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| Most Imperial perennial blends fix nitrogen, which can reduce fertilizer costs for rotational crops. |
Whitetail
Institute forage products are designed to establish and grow quickly and
perform at the highest level. Here are some tips to help you keep your soil in
the best possible condition so that your plantings can grow as well as they
should — and help you save money in the process.
HAVE
YOUR SOIL TESTED BY A QUALIFIED SOIL-TESTING LABORATORY, AND FOLLOW THE LAB’S
RECOMMENDATIONS ON LIME AND FERTILIZER
That’s your
first tip, and it’s the biggest one. And to regular readers of Whitetail News,
that comes as no surprise; almost every issue has a reminder somewhere about
how important soil testing is, both to forage performance and to help you save
money.
Two important
things your soil test report will tell you are the existing soil pH of the soil
in your plot and how much lime you’ll need to add to the soil to raise soil pH
if it is low. Most high-quality forage plantings will have a hard time growing
as well as they otherwise could unless soil pH is “neutral” (in a range from
about 6.5-7.5) because neutral soil pH is where they can best uptake nutrients
from the soil.
If soil pH is
low, it should be raised before planting by disking or tilling lime into the
soil. To see why this is so important, think of plants taking in nutrients from
the soil as humans eating food from a refrigerator. We humans can only take in
the food we need if two things are true: the food must be in the refrigerator,
and we must have access to the refrigerator. Even if the food is there, it does
us no good if we can’t open the refrigerator door. The same is true of plants.
The nutrients they need must be there in the soil, either naturally or by
applied fertilizer, and the plants must be able to uptake (access) those
nutrients. Soil pH affects the ability of plants to uptake nutrients from the
soil. If soil pH is below neutral, forage plants are not able to uptake
nutrients (open the refrigerator door) as freely, and the lower soil pH is, the
harder it is for them to do so.
Whitetail
Institute forage products come with lime and fertilizer recommendations on the
back of the product bags. These are generalized recommendations for situations
in which a soil test isn’t available, and they’ll cover most situations.
However, they won’t be exact for everyone because precise lime and fertilizer
recommendations depend on factors unique to each site, such as soil type,
existing soil pH and existing nutrient levels.
Taking these
factors into account with precision requires physically testing a sample of the
soil from the plot in a qualified soil-testing laboratory. That’s why only a
qualified soil-testing laboratory can provide lime and fertilizer recommendations
that are sufficiently precise to help you maximize forage production and, at
the same time, eliminate wasted lime and fertilizer expenses. High-quality soil
test kits are available from the Whitetail Institute, County Agents,
agricultural universities and many farm supply stores.
CROP
ROTATIONS
Crop rotation
is a best-management practice. It makes economic and agronomic sense, and
offers the opportunity to improve soil structure, break insect and disease
cycles, control problem weeds and improve yields.
Any soil that
is asked to grow the same crop year after year, whatever the crop, eventually
may require a break. After removing the existing crop, it may help rejuvenate
the soil in some cases by planting entirely different forage types in the site
for a growing season (“rotating” out of the old crop and into one that’s
totally different). Crop rotation is usually not as big a deal to food
plotters, at least not as big as it is with commercial farmers who repeatedly
plant the same crop in the same site. With food plotters, it’s occasionally an
issue with perennial forages that have been growing in a site for years. Also,
most Whitetail Institute forage products are blends of different forage types,
reducing the chance of a crop rotation being needed even further. But brassica
and alfalfa bear special mention, so I’ll cover them separately in a moment.
When is crop
rotation necessary? Determining if and when a crop rotation is needed is
usually fairly simple. Basically, you notice that despite having planted and
maintained the forage according to directions, it’s just not growing as well as
it should and has in the past. If you see that, then perform the two-step
diagnosis I’ll set out below.
Notice that I
said “despite having planted and maintained the forage according to
directions.” One critical thing that means is that soil pH is, or has been
raised to, at least 6.5. If soil pH is low, then the forage can struggle. Determining
that crop rotation is necessary presupposes that soil pH is in optimum range:
6.5-7.5 (“neutral” soil pH).
The main reason
a crop rotation may be necessary is the buildup of disease organisms over time.
Diagnosis is usually pretty straightforward. There are two steps.
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| Imperial perennials such as Alfa-Rack Plus contain diverse components, which can help keep soil fresh. |
Step 1: Pull up some of the
plants, and look at the roots. The roots should be firm and healthy looking. If
they are soft, spindly or weak looking, there’s a good chance that the soil has
a build up of root-rot organisms like fungus, which can cause poor crop yield
or even complete failure.
Step 2: While you’re digging around in the
soil, look for root-eating insects and their larvae, which can also build up
over time. Either of these also indicates that it may be time to rotate.
Rotational
Crops. When deciding what to plant as a rotational crop, select plant types
that are different from those you had growing in the site. Any Whitetail
Institute fall/winter annual is a good rotational crop after Imperial Whitetail
Clover, Chicory Plus, Alfa-Rack Plus or Double Cross. If you had Tall Tine
Tubers or Winter-Greens growing in the site during the fall and winter, you
might consider rotating into PowerPlant the following spring and summer. The
key is that the plant types in the rotational crop should be different from
those in the existing crop.
Brassica: Each situation is different, but
due to unique characteristics of brassicas it’s generally recommended that you
not plant brassica back-toback in the same site for more than a year or two in
a row without a break. The issue can be substantially reduced, though, if the
seedbed is correctly prepared prior to planting, including ground tillage, and
if tillage is started several months before replanting. To clean the soil as
quickly as possible following a brassica crop, though, plant the site in a
completely different type of annual during the spring and summer. As I
mentioned, PowerPlant is an excellent choice. Plan ahead with plot locations so
that you can move your Winter-Greens and Tall Tine Tuber plots every year or
two.
Alfalfa: Alfalfa’s
auto-toxicity property can inhibit the growth of a new alfalfa crop planted
immediately after an existing alfalfa stand in the same site. With Alfa-Rack
Plus being a blend of various species, though, that’s usually not as likely to
be an issue, so you can diagnose the need for crop rotation just as you would
for any other forage.
NITROGEN
FIXERS CAN REDUCE FERTILIZER COSTS FOR ROTATIONAL CROPS
Farmers
commonly rotate long-term grain fields out of production and into clovers and
other nitrogen fixers for a while before returning them to grain production.
This can help improve soil quality, protect soil from excess nutrient depletion
and reduce nitrogen fertilizer expenses. If you have had one of the Whitetail
Institute’s perennial nitrogen-fixing products (Imperial Whitetail Clover,
Chicory Plus, Double-Cross or Alfa-Rack Plus) growing in the same site for
years and determine that it’s time to rotate the site into a Whitetail
Institute annual for a season, take advantage of the nitrogen that has
accumulated by tilling under the existing crop and planting Pure Attraction,
Winter-Greens, Tall Tine Tubers or Whitetail Forage Oats Plus and you will be
utilizing the valuable nitrogen that is in your soil, creating a disease break
and saving money on fertilizer.
