Old-Field ManagementWednesday, February 08, 2017
By Craig Harper and John Gruchy
Instead of watching deer browse the edge of a field, and instead
of waiting for deer to come to a field from a distant thicket in
the woods, why not create a field of cover and food,
full PDF here
If you ask 10 deer managers how they could increase nutrition
for deer in a field, probably nine out of 10 would say "plant a
food plot." Without question, food plots can be an important
management practice when maximizing available nutrition for
whitetails, but there are other ways to manage fields that
positively influence food and cover. Do you have a field you have
to mow every year to keep it from "growing up"? How would you like
to improve available nutrition for deer in that field without
planting anything? At the same time, how would you like to enhance
fawning and winter cover in that field? What about maintaining it
without mowing? Read on and we'll tell you how to manage an
"oldfield" - what biologists refer to as early succession habitat -
to produce benefits for deer through all seasons. It's easier than
you might think.
Field Composition and Why It's Important
Forbs - Forage and Cover
Approximately 70 percent of a deer's diet during spring and
summer is forbs. Forbs are broadleaf herbaceous plants and
represent a very important food group for deer. Many forbs are
planted, such as clovers, chicory, soybeans, and cowpeas, but most
occur naturally. Some of these naturally occurring forbs are eaten
by deer. Some are not. The trick is to identify the ones deer like
and manage the field to promote them while getting rid of the
Some of the more desirable forbs for whitetails include
pokeweed, old-field aster, beggar's-lice, Carolina geranium,
ragweed, wild strawberry, perennial sunflowers, some of the
goldenrods and many others. Don't worry if you're not an amateur
botanist. Buy a plant identification field guide. All of us can
look at a quality color picture and match it to a plant in the
field. The nutritional quality of many naturally occurring forbs
rival any plant included in your favorite food plot (see Table 1 on
page 18). The best part is they are free, and they require no
management through the growing season! Of course, nutritional
quality is influenced by plant maturity; however, most of these
plants produce new leaves from the time they germinate until they
flower. Thus, quality forage is produced throughout the growing
Not only do many forbs provide quality forage, they also provide
excellent cover. Many naturally occurring forbs are 3 to 6 feet in
height by the time most fawns are dropped in June. And unless they
are mowed down, many of these plants remain erect through winter
and provide deer a place to bed in the middle of the day, where
they can remain hidden and absorb the sun's warm rays.
Grass - Cover and Fuel
The primary component in most old-fields is grass. All grasses,
however, were not created equally. Unfortunately, many fields are
carpeted with non-native cool-season grasses, such as tall fescue
and orchardgrass, or non-native warm-season grasses, such as
bermudagrass. These grasses are most undesirable as they offer
poor-quality forage and cover for deer, and they displace
preferable plants and inhibit the seedbank from germinating.
Yes, we have all found fawns in a tall fescue field that wasn't
hayed in June, and we have seen deer eating orchardgrass. We have
also seen human beings eating out of trashcans and sleeping on the
sidewalk. The point is, what we observe is not necessarily the way
things should be. Sometimes animals, like humans, eat certain
things and use certain habitats because nothing else is available.
If the fawns on your property are forced to bed in tall fescue
fields and the adult deer are limited to eating orchardgrass, rest
assured that is an indication of overall poor-quality habitat.
Without question, you can do much to improve the quality of cover
and available nutrition just by getting rid of these grasses and
allowing the seedbank to respond!
Desirable grasses in old-fields include several species of
native warm-season grasses (NWSG), specifically big and little
bluestem, broomsedge bluestem, indiangrass, switchgrass, and
eastern gamagrass. These grasses are preferable to the nonnative
grasses mentioned above because NWSG provide better fawning cover
and winter cover. NWSG are not, however, promoted for food. Deer
eat very little grass of any kind during the summer. In winter,
while non-native grasses provide virtually no cover whatsoever,
NWSG can provide deer with outstanding winter cover, especially if
there is a desirable forb component growing with the grasses that
helps provide structure.
Cover is not the only benefit of NWSG in an old-field. When it
comes time to manage the field, grass cover is essential to carry
prescribed fire. Without grass, it can be quite difficult to burn a
field because of a lack of fine fuels near the ground. Without fine
fuels to carry the fire, excessive wind is needed to burn a field
of forbs, which typically have only a single stem from the ground
up to 2 feet or more where the dead foliage occurs. As we'll cover
later, fire is an integral component in oldfield management.
Shrubs and Brambles - Don't Fear Them!
Do you look at a field that contains shrubs and brambles and
cringe? If so, you need to put on your rose-colored glasses. These
are some of the most important plants in the field! Sumac,
blackberry, wild plum, elderberry, crabapples, hawthorn - all of
these and others provide an excellent source of food and cover
within old-fields. Unfortunately, the brushy appearance of these
species in an old-field often gets them "bushhogged" before they
can provide any benefit.
To enable an old-field to provide maximum benefit for deer, it
is absolutely critical that you allow forbs, grasses, and shrubs
and brambles to develop. A field of pure NWSG may provide cover,
but its overall value for deer is far less than an old-field with
more diverse vegetation.
Field Renovation Get Rid of the Carpet
Your first step in enhancing an old-field is to eradicate the
non-native grasses. We like to call this "removing the carpet."
Why? Because cool-season grasses and bermudagrass form a mat over
the field that inhibits the seedbank from germinating. When this
carpet is removed, seeds in the top few inches of soil are able to
germinate, and desirable plants can be promoted. This is where your
forbs come from. We think it is analogous to removing an ugly shag
carpet in an old house and finding a beautiful hardwood floor
It is important
to note that while deer are selective in what they eat, plants are
not necessarily eaten based on nutritional content. While pokeweed,
old-field aster, and prickly lettuce were browsed heavily,
blackberry, partridge pea, beggar's-lice, ragweed, goldenrod, and
3-seeded mercury were only browsed moderately. Japanese
honeysuckle, a highly preferred deer forage in many southern
locations, had a low preference value in this study. For other
species, such as passion flower and sericea lespedeza, there was no
sign of browsing at all, even though crude protein and
digestibility ratings were high. Deer density in this area was
approximately 25 per square mile and quality forage was not lacking
as there were plenty of soybean fields as well as warm- and
cool-season food plots on the farm. Also shown is the estimated
value of these plants for wild turkeys and bobwhite quail.
The only way to get rid of the carpet is by spraying the
appropriate herbicide. Moldboard plowing will not eradicate problem
grasses, such as tall fescue, orchardgrass, bermudagrass and
johnsongrass. Within two years, they will be back. Different
grasses require different herbicides and different spraying
techniques. Regardless, before spraying, it is critical to prepare
the field for spraying by burning or haying. You must spray
actively growing grass, and you don't want dead leaves and stems to
block the herbicide from coming in contact with the target
The first step in
renovating an old-field for deer and other wildlife is to eradicate
the non-native grasses, such as tall fescue and orchardgrass
(inset). These grasses are extremely low preference forages for
deer and provide no cover during winter. Further, these grasses act
as a carpet over the field, smothering the seedbank and inhibiting
more desirable plants from germinating.
To get rid of perennial cool-season
grasses, prepare the field for spraying by burning or haying in
September (August if you are in the North). After burning, the
cool-season grasses will grow with a vengeance. Allow the grasses
to grow 6 to 10 inches, then spray with a glyphosate herbicide.
Spraying in the fall is recommended because a better kill is
realized versus spraying in the spring and also because desirable
NWSG and forbs are not harmed by fall spraying.
Fall is the best
time to spray perennial cool-season grasses. Before spraying, it is
essential to prepare the field by haying or burning to encourage
fresh grass growth and remove dead plant material that will block
To eradicate non-native warm-season grasses, spray in the
summer. Spray bermudagrass with Arsenal in late June, about the
time bermudagrass begins to flower. Spray johnsongrass with a
glyphosate herbicide when it reaches about 18 inches in height. If
johnsongrass is growing among desired plants, such as broomsedge or
blackberry, use an imazapic-based herbicide, such as Plateau, and
you will not harm many desirable plants.
Patience is a virtue, and this is certainly true when renovating
old-fields for wildlife. Even if you sprayed problem grasses
exactly as recommended, there will usually be some residual growth
the following year. This is not a problem - just spot spray as
needed. Rome wasn't built in day, and your old-field is not going
to provide perfect habitat overnight. It will take two to three
years to develop.
Once you have gotten rid of the carpet, you must wait and see
what the seedbank contains. Often, desirable plants recolonize the
site quickly. But sometimes, one non-native problem is followed by
another. For example, it is not uncommon to eradicate one carpet of
tall fescue only to find another carpet of bermudagrass or
johnsongrass lying underneath. Or, problem forbs such as sericea
lespedeza or thistles might arise. That's OK - don't be
discouraged! It just means you have some more spraying to do. With
persistence, you will get rid of all the old carpet layers and
stimulate the plant community you are looking for. This will not
happen, however, unless you diligently eradicate the invasive
nonnative plants that suppress the desirable plants.
Do You Need to Plant?
We hardly ever recommend anyone plant NWSG and associated forbs
until they have waited at least one to two years after killing the
non-native grass cover. As soon as the non-native cover is killed,
there will be plants germinating from the seedbank. Most of these
will be annuals. The perennial plants will increase over the next
two years. Remember, these plants have been smothered by a carpet
for many years, just waiting for a chance to germinate. Often, it
takes time to develop the plant community you want.
There is no need
to plant if the seedbank already contains desirable species. This
field was a tall fescue hayfield. Once the carpet was removed, the
native seedbank flourished. Now, there is broomsedge bluestem,
switchgrass, and eastern gamagrass throughout the field, along with
blackberry, ragweed, beggar's-lice, and many others, providing
excellent fawning cover, forage, and winter cover. Note: the photo
on the left was taken in July; on the right, November.
Nonetheless, if desirable plants are not present during the
second year after eradicating the non-native grasses, it is time to
think about planting the following spring. A wide variety of native
grass and forb seed is available from several suppliers. When
managing the field for deer is the main objective, we recommend
planting 5 to 6 pounds of native grasses with at least 1 to 2
pounds of forbs, per acre (a suggested mixture is shown here). Be
sure to use varieties of NWSG indigenous or adapted to your area.
And remember the desirable forbs and shrubs we mentioned
Fertilization - Is It Necessary?
Plants native to a particular area generally do not require
fertilization to grow. However, just as with your food plots,
fertilizing old-fields will stimulate additional plant growth,
increase palatability, and provide more nutrition for deer. In
areas with poor soils, fertilization may also enable plants to
provide better cover. Nutrient-deficient grasses and forbs
typically do not grow as tall and robust as those on better sites.
On relatively poor sites, add 30 to 60 lbs./acre of nitrogen in
late April/early May and make sure 50 to 100 lbs./acre of
phosphorus and 200 to 250 lbs./acre of potash are available. Of
course, you won't know nutrient availability unless you have soil
samples tested. It is also important to realize the benefits of
fertilization are much reduced unless you have adjusted pH to 6.0
Composition and Management
Plant composition within the field is influenced by management.
We like to maintain approximately 50 percent grass cover intermixed
with 50 percent forb cover with patches of shrubs and brambles
scattered throughout the field (no more than 100 yards apart).
After four to five years, grass coverage may increase. When grass
coverage exceeds 70 percent, we balance the composition by disking
in February/March or burning in September. In the meantime, we
maintain desirable plant composition by burning every two to four
years in late winter/early spring, and control any problem plants
that arise by spot spraying, usually in the spring.
Using prescribed fire is by far the single-best management
practice for maintaining early succession communities. Burning
consumes dead plant material, and nutrients from the ashes are then
moved via rainfall into the top couple inches of soil. This
typically increases plant nutrition the following growing season.
As dead plant material is consumed, an open structure is created at
the ground level. This allows the seedbank to germinate and creates
optimum conditions for brooding wild turkeys and bobwhites as they
are able to pick up seeds and bugs under a protective canopy of
be maintained with prescribed fire. Burning sets back succession,
recycles nutrients, consumes dead vegetation and stimulates the
seedbank. Season of burning and frequency of burning influence
plant composition. Here, we are rejuvenating our native grasses and
reducing a few undesirable plants by burning in the early growing
season (April). Burning is much more efficient and effective when
managing early succession habitats than mowing.
When maintaining the existing composition in the mid-South, we
burn from mid-March through mid-April. This does not destroy winter
cover until the onset of spring and does not negatively influence
nesting. We do not recommend burning all cover in one year. If you
only have one or two fields, split each field in half with a
firebreak and manage the sections on a different rotation. If you
have several fields, you may burn entire fields on a different
it is imperative to establish safe firebreaks around the field.
Firebreaks can be planted in various food plot plantings adjacent
to quality cover. Here, oats are providing quality forage in
February in a firebreak that was well positioned outside the
dripline of the trees to allow a soft edge to develop between the
woods (left) and the field (far right).
Burning can also be used to reduce woody cover. If undesirable
woody species (such as sweetgum, red maple, winged elm and green
ash) begin to encroach into the field, burn the field in
September/early October, before the leaves begin to turn color.
Burning at this time effectively kills the tree by severing the
cambium layer inside the bark and preventing the flow of
carbohydrates down to the root system. If you burn these saplings
in the dormant season, you will find three sprouts where there was
one! Protect your blackberry patches, wild plum thickets, and sumac
stands from fire (unless you want to decrease their coverage) by
disking around them, which provides other benefits.
When grass density approaches 70 percent, we increase forb
coverage by disking strips 50- to 100-feet wide, evenly distributed
across the field. In succeeding years, we rotate disked strips to
maintain the overall composition within the field. Rotating these
strips is very important to maintain desirable forage plants for
deer (see the chart at left). Ideally, disking should be conducted
in February in the Deep South and March in the mid-South and the
North. Disking at this time enables cover to stand through winter
and promotes more favorable forbs.
Disking later into spring may stimulate undesirable species,
such as johnsongrass, crabgrass, and sicklepod. Disking is also
used to maintain firebreaks. If you are going to burn, it is
necessary to create firebreaks one to two tractor-widths wide to
keep fire from spreading outside the field. To make things more fun
and provide additional nutrition, we plant our firebreaks as food
plots. We like to keep some sections in warm-season forages and
grain and others in cool-season forages. This way, we have an ample
supply of quality forage around the field, even during winter,
adjacent to a fantastic cover source. Like to bowhunt? We position
our firebreaks approximately 50 feet from the woods edge to reduce
competition for sunlight and nutrients and allow a soft edge of
brush to develop around the field, which provides a perfect bow
shot for deer feeding along the firebreak. This technique also
allows you to hunt in more than one wind direction.
We consider mowing the least desirable management technique for
maintaining old-fields and recommend against it if at all possible.
Some folks promote mowing, especially during the growing season,
because they feel it stimulates additional growth and increases
nutritive value of plants. This is true for grasses, but grasses
are not an important food item for deer during the summer. Mowing
during the summer increases grass dominance and decreases forb
coverage. The exception to this is perennial clovers, which respond
well when mowed or grazed. We are not concerned with clovers in our
oldfields, however, because we manage for clovers in our food plots
and firebreaks. We are more concerned with providing quality cover
and structure in our old-fields. The forbs we are promoting in our
old-fields provide cover and forage.
Mowing accumulates debris at the ground layer and suppresses the
seedbank. Further, mowing during the growing season not only
destroys fawning and nesting cover but often destroys fawns and
nests. Nonetheless, some managers are prevented from burning by
regulation or narrow windows of opportunity based on climate. If
you cannot burn or disk, then mow in late winter, just prior to
spring green-up. This allows deer the opportunity to use the cover
through the winter and does not destroy fawning or nesting cover
during spring and summer.
We often ask quail and rabbit hunters why they always hunt
around the edges of fields. The answer is obvious - that's where
the quail and rabbits are. But why? Because that's where cover for
quail and rabbits exist. Why is this? Because the composition and
structure of the field differs from that along the edge. Why?
Because the field is not managed correctly for quail and rabbits.
We ask, why not create a "field of edge"? That way, you will jump
as many quail and rabbits from the middle of the field as you do
around the edge! The same principle applies to deer. Instead of
watching deer eat forbs and browse around the edge of the field and
instead of waiting for deer to come to a field from a distant
thicket in the woods, why not create a field of cover and food,
naturally? Why not increase the amount of usable space on your
property and enable your property to carry more deer? We think you
will enjoy your efforts, and the deer and other wildlife will
This field on the
Mayfield Farm in McMinn County, Tenn., shows the perfect plant
composition when managing old-field habitats for deer and other
species of wildlife. Native grasses, forbs and scattered shrubs,
providing both food and cover. This is a Leopold Landscape!