice to prevent any chance of volunteer seedlings
the next year but need to be isolated from other sorghums
(including Johnsongrass) for a quarter mile to prevent
Sorghum-sudans are hy- seed production.
brids between sudangrass and
forage sorghum. They are in- Best Sorghum Traits for the Situation
termediate in most character- Summer Grazing: Rapid regrowth and low-set growing
istics but also exhibit hybrid points (for grazing tolerance), as well as a very high leaf-
vigor, and thus have excellent to-stem ratio, and high digestibility. Look for a BMR, BD
yield and regrowth potential. sorghum-sudan.

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