Report of Progress 961-S

SUMMARY Six hard red (237, Jagalene, Jagger, OK0, Stanton, and Thunderbolt) and six hard white (Burchett, Lakin, NuFrontier, NuHills, NuHorizon, and Trego) winter wheat varieties were evaluated for grain yield and quality in the second year of the study. A split-plot design was used with four grazed and four ungrazed plots of each variety in two southwestern Kansas counties. Cattle were allowed to graze the wheat after it was well established. Cattle were removed before wheat began jointing in Stanton County, but were not removed until after jointing in Clark County. Grain was harvested from the grazed and ungrazed plots. Grazing did not influence grain yields in Stanton County. In Clark County, grazing reduced average yield by 9 bu/ acre. Grazing decreased test weights in Clark County, but increased test weights in Stanton County. Grazing increased crude protein content of 0 varieties in Clark County. In Stanton County, the protein response was less consistent. Grazing seemed to more significantly affect kernel weight, diameter, and hardness in Clark County than in Stanton County. Although variety differences occurred, grain yield and quality do not seem to be related to wheat color.


INTRODUCTION
The use of winter wheat as a source of forage for livestock allows producers to more effectively and profitably utilize their land.Wheat provides economical, high-quality forage at a time of the year when few other comparable forages are available.Wheat can be used as a forage source, or in a dual forage and grain program.Research has shown that grazing winter wheat can occur up to wheat jointing without reducing grain yield.An estimated 6 million acres of Kansas winter wheat may be grazed during a good forage-producing year.Little is known about the effect of grazing on grain yield and quality of the hard white winter wheat varieties.This experiment examined the effect of grazing on grain yield and quality of six hard red and six hard white winter wheat varieties.Results from the first year's experiment indicated that varieties may respond differently to grazing, and that heavy grazing may reduce crude protein.Grain yields were generally not reduced by light or heavy grazing, as long as the cattle were removed before jointing occurred.

PROCEDURES
Six hard white winter wheat varieties (Burchett, Lakin, NuFrontier, NuHills, NuHorizon, and Trego) and six hard red winter wheat varieties (237, Jagalene, Jagger, OK0, Stanton, and Thunderbolt) were planted in two locations in southwestern Kansas.Producers had prepared the soil and applied 65 lb of nitrogen (Clark County) or 80 lb of nitrogen (Stanton County) per acre before wheat planting.On September 5, 2004, each variety was planted in four replicated plots at each location, in 0-inch rows at a depth of approximately .75 inches.The planting rates were 90 lb seed/acre at the Clark County plots and 20 lb seed/acre at the Stanton County plots.Eleven pounds of nitrogen (N) and 52 lb of P 2 O 5 /acre were applied with the seed.Soil type at both locations was a silt loam.Heavy rainfall and subsequent crusting of the soil surface after planting prevented the emergence of all varieties.All plots were sprayed with glyphosate to kill emerged wheat, and plotswere then replanted on October 6, 2005.The same planting rates were used, but N and P 2 O 5 were not reapplied.In late March 2005, liquid urea ammonium nitrate was applied at 30 lb N/acre at both locations.Stanton County plots received an estimated 4 inches of irrigation water in late April and May.Clark County plots were located in a dryland field.Total precipitation from January through May was similar in the two counties (Clark,7.88 inches;Stanton,7.95 inches).In June, Clark received 4.80 inches of rain, whereas Stanton County received 0.93 inches.
A split-plot design used grazing/ungrazed as the main plots and varieties as the subplots.All treatments were replicated four times at each location.The experiments were located within the producers' wheat fields, where stocker cattle were allowed to graze after wheat was well rooted and had sufficient tillering.Cattle were removed from the plots in Stanton County before wheat jointing began, but not until after jointing in Clark County.Grain was harvested in Clark County on June 22 and in Stanton County on June 27, 2005.Grain yield, moisture, and test weight were determined on the day of harvest.Grain samples were sent to the K-State grain laboratory for measurement of kernel diameter, hardness, moisture, and 000-kernel weight.These traits are part of the single-kernel characterization system (SKCS) used to determine grain quality.Samples were also analyzed at the K-State soil laboratory for crude protein (CP) content.

RESULTS AND DISCUSSION
Grazing did not affect grain variety yields in Stanton County, but reduced grain yields in Clark County by an average of 9 bu/acre (Table ).Stanton County yields ranged from 47 to 59 bu/acre and were significantly higher than yields for Clark County, which ranged from 2 to 47 bu/acre.The yield difference may be attributed to cattle removal before jointing in Stanton County and after jointing in Clark County.Heavier stocking rates were used in the Clark County experiment.Published research indicates that yields can be expected to decline to 2 bu/acre per day when wheat is grazed during the first week after onset of the first hollow stem.The varieties responded differently in the two counties.For example, Jagger was one of the top producers in Stanton County, but the poorest in Clark County, regardless of grazing condition.The variety by grazing interaction was primarily due to the grazing effects observed in Clark County and to the presence of Hessian fly.
Grain moisture at harvest (Table 2) differed between the two locations for grazed and ungrazed wheat.In Clark County, grain had higher moisture content when grazed than when ungrazed, which is commonly observed when wheat is grazed after first hollow stem.Grazing did not affect grain moisture in the Stanton County experiment.Test weights (Table 3) were higher in Clark County, but lower in Stanton County, for the grazed wheat.In both counties, Burchett, Jagalene, NuHills, and Thunderbolt had higher test weights, whereas 237 and OK0 had lower weights.Test weights of the other six varieties were not consistent between the two locations.Crude protein content (Table 4) differed between the varieties in each county, depending on the grazing conditions.Overgrazing in Clark County increased the CP in 0 of the varieties and reduced CP in 2 varieties.Protein was not affected in 8 varieties, was reduced in 2, and was increased in 2 with the early removal of cattle in Stanton County.Crude protein was higher in Stanton County than in Clark County.
Single-kernel characteristics of each variety were affected by gazing differently in each county.Grazing reduced the SKCS 000-kernel weight (KWT) of Jagalene, NuHills, NuHorizon, and Thunderbolt in both counties (Table 5).Jagger and Stanton 000 KWT were unaffected by grazing in either county.All other varieties responded differently to grazing in each county, such as having a higher kernel weight when grazed in Clark but a lower weight when grazed in Stanton County.Grazing generally seemed to reduce kernel weight more in Clark County than in Stanton County.Stanton wheat kernel diameter (Table 6) was not affected by grazing in either county.At both locations, NuFrontier and NuHorizon had smaller kernel diameters when grazed.Changes in diameter of the other 9 varieties were not consistent between counties or grazing system.There was a general tendency for the wheat grazed in Clark County to have smaller kernel diameter.All but two samples were within the medium kernel size classification (≥2.24 to ≤2.92 mm).Stanton wheat single kernel hardness (Table 7) was greater when grazed at both locations.Grazing decreased hardness of 237, Jagger, and Lakin, and increased hardness of the other 9 varieties in Clark County.In Stanton County, grazing increased the hardness of the Stanton wheat variety, but did not affect hardness of the other varieties.None of the Clark County wheats were indexed as 'very hard' (80 to 89), and none of the Stanton County wheats were 'medium soft' (60 to 64) or 'medium hard' (65 to 79).
Grazing had a greater impact on grain yield and quality in Clark County than in Stanton County.Visual observation suggested that the wheat in Clark County was grazed more heavily than wheat in Stanton County.Grazing continued after jointing in Clark, but did not in Stanton County.Although the total January through July precipitation was higher in Clark County, the experiment in Stanton County received an estimated 4 inches of irrigation water.The red and white varieties used in this study are not representative of all wheat varieties, but were selected because of their popularity or potential in southwestern Kansas.There did not seem to be any grain traits evaluated in these experiments that were strongly related to wheat color.

FoRAGe YIeLD AnD QUALItY oF HARD ReD AnD WHIte WInteR
WHeAt VARIetIes -YeAR tWo CoMPARIson

SUMMARY
This report discusses the second year's results comparing forage yield and quality of six hard white winter wheat varieties (Burchett, Lakin, NuFrontier, NuHills, NuHorizon, and Trego) and six hard red winter wheat varieties (237, Jagalene, Jagger, OK0, Stanton, and Thunderbolt).Experiments were planted in two southwestern Kansas counties, Clark and Stanton, in September 2004.The plots were replanted in October due to poor emergence caused by heavy rainfall after planting.Forage samples were collect from each plot during March and May 2005.Dry matter (DM) content, DM yield, crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), net energy for maintenance (NEm), net energy for gain (NEg), total digestible nutrients (TDN), relative feed value (RFV), and nitrate nitrogen were determined.Forage yield at the May harvests was higher than in March in both counties.Stanton County also had the lowest March and highest May yields.Forage quality was better at the March harvest than in May in both counties.May forage quality was higher at Stanton than in Clark County.High forage nitrate concentrations were found in both experiments with the May harvest.Although yield and quality differences existed between varieties, they did not seem to be related to wheat kernel color.

INTRODUCTION
Wheat pasture provides economical, high-quality forage for livestock during a time of year that few other quality forages are available.Research has shown that grazing winter wheat can occur up to the formation of the first hollow stem (onset of jointing) without reducing grain yield.Although hard red winter wheat varieties dominate in Kansas, some grazing of white wheats has occurred.Limited research has been conducted to examine forage yield and quality of white wheat varieties.This experiment is the second year's evaluation of the forage yield and quality of six hard white winter varieties and six hard red winter varieties popular in Kansas.Results from the first year's experiment showed location and variety differences in forage yield and quality.The variety differences did not seem to be associated with wheat color.

PROCEDURES
Six hard white winter wheat varieties (Burchett, Lakin, NuFrontier, NuHills, NuHorizon, and Trego) and six hard red winter wheat varieties (237, Jagalene, Jagger, OK0, Stanton, and Thunderbolt) were planted in two locations in southwestern Kansas.Producers had prepared the soil and applied 65 lb of nitrogen (Clark County) or 80 lb of nitrogen (Stanton County) per acre before wheat planting.On September 5, 2004, each variety was planted in four replicated plots at each location, in 0-inch rows at a depth of approximately .75 inches.The planting rates were 90 lb seed/acre at the Clark County plots and 20 lb/acre at the Stanton County plots.Eleven lb of nitrogen (N) and 52 lb of P 2 O 5 /acre were applied with the seed.Soil type at both locations was a silt loam.Heavy rainfall and subsequent crusting of the soil surface after planting prevented uniform emergence in both counties.The experiment was sprayed with glyphosate to kill wheat, and was replanted on October 6, 2005.The same planting rate was used, but N and P 2 O 5 were not reapplied.Stanton County plots received an estimated 4 inches of irrigation water in late April and May.Clark County plots were located in a dryland field.Total precipitation from January through May was similar in the two counties (Clark, 7.88 inches; Stanton, 7.95 inches).0 Forage samples were harvested on March 8, 2005, in both counties, and on May 2, 2005, at Clark County and May 3, 2005, at Stanton County.Fall forage growth was not sufficient to warrant an early-winter harvest, as in the first year's experiment.Cuttings were collected from the same 6 ft of closely clipped row length in each plot.Samples were dried, weighed for dry matter yield, and then sent to a commercial laboratory for CP, ADF, and NDF determination.Relative feed value, TDN, NEm, and NEg were calculated from the laboratory analysis, according to formulas shown in Table .Nitrate-nitrogen assays were performed at the USDA-ARS laboratory in El Reno, Oklahoma.

RESULTS AND DISCUSSION
Total forage production was greater in Stanton thanin Clark County (Table 2).Averaged over all locations and harvests, 237, Stanton, Thunderbolt, and Trego were among the leading total forage producers, whereas Lakin was the only variety with a total yield less than 3000 lb/acre.May yields were higher than March yields in both experiments (Table 3).Averaged over locations, NuFrontier produced less forage in the first harvest than Jagger or Stanton did; all other varieties were similar.NuFrontier, Stanton, Thunderbolt, Trego, and 237 produced the most May forage, exceeding 2400 lb/acre averaged over locations, whereas Lakin or NuHills were the lowest producers in May, with 2000 lb/acre or less.It is interesting to note that a variety like NuFrontier was the lowest March forage producer and one of the highest May forage producers.Variety differences at individual harvests and for total annual production do not seem to be related to kernel color because there were high-and low-yielding red and white wheat varieties.
Crude protein content ranged from 0.0 to 24.4% (Table 4).Averaged over all harvests and counties, Burchett, Jagalene, Lakin, NuHills, and Thunderbolt had higher crude protein than did OK0 and NuFrontier.March growth had the highest CP content in both locations.Forage in Clark County had both the highest March and lowest May CP.Crude protein did not seem to be related to wheat color.
Acid detergent fiber, a measure of cellulose and lignin plant fractions, increases as a plant matures.Greater ADF is associated with less forage digestibility and energy availability.Neutral detergent fiber (NDF) measures hemicellulose, cellulose, and lignin.As NDF increases, feed intake tends to decrease.Both March harvests had lower ADF (Table 5) and NDF (Table 6) values, indicative of higher quality, than did the forages harvested in late spring.Although ADF and NDF were similar for both counties in March, May ADF and NDF values were lowest in Stanton County.
Because NEm, NEg, and TDN are calculated from ADF, and RFV is calculated from ADF and NDF, these four energy-related values showed similar responses in this experiment.March-harvested forages from each county had small to no differences in NEm, NEg, TDN, and RFV values (Tables 7 through 0, respectively).March values were higher than values from the May harvests.The values were lower in Clark than in Stanton County in the May forage.
The lower CP and energy-related values from forages harvested in May were attributed to a later stage of plant maturity.The varieties were in various stages of late boot to early heading at this harvest.Clark County wheat was at a slightly more advanced growth stage than Stanton County wheat was.March forage quality was similar in the two counties, and was higher than the May forage quality.Dry matter yield increases as a plant matures.In this experiment, DM yield was negatively related (P<.000) to CP (r = -.60),NEm (r = -62), NEg (r = -.63), and TDN (r = -.62),indicating that as yields increase, quality decreased.It should be remembered that forage quality of the May samples would be most applicable to wheat cut for hay at that time.If the forage had been properly grazed to sustain vegetative growth, the protein and energy values would have been closer to the March nutrient analysis.
High nitrate concentrations (>3000 ppm) were found in some of the forages (Table ).The least nitrate content occurred at the March harvest in each county, but with Stanton County forage having less.The high May concentrations were similar for both experiments.Of the 92 forage samples tested, 82.8% (n=59) had less than 3000 ppm (3 avg.), 6.7% (n=32) were between 3000 and 6000 ppm (3744 avg.), and 0.5% (n=) had 6927 ppm.
The various wheat varieties exhibited different growing patterns, depending on the time of year.Total annual yield differed between counties and varieties.Forage quality was affect by the time of harvest and the associated stage of plant maturity.The varieties chosen in this experiment are among the more popular wheats planted in Kansas, but they do not represent all varieties, colors, growing conditions, or cultural practices.Forage traits seem to be related more to individual variety characteristics than to wheat kernel color.

PROCEDURES
Nine varieties and one commercial mix of cool-season grasses were planted in two counties in southwestern Kansas in the fall of 2002.The varieties were 'Achenbach' smooth bromegrass, 'Slate' intermediate wheatgrass, 'Hycrest' crested wheatgrass, 'Kentucky 31' and 'Max-Q' tall fescue, 'Profile' orchardgrass, 'Hykor' festulolium, and 'Dixon' and 'Lakota' matua grass.Kentucky 31 was endophyte free, whereas Max-Q carries an endophyte that does not produce toxins harmful to livestock.Festulolium is a cross of tall fescue and perennial ryegrass.The matuas have been called bromegrass, but are actually a rescuegrass.Reportedly, Dixon is better adapted to southern climates, whereas Lakota has a northern adaptability.The mix was Sharp Brothers' 'Pasture Mix #6', a blend of smooth bromegrass, 'Regar' meadow bromegrass, Slate, Profile, and 'Garrison' creeping foxtail.Each variety and the mix were planted in four randomly assigned plots in both locations.The Ford County plots were under a 2.4-acre center-pivot sprinkler on a Ulysses silt loam soil.The Stevens County plots were under a 5-acre pivot on a Vona-Tivoli loamy fine sand.
Urea (50 lb N/acre) was applied to both experiments in the early spring before new growth began.During the summer an additional 00 lbs N/acre was applied as urea.The grasses were harvested when all varieties had reached an early-boot to early-head stage of maturity.Harvests occurred on May 26th in Ford County and on June 7th in Stevens Counties.Spring yields in both counties were indicative of dryland conditions because neither experiment had been irrigated before the harvest.Irrigation began in Ford County the week after spring harvest, with approximately 2 inches of water was applied through October.Irrigation did not occur in Stevens County until July 23rd, when the experiment received approximately 4 inches in the one and only watering.
Fall harvests occurred on October 2st and 3st in Ford and Stevens counties, respectively.Forage samples were clipped to a 4-inch height and collected from a 20-square-foot area of each plot.The samples were oven dried to determine moisture content and DM yields.

RESULTS AND DISCUSSION
Total annual forage yields (Table ) in Ford County were greater for Hykor festulolium, Kentucky 3, Max-Q, orchardgrass, PM6 and smooth brome, poorer for crested wheatgrass, Dakota and Lakota, and equal for intermediate wheatgrass, compared with annual variety yields in Stevens County.The matuas had the poorest annual production in both counties.The yields of all other varieties in Stevens were similar.The annual variety yields in Stevens County, except crested wheatgrass, were considerably lower than in 2004.In Ford County, Kentucky 3 was the high yielding variety, although it did not differ statistically from PM6.Total forage production of each variety in Ford did not seem to be as high as in 2003, but tended to be as good as, or better than, 2004 for some varieties.
In Ford County, seven varieties (Hykor festulolium, Kentucky 3, Max-Q, orchardgrass, and PM6) had a poorer spring than fall production (Table 2).The Dixon and Lakota matua plots experienced 00% winterkill.Their fall production was due to new plant development from previous years' seed production.The other three varieties had better (crested wheatgrass and intermediate wheatgrass) spring than fall yields or equal (smooth brome) spring and fall yields.Well problems prevented irrigation until the week after spring harvest.Approximately 2 inches of water was then applied until the fall harvest.Ford County also received 3. inches of precipitation from June through October (Table 3).The difference between spring and fall forage production was the result of the additional irrigation water.
Spring forage production of each variety (2963 to 6562 lbs DM/acre) in Stevens County was higher than fall production (37 to 792 lbs DM/acre).The county received 2.2 inches of precipitation from June through October.The plots received approximately 4 inches of water with a single irrigation on July 23rd.Irrigation was not possible until then because of well problems.
A comparison of the spring yields in both counties showed that Stevens yields were equal (Kentucky 3, PM6 and smooth brome) or greater (crested wheatgrass, Dixon, Hykor festulolium, intermediate wheatgrass, Lakota, Max-Q, and orchardgrass) than those in Ford County.The higher spring production in Stevens County seemed to be the result of more precipitation and a later harvest.Ford County fall yields, however, were equal to (crested wheatgrass, Dixon and Lakota) or greater than (Hykor festulolium, intermediate wheatgrass, Kentucky 3, Max-Q, orchardgrass, PM6, and smooth brome) Stevens fall yields.
County and harvest-date differences in the forage DM content of each variety were likely related to plant maturity at the time of cutting (Table 4).This year's data are the result of unplanned reduced irrigation, which significantly restricted forage production.Ford County yields were more similar to previous years' values than were yields at Stevens County, although Stevens had better spring yields.The data suggest that timing of irrigation water is at least as important as the amount, and that severe water restriction will significantly reduce production.

SUMMARY
Seventeen annual and perennial warm-season grasses of different species and varieties were planted in Grant and Stevens Counties in southwestern Kansas in 2002 to evaluate yield and adaptability under irrigation.The varieties included switchgrass, eastern gamagrass, crabgrass, buffalograss, seeded bermudagrass, and sprigged bermudagrass.This year's total annual bermudagrass yields in Grant County, without irrigation or fertilizer, ranged from 4083 to 5873 lbs of dry matter (DM) per acre, with no difference among varieties.Precipitation totaled 2.8 inches from January through August for the county.First-harvest variety yields in Grant County were higher than yields from the other two harvests which did not differ from each other.Annual Stevens County bermudagrass yields ranged from 3589 to 7065 lbs DM/acre, whereas the yields of the other five grass species were 7 to 5,527 lbs.Stevens County yields of all 0 bermudagrass varieties, buffalograss, and eastern gamagrass were greater at the first harvest than at the second, but did not differ at the third harvest for seven of these 2 varieties.Switchgrass was the only grass that had lower yields at each subsequent harvest.Eastern gamagrass had the highest yield of all the Stevens County grasses.'CD-90160' had the highest and 'Quickstand' had the lowest bermudagrass yields.Crabgrass varieties' spring emergence was poor, resulting in only one harvest and the lowest forage yields.But 'Red River' yields were two times greater than the 'Variety Not Stated' (VNS) crabgrass.This year's yields were considerably lower than last year's because of the rain-fed-only condition in Grant County and the small amount of additional irrigation water in Stevens County.
The Stevens County plots received a total of 300 lbs N/acre (as urea) in three split applications, before spring green-up and after the first and second harvests.Phosphorus and potassium were applied during the previous fall, with amounts based on soil test results and K-State recommendations.The plots received approximately 4 inches of irrigation water at one watering on July 23rd.The Grant County plots were not fertilized or irrigated during 2005.Well problems at both locations limited or eliminated irrigation.
Forage samples were collected from a 20-squarefoot area of each plot.Bermudagrass and buffalograss samples were harvested to a height of 3 inches, switchgrass to 8 inches, eastern gamagrass to 0 inches, and crabgrass at ground level.Harvests were made on June 23, July 28, and September in Grant County, and on June 24, July 29, and September 2 in Stevens County.All varieties were harvested three times, except crabgrass, which was harvested once on September 2 because of poor emergence and growth.Switchgrass and eastern gamagrass were harvested from the same section of row at each harvest.The samples were oven dried to determine DM content and yield.

RESULTS AND DISCUSSION
Total annual forage production ranged from 4083 to 5873 lbs DM/acre in Grant County, but did not differ among varieties (Table ).First-harvest yields (880 to 3272 lbs/acre) were all greater than the second (955 to 92 lbs/a) (Table 2).Yields of the third (765 to 620 lbs/acre) harvest were similar to the second.At the first harvest, LCB84x19-16 and World Feeder produced more DM than all other bermudagrass varieties.There were no differences in yield between varieties at the second harvest.The two experimental varieties, LCB84x6-66 and LCB84x9-6, had higher yields than Wrangler or World Feeder at the third harvest.Ozark, LCB84x9-6, and LCB84x6-66 were among the highest producers, with Wrangler and Hardie among the poorest producers at each of the three harvests.The Grant County plots should be considered as dryland because they were not irrigated during 2005.Total county rainfall from January through August was 2.8 inches (Table 3).
Eastern gamagrass and switchgrass had the highest total production in Stevens County.The highestproducing bermudagrass was CD-9060.Red River and VNS crabgrass had the lowest total yields, but these varieties were only harvested in September because of poor sprouting and growth.The nextpoorest-yielding grass was buffalograss, which did not differ from Quickstand bermudagrass.There were few significant differences among the remaining bermudagrasses.Of the seeded bermudagrass varieties, CD-9060 and Vaquero were in the highest-producing bermudagrasses, wherea the Wrangler yield was among the lowest.head weighing an estimated 900 to 200 lb.Five samples, collected from each field on each sampling day, were separated into the four plant parts, oven dried, and weighed.Samples were analyzed for crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF).Total residue averaged 11,196 lb of dry matter (DM) at the onset of grazing, and decreased over the entire grazing period.Leafs and husks accounted for the majority of this decrease, inasmuch as DM of stems essentially remained unchanged.Dry matter of cobs, although decreasing over time, was a smaller percentage of the total residue weight.Initial grain weight was low, at 36 to 475 lb/acre.Grain was not found in samples after an average 33 days of grazing, even though small amounts of whole and broken kernels could be seen in the manure for several more weeks.The small amount of grain did not significantly increase total residue energy.

INTRODUCTION
Corn harvest residue can be an inexpensive source of feed for cattle.It can supply a dry cow with a large portion of her nutrient requirements during early pregnancy.Part of the nutrient value of the residue comes from corn grain that was not harvested.Grain combine improvements have increased harvest efficiencies, and Bt (Bacillus thuringiensis) corn hybrids have reduced lodging.Both technologies have increased corn grain yields by reducing loss; loss that had been available to livestock.This survey examines the corn plant fractions available to livestock after grain harvest.

PROCEDURES
Samples of harvest residue were collected from six 60-or 120-acre irrigated corn fields in Grant County.The first sample from each field was taken the same day cattle were moved onto the field, and the last sample was collected within a day after cattle removal.The length of grazing was different for each field (30 to 86 days, 52 days average), with the sampling period beginning on October 29, 2003, and ending on January 23, 2004.Herd size ranged from 27 to head of cows or first calf heifers weighing an estimated 900 to 200 lbs (034 lb average).Cattle were supplemented with mineral and protein blocks.
Five locations along the radius of each full-or half-circle field were sampled on each collection day.Samples were collected for 3, 4, or 5 days, depending on the length of grazing.There was an average of 5 days between collections while grain was present in the sample, and 29 days when grain was not found in any samples.
Plant residues were collected from a 42-inch diameter area and separated into stalks, leaves and husks, and cobs.Corn grain was collected from between two corn rows for 200 feet and separated from the cob.All samples were oven dried and weighed to determine dry matter weights.The samples were then combined by day and plant parts, and then sub-sampled for laboratory analysis of CP, ADF, and NDF.
Weights of the five field samples were averaged to 22 observations used in regression analysis of stalk, leaf and husk, cob, and grain as a percentage of the total weight.Total residue weight was also regressed.Day was included in all models, which also examined the number of animals per acre and the estimated average body weight of cattle on each pasture, as well as all possible cross-product and quadratic variables.Model selection was based on results of the SAS RSREG procedure, optimal r-squares for the fewest statistically significant variables, and minimal collinearity.
This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

RESULTS AND DISCUSSION
Residue weights and weight changes during grazing are most accurately described as dry matter disappearance, of which animal intake is assumed to represent the major portion.Other causes of disappearance could include wind and trampling.Total residue weight averaged ,96 lb/acre at the beginning of grazing and 9,067 lb/acre at the end (Table ), with an average disappearance of 40.9 lb/acre per day.Leaf and husk weights decreased from a starting weight of 5,756 lb/acre to 3700 lb/acre at the end, with an average daily disappearance of 39.5 lb/acre.Cob weights decreased during grazing by an average of 5.7 lb/acre per day.Starting and ending weights were 840 and 544 lb/acre, respectively.Although it seems that stem weight increased during grazing, this is not realistic, and was probably the result of inherent sampling errors.Grain weights at the beginning of grazing ranged from 36 to 475 lb/acre.The high value came from a field that had a considerable amount of lodging.Lodging was not seen in the other five fields.Grain was not found in the samples after an average 33 days grazing, but a small amount of whole and broken kernels could be seen in some manure pats for several more weeks.Average daily disappearance for the 33 days was 4.4 lb/acre.
Regression equations for total weight of residue DM and percentage of each plant part are shown in Figure .The disappearance of total pounds of residue was largely affected by the number of grazing days and cattle per acre.The decrease in percentage of leaf and husk were more affected by head and weight than by day.The regression equation of the percentage of stalk predicts an increase over time.This would occur when stalk weight remained constant or when it decreased at a slower rate than total residue weight.From visual observations, the cattle did not seem to consume any significant amount of stalk.The beginning and ending stalk weights suggest that an increase occurred.It is likely that stalk weight remained somewhat constant, with total weight declining, thus causing the percentage increase.The grain regression predicts availability until day 49.It is interesting that although grain was not found in the samples after day 33, it could be seen in manure.The r-squares of these equations indicate that the selected model variables do at least a fair job of explaining the total weight and percentage changes.The r-square for cob was low, and no level of statistical significance was found for any of the models or variables tested.
Crude protein of leaf and stem was similar, at 3.7 and 3.6%, respectively (Table ).Cob CP was less than half that of leaf or stem (.6%).Protein was highest in the grain (8.9%).Cob tended to have higher NDF, TDN, NEm, and NEg values than leaf did, whereas stalk had lower values than leaf did.Stalk had higher and cob had lower ADF than did leaf.Table 2 shows TDN and net energy values calculated from residue weights, laboratory results for ADF, and NRC (996) energy values for grain.The amount of grain available at the start of grazing (36 vs. 475 lbs) had little effect on total energy because it was a relatively small percentage of the total residue.
Assuming that the largest part of the DM disappearance is due to cattle intake, this survey suggests that cattle will quickly consume any available grain.It was apparent that the cattle were able to find small amounts of grain that were not found in the sampling procedure used in this survey.It also seemed that the cattle preferred leaves and husks over stalks, and may avoid stalks if enough leaves are available.

Table .
The effect of grazing on wheat variety grain yield (bu/acre at 3% moisture), 2005.

Table 2 .
The effect of grazing on wheat variety grain moisture (%), 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table 3 .
The effect of grazing on wheat variety grain test weight (lb/bu), 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.
* SCKS kernel diameter: <2.24 mm, small; ≥2.24 mm -≤2.92 mm, medium; >2.92 mm, large.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table 7 .
The effect of grazing on wheat variety grain SKCS kernel hardness index*, 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table .
Formulas used to calculated TDN, NEm, NEg, and RFV from ADF and NDF.

Table 2 .
Total annual forage dry matter yield (lb DM\acre) by county and variety, 2005.

Table 3 .
Forage dry matter yield (lb DM\acre) by county, harvest, and variety, 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table 7 .
Total digestible nutrients (% of DM) by county, harvest, and variety, 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table 8 .
Net energy for maintenance (Mcals/00 lb DM) by county, harvest, and variety, 2005.This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Curtis Thompson, Troy Dumler, Tom Roberts, Tim Jones, and Monte Hampton Dodge
City Community College, Dodge City, Kansas.CooL-

seAson GRAss YIeLDs FoR 2005 WItH UnPLAnneD ReDUCeD IRRIGAtIon
Ford County.Spring yields in Stevens County ranged from 672 to 5088 lbs DM per acre.Calves from the surrounding pasture in Stevens County gained access to the plots just before the fall harvest.Forage production in 2004 ranged from 566 to 9032 and from 689 to 4,552 lbs/a in Ford and Stevens, respectively.The results of these two years have been published in the 2005 K-State Cattlemen's Day report, 2005 Beef Cattle Research.This report discusses 2005 yields of the same grass varieties, as affected by much less irrigation water than previous years.

Table .
Total annual dry matter yield (lbs/acre).This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

seAson GRAss YIeLDs FoR 2005 UnDeR LIMIteD oR no IRRIGAtIon by Ron Hale, Curtis Thompson, Troy Dumler, Darl Henson, Tom Roberts, and Tim Jones
The increased third-harvest yields in Stevens were presumably the result of 3.3 inches of precipitation in August and approximately 4 inches of irrigation water on July 23.INTRODUCTION Irrigated plots established in southwestern Kansas have been used to compare the yields and adaptability of various warm-season grass species/varieties.In 2004, annual yields of bermudagrass ranged from 9529 to 2,030 lbs DM/acre in Grant County and from 6026 to 11,862 lbs in Stevens County.The other five grass species in Stevens County yielded from 654 to 2,259 lbs/acre.The plots in both counties received a minimum of 22 inches of irrigation water in 2004.The results have been published in the 2005 K-State Southwest Research-Extension Center report.This report discusses 2005 forage yields of the same plots as affected by very little or no irrigation water.
are two experimental varieties being evaluated by Kansas State University and Oklahoma State University.Vaquero is a blend of CD-9060, 'Mirage', and 'Pyramid' bermudagrass varieties.The Stevens County plots were under a 5-acre pivot on a This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived.Current information is available from http://www.ksre.ksu.edu.

Table .
Total annual dry matter yield (lbs/acre).

CoRn HARVest ResIDUe DIsAPPeARAnCe DURInG GRAZInG by Ron Hale and Darl Henson
SUMMARYCorn harvest residue was sampled on six irrigated corn fields in southwestern Kansas to measure the changes in stem, leaf and husk, cob, and grain during cattle grazing.The center-pivot irrigated fields were either 60 or 20 acres and were grazed for 30 to 86 days betweenOctomber 29, 2003, and January 23, 2004.The cow and first-calf heifer herds ranged from 27 to