DROUGHT – FORAGE ISSUES
Garry Lacefield, Ray Smith, and Tom Keene
Plant & Soil Science Department
University of Kentucky
Forages 2007 WOW!!! What a year. Our hay feeding season ended with the
lowest “hay carryover” in recent memory. Optimism was high with an early growth of 46 weeks of abnormally warm weather and very good forage growth. Things were going
great with some alfalfa plants exceeding two feet in height – AND THEN, the Easter
weekend with “record setting” low temperatures across the state. The freeze resulted in
major damage to our taller growing legumes and some new seedings, less damage was
observed on our cool season grasses – AND THEN, three consecutive months of below
normal rainfall. April through mid-June was the driest in Kentucky history.
IMPACT –
Low hay carryover, freeze, and drought has resulted in very short forage supplies.
Spring haymaking was only about 50% of normal.
OPTIONS –
Rains in late June and early July have certainly helped with pasture; however, we
are still very short on feed and need to consider all options and re-evaluate some options
that may have not been that economical in the past.
STRATEGY –
1.
Inventory – What are our needs now and this winter? What is our present
pasture hay, silage situation? Knowing demand and supply will get us
started on the inventory.
2.
Effective USE – This year more than ever we MUST use our pasture and
hay efficiently (reduce waste). Grazing methods like rotational grazing
and strip grazing can stretch a short pasture supply (see Rotational
Grazing ID-143). In addition, make plans to evaluate and test hay to know
the feeding value and match quality to animal needs at feeding. Always
feed hay using feeding techniques that will reduce LOSSES.
3.
Make plans for more feed – Depending on late summer – fall moisture, we
can grow a lot of feed before winter. In addition, we are hoping for a mild
winter which will permit us to graze longer, reducing the need for hay and
silage.
STOCKPILING –
Stockpiling has been our best, most consistent, way of producing fall and early
winter pasture. As hay prices increase, this option, even with high nitrogen, should be
considered (see Stockpiling for Fall and Winter Pasture AGR-162).
Table 1. Yield and crude protein content of Kentucky bluegrass and
tall fescue produced from Aug. 15 to Dec. 1 under different levels of
N fertilization at Lexington (average of three years).
Nitrogen
Bluegrass
Fescue
Applied
Yield
%
Yield
%
lb/acre
lb/acre
Protein
lb/acre
Protein
0
700
12.8
1700
11.1
45
1600
15.5
2800
11.8
90
2100
19.1
3900
14.8
Source: Taylor, T.H., and Templeton, Jr., W.C. 1976. Agron. J. Vol. 68, Mar-Apr.
Table 2. Effect of time of nitrogen
application on production efficiency of KY 31
tall fescue.
Date N
Nitrogen Efficiency
Applied
Lb DM*/lb N added
Aug 1
27.2
Aug 15
25.8
Sep 1
19.2
Oct 1
10.8
*Dry matter.
Source: Murdock, Lloyd W. 1982. Agronomy Notes.
Vol. 15, No. 2, April 1982.
Table 3. Seasonal percentage changes in chemical
composition and digestibility of tall fescue.
Spring
Summer
Fall
Sugars
9.5
8.5
19
Protein
22
18
19
D.D.M.*
69
66
74
*Digestible dry matter.
Source: Buckner, R.C. 1975. Univ. of Ky. Coop. Ext. AGR-44.
Table 4. Performance of dry, pregnant cows* grazing
stockpiled tall fescue (four-year average).
Grazing dates
11/6 to 2/10
Average daily gain
1.24 pounds
Stockpiling rate
1.33 cows per acre
Gain per cow
119 pounds
Hay fed per cow (11/6 to 2/10)
564
*Mature Angus cows bred to calve in March.
Source: Bradley, Neil, et al. 1984 Beef Cattle Research Report, University
of Kentucky College of Agriculture Progress Report 282, pp. 11-12.
Table 5. Wintering cost per cow. Winter feeding period from Dec. 1 to Apr. 10.
Stockpiled Tall
Ryegrass +
Forage Source
Hay
Cornstalks
Fescue
Cereal Rye
$/cow/day
$1.32
$0.05
$0.31
$0.61
Days of use
130 hay
60 stalks
90 graze
90 graze
70 hay
40 hay
40 hay
Wintering cost
$172
$122
$70
$108
Source: Gerrish, J. et.al., University of Missouri
CROP RESIDUES –
Residue left following grain crop harvest (especially corn) can provide a source of
feed although quality is not high.
Crop residues vary considerably in both quality and quantity which would be
available for cattle. Table 6 lists some of the common residues as well as the quantity
and quality you may expect to have in the field.
Although residues from corn, soybeans and sorghum may be used, the major
source of crop residue in Kentucky is from the corn crop following grain harvest. The
corn plant has over 50 percent of its weight in stalks, leaves, shucks, and cobs.
Considerable grain may also remain in the field after combining. Even with conservative
combining techniques 4 to 6 bushels per acre may remain. A crop with a 100 bushel
grain yield will normally yield from 2-3 tons or residue. Assuming only 25 percent
utilization, this dry matter residue can provide 80-100 grazing days. With this large
amount of dry matter potentially available, careful considerations should be given to
methods of feeding.
Table 6. Approximate Feed Value and Yield of Refuse Materials.
Yield/A
Dry Matter Crude Protein
Material
(tons)
%
%
Husklage
Illinois
1.0
55
6.0
Iowa
1.1
67
4.0
Stalklage
Illinois
6.0
47
10.0
Iowa
3.0
52
4.4
Purdue
2.8
--6.0
15-20
35
3.0
Corn Silage
2-3
87
5.0
Corn Stover
--90
2.8
Corn Cobs
--90
5.0
Soybean Stover
2-3
85
4.5
Sorghum Stover
TDN
%
--35
------22
50
47
40
49
Source: Salvage Feeds for Beef Cattle, ID-9, University of Kentucky.
Feeding methods may range from “whole field” grazing, to restricted grazing, to
mechanized harvesting and feeding. Obviously restricting animals or machine harvesting
will probably require more labor and equipment than “whole field” grazing, but less feed
will be wasted. Use the method which best suits your particular farm. For example, if
you have small fields, you may want to graze them one at a time. If you have large
fields, you may want to strip graze in order to get more complete utilization of the feed.
Grazing
Permitting animals to graze stalk fields is the most common way of harvesting
since it is usually the cheapest and requires less labor and equipment. Whole field
grazing limits the degree of utilization, as animals waste a large amount of the residues
available through selective grazing, trampling, and overconsumption. Restricted grazing
through the use of a temporary electric fence will result in more complete utilization.
Allowing animals access to only a two to three week feed supply will force animals to
utilize a larger amount of the dry matter thus wasting less.
Another grazing technique which can be used effectively is to allow those animals
with the higher nutrient demands (such as young growing animals) to have first access to
a stalk field. Follow them with dry cows. This system allows the better quality materials
to be selected by the first grazers and forces the lower nutrient requiring dry cows to
clean up the remains. Caution: (1) There have been cases where too much grain left in
the field resulted in animals overeating and foundering. (2) Prussic acid poisoning has
been reported when grazing fields that were infested with Johnsongrass. This problem is
greatest during the early frost period. (3) Abide by all grazing restrictions from
herbicides used on the crop. Most corn herbicides used in Kentucky permit grazing while
most soybean herbicides place some restrictions on grazing residue. Read and follow all
label directions.
Strip grazing will result in more efficient utilization and increase grazing days per
acre.
NEW SEEDINGS
We are receiving many questions about what can be seeded to provide late
summer and fall grazing and hay. The first answer is that there are no “easy solution” to
the feed shortage created by the drought and the late freeze. There are a number of
options though, which are outlined in the following paragraphs including links to more
detailed publications. Remember that now may be a time to “start over” on some pastures
and hayfields, and fall is an ideal time to reestablish perennial cool season stands.
Establishment Method
It is tempting to try to seed directly into existing pastures and hay fields especially
with annual crops. While this approach is sometimes successful, all too often the
competition of the well rooted perennial sod limits grow of the newly seeded forage.
Seeding directly into existing stands is only recommended when stands are thin or
severely weakened.
In general, planting into a conventionally tilled seedbed is more effective than notill seedings. Planting depth for small grains is 1 to 2 inches, but it is essential that
perennial forage grass and legume seed not be planted deeper than ¼ to ½ inches.
Planting too deep is one of the most common reasons for stand failure.
No-till seeding can be successful and is often preferred on sloping land. No-till
establishment works best into crop stubble, but will also work into existing sod as long as
the existing vegetation is killed or suppressed. Existing stands can be suppressed by close
grazing or herbicides. Suppression rates range from 1 to 1 ½ pints per acre of glyphosate
(at 3 lb ai/gal) or Gramoxone. Kill rates range from 3 to 6 pints/acre glyphosate (at 3 lb
ai/gal) and should be applied 3 to 4 weeks before overseeding. Ideally, two sequential
applications (4 to 6 weeks apart) of glyphosate are preferred for a complete kill.
Surface broadcast seeding is only recommended for red and white clover seeded
during February (frost seeding) onto a closely grazed or clipped sod. Broadcast seeding
rarely work in the late summer with exception of annual ryegrass, and even with ryegrass
drilling is preferred. The recently updated UK publication “Grain and Forage Crop Guide
for Kentucky, AGR-18” provides seeding rate and other establishment details for all
forage and grain crops that can be grown in Kentucky.
Small Grains
Late summer seeded small grains provide fall grazing, late winter/early spring
grazing, and a hay or silage harvest next spring. There are a number of small grain
options which include: wheat, cereal rye, spring and winter oats, barley and triticale.
Below are a few advantages and disadvantages of wheat, rye and oats and basic
management guidelines. Remember that all most small grains require a cold period
before they will produce a seedhead (spring oats are the main exception). Therefore, late
summer and fall plantings will remain vegetative (only leaf growth) and continue to
regrow after grazing in the fall and early spring. For more management information or
details on other small grains see “Managing Small Grains for Livestock Forage, AGR160.”
Cereal rye provides rapid grown for fall grazing and more fall growth than wheat.
It is also has early spring growth, but is lower quality than wheat as it matures. Wheat
provides a high quality grazing and hay/silage crop, and seed is plentiful and cheap. Oats
are also an option, but remember there are two types of oats. Winter oats are planted in
the fall and mature with seedheads next spring, but most varieties have marginal winter
survival in Kentucky. Spring oats show good growth after seeding and heads out in the
fall and then winterkills after freezing temperatures. In recent years, some producers in
Ohio have reported good fall cut hay yields from spring oats. This is an option worth
considering this season with hay supplies low and prices high. Spring oats can also be
grazed, but will not regrow after grazing once seedhead start to elongate.
The recommended planting date for small grains is mid-August to early
September when grazing in the fall or when growing spring oats for hay or late grazing.
Poor pasture growth and hay shortages have encouraging even earlier seedings this year.
Some reports show that oats can be successfully seeded in late July/early August, but the
advantages of early seeding may be negated by high August temperatures and low
rainfall. The use of “bin run” seed may be preferred with early seeding since the risk of
stand failure due to low moisture and high temperatures is greater.
TAKE NOTE:
1) Planting should be delayed until late September and October when growing small
grains for grain, hay or silage since excess unutilized fall growth limits yield.
2) Remember that crabgrass can provide excessive competitive with earlier seedings.
This is one of the reasons that perennial grass establishment is often most in early
to mid-September once nights are cooler and the growth of weedy grasses slows
down.
3) Remember if wheat is planted earlier than October 1 it has a high risk of being
infected with Hessian fly larvae. Vegetative or leaf growth continues, but most
seedheads do not develop the following spring severely reducing hay or silage
yield.
Annual Ryegrass
Annual ryegrass is a good option for late fall and spring grazing with relatively
fast growth after seeding (not as fast as rye or wheat), good regrowth, and high quality.
Make sure to choose an annual ryegrass variety that has proven winterhardiness in
Kentucky. For more detailed information see “Annual Ryegrass AGR-179.”
Summer Annuals
We are now past the date when summer annuals like sorghum-sudan and
sudangrass should be planted. Not only are seed supplies short this summer, but the
amount of growth that can be expected is more and more limited with each day that
passes. The only possible exception is German (Foxtail) millet which produces a one cut
hay crop in 60 days.
Late Planted Corn
Some producers are considering planting corn as an emergency grazing crop. This
is not something we would normally recommend, but planting bin run corn through a
grain drill may be an option given the feed shortages we are experiencing. Remember
though that the growing point of corn will be above the ground within 3 weeks of
planting and once the growing point is removed it will not regrow. Therefore, corn is
really only an option as a quick growing, one grazing emergency feed. A major limitation
to planting corn or other summer annuals is that you have taken a field out of production
that could be used to plant small grains for grazing through the fall and next spring. We
are even less optimistic about soybeans in this situation.
Brassicas
During the last few years there has been a resurgence of interest in planting
brassica crops like turnips. These can be seeded in August at low seeding rates (3 to 6
lb/acre) and produce very high quality feed for fall grazing. They are used for fall and
early winter grazing because they rarely survive Kentucky winters. The traditional variety
Purple Top is cheap to buy, but we recommend newer varieties that produce more leaf
growth and smaller bulbs. Is it quite common for them to be planted with spring oats, rye,
and annual ryegrass to add fiber and yield to the highly digestible brassica. The
advantage of including rye, wheat and annual ryegrass is the spring regrowth of these
forages. In Illinois producers like to use 1½ bu oats, 1 bu rye, and 4 lb/acre brassica.
Another option is 3 bu oats and 4 lb/acre brassica. With annual ryegrass a common
seeding rate is 30 lb annual ryegrass with 4 lb/acre brassica.
HAY
Hay producers in Kentucky have been hit with 2 major setbacks during the early
part of the 2007 hay making season. First, there were the freezing temperatures that first
week in April right before Easter. Temperatures dipped to the upper teens around the
state on two separate nights freezing back new plant growth that had occurred during a
record warm March. Frozen plant material losses of between ½ a ton and 1 ½ tons per
acre seemed to be the norm. Several cool, cloudy, damp days followed the freeze,
holding back plant growth even more. Once regrowth started, most stands made a decent
recovery (although alfalfa struggled to out compete the weevils). However, that’s when
Mother Nature decided to turn off the water and that brings us to our second
setback….extremely dry months of May and June.
Livestock producers do have some tools however to deal with these reductions in
hay yields. First, we need to do a much better job of storing the hay we were able to
make. Storage losses in Kentucky can run up to 50 % during a normal year when round
bales are just stored outside along the fence line. If inside storage is not available,
covering the bales, elevating them off ground, etc… will help reduce storage losses and
no one can afford storage losses this year. Anything that we can do to reduce those
storage losses will make our hay go further.
Table 7. Effect of feeding systems on losses of Johnsongrass hay and on steer
performance.
Conventional bales
Round bales
Round bales with
Item
on sod
on sod
panels
Hay fed, lb/day
9.1
19.1
12.3
Days on test
79
79
79
Initial wt. (lb)
535
538
538
Final wt. (lb)
615
635
646
Gain/animal
80
97
108
Average daily gain (lb)
1.0
1.2
1.4
Lb hay required/lb of gain
Adapted from: W.B. Anthony, E.S. Renoll, and J.L. Stallings. 1975. Alabama Agric. Exp. Stn. Cir. 216.
(also see Minimizing Losses in Hay Storage and Feeding on our Forage Website)
The hay that was made during May and early June was good quality for most part
since there was little rain damage. With the quality of the hay being better, we need to
stretch that hay as far as it will go. So a forage analysis on the hay is imperative. This
analysis will help us to balance our feed rations accordingly. Hay that has a TDN of 45%
must certainly be fed differently that hay that has a TDN of 67%. The only way to
accurately determine how a producer should feed that hay is by means of a forage
analysis. To get your hay tested you can contact your local county agent or contact the
Kentucky Department of Agriculture (www.kyagr.com) direct at 1-800-248-4628. This
year producers can’t just put out “X” number of bales to carry the cattle (or particular
livestock unit) until they get around to feeding them again. Knowing how many pounds
of hay that we are feeding a day to each unit will help stretch the hay and make the
animals do a better job of cleaning it up. Feeding racks will also help stretch the hay
further by keeping it up off of the ground so the animals won’t trample it.
The Department of Agriculture has implemented a “Hay Hotline” to help
producers’ source hay and other commodities from around Kentucky and other parts of
the country as well. That number is 1-888-567-9589. You may also go to the following
web address to obtain contact details for growers and brokers of hay and as well as listing
hay that you may want to sell.
http://www.kyagr.com/marketing/forage/HayForageDroughtRelief.htm
As you can see, there are some options and tools for livestock producers to utilize
during this short hay period. However, time is not on our side. Prices of hay and
commodity feeds will continue to rise as the year progresses. So, it is imperative that
producers sit down with their county agent, advisor or feed supplier to work out a feeding
plan that will carry them all the way through next spring or at least until new grass arrives
in mid to late March.
SUMMARY
The above are some of our thoughts at present. We will continue to monitor and
access the situation and provide additional information. We will add a “DROUGHT –
FORAGE” section to our Forage Website next week and add some other materials from
Kentucky and other states.
NITRATES IN DROUGHT STRESSED FORAGES – Ray Smith, Chad
Lee, Patty Scharko
(NOTE: The following is on the College Drought Page and will be listed on our
Forage website, but wanted to include it here for your info.)
Dry conditions often cause nitrates to accumulate at high levels in forages. Nitrate
levels need to be checked in drought damaged forages before feeding to livestock or
horses.
Sampling Technique
A proper sample must be taken for accurate determination of nitrate levels. The
following are some guidelines to follow:
Harvest at least one (1) pound of fresh weight for each sample. The plants should
be cut at the intended harvest height. We would suggest cutting the plants at no less than
three (3) inches above the soil surface. Nitrates tend to accumulate in the lower stems. By
keeping the cutting height above three inches, nitrate levels in the harvested plant should
be reduced. Collect a representative sample from each field. Usually five or more
locations across a field will serve as a representative sample. Plants from the five or more
locations in the field should be combined into one sample for nitrate testing. If multiple
fields are in question, wheat or other crops at different growth stages should be submitted
as separate samples. Growth stage, the date when fertilizer nitrogen was applied, and the
extent of freeze damage all could affect nitrate levels in the plants.
Cut plants should be stored in paper bags and mailed in cardboard boxes
overnight to the testing laboratory. The better option is to put the plant samples in a
cooler with ice and drive them directly to the laboratories the same day the plants were
harvested. If the plant samples will be stored overnight, then they should be stored in a
freezer in paper bags. When collecting the plant samples, DO NOT put them in plastic
bags. Plant samples stored in plastic bags at room temperature will lower nitrate levels,
resulting in inaccurate results. During the handling process, nitrate levels could decrease
in the plant sample, especially if they are stored overnight at room temperature. If a
period of time has occurred between harvesting and testing the samples, then you could
expect that nitrate levels reported would be less than nitrate levels in the field.
Testing Laboratories
Murray State University Breathitt Veterinary Laboratories in Hopkinsville, KY will
return an answer within 24 hours. The Kentucky Livestock Disease Diagnostic Center
(LDDC) will return an answer within 3 or more days. Both labs charge $10 per sample.
Kentucky LDDC does not require a veterinarian to submit these samples. County ANR
Agents and private farmers from Kentucky CAN submit samples directly to LDDC.
Breathitt does require a veterinarian to submit the sample. If county ANR agents include
an email with the samples that the veterinarian submits, then the lab will send the results
to the agent as well as the veterinarian. Several commercial laboratories may conduct the
nitrate testing as well.
Contact Information
Murray State University Breathitt
Veterinary Center PO Box 2000
715 North Drive Hopkinsville, KY 42241-2000
Phone (270) 886-3959
Livestock Disease Diagnostic Center
1490 Bull Lea Road
Lexington, KY 40512
Phone (859) 253-0571
Fax (859) 255-1624
Different Feeding Recommendations
The University of Kentucky LDDC has the cut-off at 0.44% nitrate (Table 1),
while the Breathitt Laboratory has the “safe to feed” cut-off level at 0.20% nitrate (Table
2). The Breathitt Laboratory does not recommend mixing feed for any forage with nitrate
levels above 0.20%, while the LDDC offers recommendations for blending forages with
higher nitrate levels.
The UK LDDC recommendations were based on a committee of scientists
evaluating the best data available for nitrate levels in corn. The values in Table 1 assume
that vitamin A levels are adequate in the overall feed ration and no other non-protein
nitrogen (NPN) is in the feed ration. If the overall ration has vitamin A deficiency and/or
NPN, then the safe to feed cut-off should be lowered to 0.30% nitrate.
The Breathitt recommendations are based from a case of nitrate toxicity occurring
from a forage sample that tested about 0.23% nitrate several years ago. We do not know
if the forage sample was handled properly before it was submitted to the laboratory.
However, by having the cut-off at 0.20% nitrate, the personnel at the Breathitt lab know
that they will prevent any cases of nitrate toxicity.
Table 1. Nitrate Levels and Feeding Options (University of Kentucky
Recommendations)
Nitrate (NO3) in dry matter
Feeding Instructions
0.0 – 0.44% 0 – 4,400 ppm
Safe to Feed*
0.44 –
4,400 – 8,800 ppm Limit to 50% of total dry ration for pregnant
0.88%
animals.
0.88 –
8,800 – 15,000
Limit to 25% of total dry ration. Avoid feeding
1.50%
ppm
pregnant animals.
Over 1.50% Over 15,000 ppm
Toxic. Do not feed.
*assumes sufficient vitamin A and no non-protein nitrogen supplement in the overall feed
ration.
Table 2. Nitrate Levels and Feeding Options (Breathitt Laboratory
Recommendations)
Nitrate (NO3) in dry matter
Feeding Instructions
0.0 – 0.20% 0 – 2,000 ppm
Safe to Feed
Over 0.20% Over 2,000 ppm
Toxic. Do not feed.
Both laboratories are conducting similar methods for nitrate testing, such that a sample
reading of 0.20% should be the same for both laboratories. Both laboratories should
provide accurate readings of nitrate, assuming that the forage samples were handled
properly before arriving to each laboratory. At this point in time, the discrepancy between
the two laboratories will remain in the recommendation and not the results.
POINTS:
 Place the samples in a brown paper bag and not in plastic to send to the diagnostic
laboratory. Get the sample to the laboratory immediately. This avoids the
possibility to reduce the nitrate level during transportation.
 Use 0.30% (3,000 ppm) nitrate for safe feeding if uncertain about the vitamin A
and/or supplement.