8-115.‘ August I97.‘ Summary In 2 out of the 3 years from 1971 to 1974, desi of Coastal bermudagrass gave significant increas small grain-ryegrass forage yields early in the se One-fourth pound of paraquat per acre appeared adequate. The economic advantage from the earl duction has not been determined. Early forage yields from sodseeded small ryegrass correlated significantly and positively with; average minimum temperature in November. The l of the first frost desiccation also had a significant infl on early forage yields of sodseeded winter forage. A 4-week delay in seeding date (from Septem to October 23) resulted in an 8-week delay in th harvest. However, total production of small ryegrass forage was reduced by only 5 to 1O perce the later seeding. Prepared seedbed small grain-ryegrass pro substantially more forage than the same species , seeded into Coastal bermudagrass. Production d'g ences were generally greatest in the fall when product from sodseeded forage was only 2O to 3O percent of‘ y produced on seedbeds. These growth differences, ca by systems narrowed in the spring and total productio; winter forage, varied from46 to 66 percent and 63 t percent for the low and high rates of applied nitroé respectively. a Production ratios of sodseeded to prepared seed systems generally increased with early fall, winters, . spring rainfall quantities. Disking plus an application of one-fourth o paraquat per acre before seeding with small ryegrass significantly reduced fall growth of Coastal mudagrass. However, the treatment effect on spf growth of the warm-season perennial was negligible; ;> No-till and Seedbed Production of Small Grains-Ryegrass Mixture for Forage in East Texas J. E. Matocha* Small grains and ryegrass have been utilized for orage by beef and dairy industries throughout Texas. Ilimatic conditions in the eastern portion of Texas usu- llly are conducive to good production; however, year to Iear variation in forage yields can be rather extreme. Forage production from cool-season annuals is ex- )ensive. However, these crops produce high quality for- age during the season when green forage is limited. Small grains will normally give as much or more early and total ;easonal production of forage than other cool-season an- iuals. Oats, rye and wheat are the principal small grains lsed for grazing in East Texas. At least three systems of producing winter forage 13V€ been tried. These include (1) good prepared ;eedbed (one-way plow or several diskings), (2) semi- :illed (disked once) and (3) overseeded with no tillage. Recently, interest in use of chemicals exclusively (no-till) )1‘ with limited tillage to reduce competition from warm- ieason perennials on small grain seedlings has led to mother possible system of winter pasture production. Holt, Norris and Lancaster (1969) reported on sev- aral years of research in production and management of ;mall grains for forage in the State and in East Texas. The fesearch largely included only the prepared seedbed ;ystem of small grains production. Nitrogen fertilization lS a factor affecting early forage production from small grains-ryegrass in East Texas has been studied and re- ;ults reported by Holt et al. (1969), Matocha (1972) and Vlatocha, McCartor and Ott (1971). A majority of the ;tudies reported have been conducted on prepared ;eedbed systems of pastuireproduction. "Associate professor, The Texas Agricultural Experiment Station, Overton. Mention of a trademark or a proprietary product does not constitute a guarantee or a warranty of the product by The Texas Agricultural Experiment Station and does not imply its approval to the exclusion of other products that also may be suitable. Topography and excessive wetness in certain areas, limited farm equipment and high fuel costs encourage sodseeding establishment of winter pastures. Certain costs, such as seed and seeding, are inherent to both the prepared seedbed and sodseeding systems of winter forage production. Other costs, such as seedbed prepara- tion and fertilizer, will vary with seeding method. Recent increases in fertilizer, fuel and seed costs have made it imperative to use the system that can maximize profits. Coastal bermudagrass is the principal summer pe- rennial grass used in intensified forage production in East Texas. An established stand with a history of moderate rates of fertilization was used in the no-till and limited tillage evaluation of small grains. Because of its tremen- dous production potential, this grass exerts extreme competition on winter pasture seeded in early fall. The rationale used in selecting this particular warm-season perennial for sodseeding was based on the corollary that maximization of profit per acre would have to involve a strong summer forage program as well. The purpose of this publication is not to present cost economics of the winter pasture systems but rather to present results of the evaluation of the various systems and the effect of factors influencing the sodseeded system of winter forage production. A later paper will report on the effects of sources and rates of fertilizer on forage production from small grain. EXPERIMENTAL PROCEDURE The experimental site was located on an excellent stand of Coastal bermudagrass which had a history of low to moderate rates of fertilization. The soil type was a Reklaw sandy loam more recently reclassified as a Cuthbert series (Typic Hapludult). This soil has a vari- able, rather shallow, gravelly surface horizon (O-8 inches) overlying a dense clay layer. The selected site was at the north division farm of the Texas A&M University Agricul- tural Research and Extension Center at Overton. "1 The study involved three separate date-of-seeding experiments which evaluated rates and carriers of paraquat used in chemical desiccation of Coastal ber- mudagrass. Major studies were conducted in the 1971- 72, 1972-73 and 1973-74 growing seasons following a preliminary study initiated in the 1970-71 season. Early date-of-seeding studies were started on September 19 and 24 in 1972 and 1973, respectively. A mid seeding date in all years of the experiment ranged from October 4 to October 8. A late seeding date of October 23 was evaluated in 1972. Paraquat (1, 1'-dimethyl-4, 4'-bipyridinum dichloride) was used as the chemical desiccant with two types of carriers, fertilizer nitrogen solution (Uran) or water plus a surfactant, Ortho X-77 Spreader. All treat- ments were sprayed with 60-pound-per-square-inch pressure to obtain a fine mist. The aqueous solution of paraquat was applied at a rate of 30 gallons per acre while the fertilizer solution-paraquat mixture was applied at a constant rate of 120 pounds of nitrogen (N) per acre both with and without paraquat. This equaled 375 pounds per acre (35 gallons) of solution, since the Uran contains 32 percent nitrogen. Paraquat rates were 1/8, 1/4 and 1/2 pound active ingredient per acre mixed with water and 1/8 and 1/4 pound mixed with fertilizer solution. In all years the Coastal bermudagrass was clipped to approximately 2 inches of the surface and allowed a few days of regrowth before it was sprayed. In the 1971 and 1972 seasons, the small grain was drilled into the sod 2-3 days before chem- ical desiccation of the sod. This was intended to prolong the desiccative effect and to further reduce the competi- tion of the warm-season perennial. Spraying was per- formed immediately before seeding to start the 1973-74 season. A The treatments were applied to 8- by 12-foot plots with treatment allocations arranged in a randomized, complete block design with four replications. Adequate soil fertility was maintained by split applications of fer- tilizer totaling 24O pounds of nitrogen per acre, 120 pounds of phosphate (P205) per acre and 180 pounds of potassium oxide (K2O) per acre. All plots except the fertilizer check received the same rate of fertilizer. Am- monium nitrate (NH4NO3) was the source of nitrogen in all plots not treated with Uran. Triple superphosphate (O-46-O) and muriate of potash (O-O-60) were sources of phosphorus and potassium. The nitrogen was split into three applications, half at seeding, one-fourth in De- cember and one-fourth about February 1. Phosphorus was supplied in a single application at seeding, while potassium was split into two applications. Riley 67 wheat at 9O pounds per acre and tetraploid ryegrass at 1O pounds per acre were seeded in 1971, while Bonel rye at 75 pounds per acre and common ryegrass at 1O pounds per acre were used in the last two seasons. The center 3 feet of each plot was clipped at a height of 21/2 inches for yield determinations. Clippings were usually scheduled on a monthly basis starting in November and excluding December. A lower frequency of clippings was used in the last season (1973-74). 4 increase due to chemical desiccation. Similar data? In order to obtain data on actual production, grain-ryegrass forage produced in the early fall and spring was hand-separated from bermudagrass for“ This enabled evaluation of paraquat in altering vege competition of the two grass systems. RESULTS AND DISCUSSION Effect of Bermudagrass Desiccation and Temperature on Small Grain Sodseeding a mixture of small grains and ry has been reported to furnish good grazing in East (McCartor and Taylor, 1971). Chemical desiccatio means of reducing competition from Coastal grass was intensely investigated by this author iii?’ search plots over a period of years. Data are report individual years since total dry matter production considerably with year. Comparative data are presented in Table 1 for cated treatments at a constant rate of one-fourth po paraquat per acre and for nondesiccated treatment the 3 years (1971-74). Early seasonal as well as seasonal production was variable in all years. Data 1971-72 fall season show a significant increase matter yields of wheat-ryegrass as a result of desicca, of the Coastal bermudagrass at seeding. The en if ment of wheat growth occurred early in the fall) continued with ryegrass contributing to the mixed forage. Sigiificant differences were observed un sixth harvest on March 21. Cumulative yields for season showed almost a 500-pound-per-acre dry m 1972-73 showed no significant treatment effects. H ever, early season data (harvest 1) for 1973-74 at the and medium nitrogen application rates showed at le 50-percent increase in forage yields due to desiccati the bermudagrass. ' Growth obtained from the small grain-ryegr January 2O was not always a good indicator of total duction for the season. For example, dry matter coll.’ by January in 1971-72 was almost twice that for the responding period the following season; howe cumulative production for 1972-73 was twice th 1971-72. The third season, 1973-74, produced the est initial yields as well as the highest cumulative toi Production in the third season ranged up to 5O perif more than in the previous season. Forage production through January 15 was 656 and 862 pounds per acre which represented 32, 8 an percent of total seasonal production for 1971-72, 19 and 1973-74 seasons, respectively (Table 2). Early for? yields correlated positively with lateness of first frost?) _ average minimum temperature in November for f: A three seasons (Figures 1 and 2). However, relative duction (percent of total yield produced by Januaryfi, was not positively related to average November temp tures and frost dates because of substantial difference _ a spring rainfall (Appendix Table 1) during the time the bulk of the forage was produced. This suggests fall production and spring production are indepen and that both are related to temperature, assuming if moisture is adequate. 1200 ¢= 4350 + 43.29x l’ = 900 600 300 1 l ___” 1 1 1 3O 35 4O ,45 AVERAGE MINIMUM TEMPERATURE 5O ‘igure 1. Relationship between average 11111111111111] temperature in lovember and yields of small grain-ryegrass by ]anu'ary15 (1971-73). ields are merztged over desiccated and undesiccated plots (Seeded lctober 8i. Effect of Paraquat Rate and Seeding Date The eiTectiveness of the paraquat in immediate des- rcation and in longevity of the knockdown varied with 1e rate of application and the carrier as shown in Table 3. ’lant response data to rate of paraquat and seeding dates re shown in Tables 4 and 5. Early seeding dates in 1972 nd 1973 were September 18 and 24, respectively. The tte seeding date of October 23 was evaluated only in 972. noo- A A 4 Y=-620+29.62X £ f = a 900- . a (I973) i 3 soo- 1 8 _ o IL 5 g 3001'“ O g (1971) o | l l l l l; l so as 4o 4s ‘so ss DAYS UNTIL FIRST FROST Figure 2. Relationship between days until first freeze and yields of small grain-ryegrass by January 15. Yields are for plots receiving chemical desiccation at seeding (Seeded October 8). In the 1972-73 early seeding date, only a slight and nonsignificant increase in production of rye-ryegrass oc- curred when paraquat rates were increased (Table 4). However, as would be expected, increasing the paraquat rate from 1/8 to 1Z2 pound per acre decreased dry matter production of the Coastal bermudagrass and rye-ryegrass mixture at the first harvest. The activity oflparaquat was ABLE 1. EFFECT OF DESICCATING COASTAL BERMUDAGRASS ON PRODUCTION OF SODSEEDED SMALL GRAIN AND RYE- iRASS (SEEDED IN EARLY OCTOBER), AS INFLUENCED BY NITROGEN RATES, OVERTON a ._ 1971-72 Production to clipping date (lb. DMl/acrel Nov. 29 Dec. 20 Jan. 10 Feb. 14 Mar. 10 Mar. 21 Apr. 7 May 2 Total 4O lb. N/acre Sodseeded—no desiccation 148a2 129a 134a 79a 128a 294a 373a 298a 1583a Sodseeded—desiccated 217b 242b 197b 1 18b 202b 375a 393a 325a 2069b 1972-73 Nov. 2O Jan. 22 Feb. 26 Mar. 13 Apr. 4 May 10 Total 20 lb. N/acre Sodseeded—no desiccation 83a2 73a 271a 504a 541 a 1091a 2563a Sodseeded—desiccated 1 02a 90a 262a 579a 488a 925a 2446a 40 lb. N/acre Sodseeded—no desiccation 94a 178a 703a 921 a 710a 1288b 3894a Sodseeded—desiccated 123a 173a 761 a 961 a 650a 959a 3627a 60 lb. N/acre Sodseeded—no desiccation 81a 187a 841a 1024a 775b 1287a 4195a Sodseeded—desiccated 105a 240a 925b 1037a 650a 1345a 4302a 1973-74 g l; Nov. 28 Jan. 4 Feb. 27 Apr. 24 Total 20 lb. N/acre Sodseeded—no desiccation 183a: 1 1 1a 369a 3068a 3731 a Sodseeded—desiccated 285b 107a 360a 2635a 3387a 40 lb. N/acre Sodseeded—no desiccation c»; a 310bc 335a 1118a 4147b 5910b Sodseeded—desiccated ‘ 514d 348a 1089a 3457a 5408b 60 lb. N/acre l. Sodseeded—no desiccation 510d 481a 1603a 4604a 7198c 41 Ocd 462a 1 548a 451 0a 6930c Sodseeded—desiccated gétiivalues followed by the same letter are not significantly different at the .05 level of probability, as determined by Duncan's Multiple nge Test. TABLE 2. EFFECT OF CHEMICAL DESICCATION OF COASTAL BERMUDAGRASS AND NITROGEN RATE ON EARLY PRO- DUCTION OF SMALL GRAIN-RYEGRASS 1971-72 1972-73 1973-74 lb. lb. lb. DM */ Per- DM/ Per- DM/ Per- acre cent acre cent acre cent t0 of to of to of Treatment Jan. 15 total Jan. 15 total Jan. 15 total 1201b. N/acre - No desiccation 156 6 294 8 Desiccated 192 8 392 12 240 lb. N/acre N0 desiccation 41 1 26 272 7 645 1 1 Desiccated I 656 32 296 8 862 16 360 lb. N/acre N0 desiccation 268 6 991 14 Desiccated 345 8 872 13 *Dry matter. enhanced when nitrogen solution (Uran) was used as a carrier. The synergistic efTect on desiccation is reflected in the visual ratings (Table 3) and in the bermuda-rye data for 1/8- and ‘A-pound-per-acre rates at the November 8 harvest (Table 4). Furthermore, the combination of fer- tilizer and herbicide appeared to seriously aflect the stand of rye in the early seeding-date study. The consis- tently lower production throughout the season from Uran with 1/4 pound per acre of paraquat as compared to am- monium nitrate was primarily due to stand reduction. TABLE 4. EFFECT OF PARAOUAT RATE AND NITROGEN SOURCE ON RYE-RYEGRASS SODSEEDED IN COASTAL BERMUD: interaction with the" paraquat-fertilizer solution treaf TABLE 3. VISUAL RATINGS (PERCENT) OF EFFECTIVENESS OF CHEMICAL DESICCATION OF COASTAL BERMUDAGRASSQI Days following application g Pa raquat, if lb./acre Carrier 2 5 14 1/6 Uran 60* 70 40 1/8 H2O 20 10 10r§~i :1 1/4 u ran 1 00 90 60 1/4 H2O 60 60 30 1/4 H2O + disk 60 70 a 30 1/2 H2 o 100 90 60 l; *Rating based on a scale of 100 = complete desiccation, 10 =“slighti3f desiccation. Paraquat in aqueous solution but with dry ammoniunf nitrate had a lesser effect on the rye stand even at a highe application rate. This is reflected in the significantlfgi‘ greater yields of rye-ryegrass treated with 1/2 pound pa; acre of paraquat in ammonium nitrate as compared wit the combination of paraquat at ‘A; pound per acre an. Uran. Delaying the seeding date some 4 weeks, or October 23, resulted in an 8-weel< delay in the fir? harvest (Table 4). The effects 6f the desiccant rate wer minimized by the later seeding date. The adverse etfe from combining paraquat and Uran on a stand of observed in the early date-of-seeding were not evidential the late seeding. This indicated a possible temperatug " ma". GRASS IN POUNDS OF DRY MATTER PER ACRE, 1972-73, OVERTON Early seeding date (Sept. 19) Paraquat Nov. 8 Dec. 19 Jan. 29 Feb. 13 Mar. 5 Mar. 22 May 8 Total rate, 2 3 _ ‘kl/acre N some R-RG 3 + Fi-RG R-RG e + R-RG Fi-RG e + Fl s. 1/8 NH4NQ3 100a‘ 6066 1336 3366 2666 6446 1210a6 1830a 2158a 4661 ab 6396a 1/8 U ran 97a 507b 133ab 285b 185a 524a 1048a 1907a 2249a 4179a 4931a 1/4 N H4 NQ3 128a 562bC 155b 310b 256b 618b 1222ab 1959a 231 Oa 4648b 5433a 1/4 U ran 90a 408a 73a 217a 144a 385a ~1 1 18a 2174a 3054b 4201 a 1/ 2 NH4 NQ3 122a 500ab 152b 341 b 285b 685b 1305b 1840a 2170a 4730b 5438a Late seeding date (Oct. 23) p Jan. 4 Feb. 16 Mar. 13 May 7 Total R-RG 3 + R-RG R-RG B + R-Fg 1/8 N H4 NO3 145a 594a 1073ab 2372ab 3650ab 4184b 546266;?) 1/8 U ran 149a 61 1a 1 O16ab 2122ab 3264ab 3898a 504036 1/4 NH4 N03 144a 603a 1 1 136 26706 39646 44306 63146Z§ 1/ 4 Uran 137a 632a 1044ab 1872a 2880a 3685a 4693afifi§ 04 Uran 226b 631 a 967a 1973a 3035a 3797a 4s69ai§1 Test. 2 Rye-ryegrass. 3Bermudagrass + rye-ryegrass. 4Serious Hairy chess infestation. 6 >5 IVaIues followed by the sarne letter are not significantly different at the .05 level of probability, as determined by Duncan's Multiple Raj INFLUENCE OF PARAQUAT RATE AND NITROGEN SOURCE ON PRODUCTION (IN POUNDS OF DRY MATTER PER SODSEEDED RYE-RYEGRASS AND OAT-RYEGRASS, 1973-74, OVERTON Clipping date Nov. 19 Jan. 10 Mar. 15 May 17 Total R + RG B + B + B + N source o + R01 one’ 0-a03 C-RG C-RG C-RG Rye U ran 1 16a4 24370 282a 342a 2629ab 2921 a 3369a 5982a U ran 167a 2233bc 334a 778bc 2542a 2824a 3821 abc 6169a NH4N03 136a 1682ab 272a 863b 2812bcd 3124a g 4083ab 5941a NH4N03 . 144a 1 126a 296a 1 181d 2859cd 3177a 4480b0 5780a NH4N03 143a 1 172a 291 a 998cd 2765bcd 3073a 4197ab 5537a Oats U ran 225ab 2495c 465a 362a 2766bcd 3073a 3818ab0 6395a N H 4 N0 3 274b 3421 d 560a 342a 2726abc 3029a 3902ab 7352b Uran 5580 2138bc 1016b 696b0 2599ab 2888a 4869bcd 6738ab U ran 6660 2 185bc 1 302b 564ab 3096a 3440a 5628d 7491 b N H4 N03 5440 1733b 1028b 895b0 2810bcd 3122a 52770d 6778ab N H4 N 0 3 5760 1277a 1 104b 9460d 2969de 3299a 5595d 6626ab N H4 N03 5700 1259a 1 1 12b 9790d 2797b0d 3108a 5458d 6458ab ryegrass, oat + ryegrass. lfudagrass + cereal-ryegrass. Ra -ryegrass. n columns across both species. However, final production figures still reflected ,1? yields from the combination of paraquat and Uran. Tlthough early production of small grain forage was fiicantly delayed by the later seeding date, total dry ‘production from the rye-ryegrass was reduced by -10 percent. Total forage produced, including l bermudagrass, was essentially the same regard- _seedin g date. of Seedbed reparation Preparation of a seedbed before seeding small grain egrass usually required more than one trip with a tandem disk if the sod was primarily bermuda- A flat-breaking plow or a rototiller will usually e a good seedbed with one trip over the sod. jiprhent costs in seedbed preparation are high. How- Efidiata in Table 6 and Figures 3 and 4 show that Ttétion of small grain-ryegrass forage in the seedbed ais substantially better than from the same grasses fifinto chemically desiccated sod. “Production values were variable from year to year th systems. Production at the firstharvest ber) ranged from less than 100 pounds of dry Arpper acre (sodseeded, 240 pounds of nitrogen, '1‘>3) to more than 900 pounds in 1973-74 when the § seeded small grain-ryegrass, even with chemical nt of bermudagrass, comprised a meager 20-30 nit of the production from prepared seedbed at the rvest and increased to 60-100 percent by the April trogen fertilization increased forage yields sub- y in all years and appeared to narrow the yield 1d was prepared (Table 6). Relative production I values followed by the same letter are not significantly different at the .05 level of probability, as determined by Duncan's Multiple Range difference between the sodseeded and seedbed systems. For example, in the 1971-72 season, a poor year from the standpoint of total seasonal forage production, dry matter yields for the two systems at 120 and 360 pounds of nitrogen per acre were 1,005 and 2, 198 pounds per acre and 2, 154 and 3,429 pounds per acre, respectively. Rela- tive production from sodseeded forage was 46 and 63 percent of that from prepared seedbed for these two extreme nitrogen rates. In the season when production was highest (1973- 74), 3,731 and 5,598 pounds per acre of dry matter were reported for the sodseeded and seedbed systems, respec- tively, at 120 pounds per acre of nitrogen. Comparative values at the high rate of nitrogen were 7, 198 and 8,754 poundsper acre of dry matter. Relative percentages of the two systems were 66 and 82 percent for the low and high nitrogen rates, respectively. Therefore, ratio changes due to nitrogen rate were 17 percent in the year of low production and 16 percent when production was highest. The data thus indicate that relative production differences due to systems will be similarly affected by nitrogen rates regardless of season. Another factor that had significant influence on the relative productivity of the two systems was climatic conditions during the growing season. Althoughearly fall growth of small grains was directly related to average minimum temperatures in November (Figure l), total seasonal production appeared more related to rainfall than to winter temperatures. The performance of sod- seeded small grain compared with prepared seedbed small grain was related to rainfall in the early fall and throughout the winter and spring. Production ratios in- creased approximately 20 percent at both low and high 7 TABLE 6. PREPARED SlEEDBED AND SODSEEDED PRODUCTION IIN POUNDS OF DRY MATTER PER ACRE) OF RYE-RYEGRASS AS AFFECTED BY NITROGEN RATES, OVERTON 1971-72 Clipping date N rate System (lb./acre) Nov. 29 Dec. 20 Jan. 10 Feb. 14 Mar. 10 Mar. 21 Apr. 7 May 2 Sodseeded 0 - 1 7a 74a 62a 73a 23a 1 31 a 1 3a} 34a Sodseeded 120 162w 1371, 1231» 79a 55a 2661» 695' 114a Seedbed 1 20 3450 3530 2560 199b 3560 216ab 167b 306b Sodseeded 240 148b 129b 134b 79a 128b 294b 3730 298b Seed bed 240 31 6c 4060 2320 1 64b 507d 475cd 3820 5280 Sodseeded 360 178b 161 b 165b 105a 198b 3930 518d 4360 Seed bed 360 4350 3850 2660 1 73b 735e 556d 3930 4860 1972-73 Nov. 2O Jan. 22 Feb. 26 Mar. 13 Apr. 4 May 10 May 110 Sodseeded 0 52a 25a 1 1a 25a 1 12a 704a Sodseeded 120 83a* 73a 271 ab 504b 541 b 1091 c Seedbed 120 109ab 3710 383bc 397b 959d 715a 941 a Sodseeded 240 94ab 178b 703d 9210 7100 1288d Seed bed 240 149bc 623d 5790d 494b 1 025de 857b 984a Sodseeded 360 81 a 187b 841 d 1024c 7750 1287d Seed bed 360 1 680 824e 5940d 397b 1 088e 1 228d 1458b 1973-74 Nov. 28 Jan. 4 Feb. 27 Apr. 24 Sod seeded 0 50a 14a 47a 742a Sodseeded 120 183a* 1 1 1a 369b 3068b Seed bed 1 20 8060 694d 5870 351 1 b0 Sodseeded 240 31 0b 335b 1 1 1 8d 41470d Seed bed 240 9200 809de 161 8e 521 0e Sodseeded 360 510b 4810 1603a 4604de Seedbed 360 8370 871e 1741 e 5305a *All values followed by the same letter are not significantly different at the .05 level of probability, as determined by Duncan's Multiple R Test. rates of nitrogen and appeared to be associated with fall rainfall increases from 9 to 18 inches and winter-spring rainfall increases from 26 to 39 inches. Production ratios for total dry matter changed only slightly with lower fall and winter temperatures as long as rainfall did not change substantially. A The effect of seedbed preparation on the seasonal I growth pattern of small grain-ryegrass over a period of 3 years is depicted in Figure 3. Generally, growth of the sodseeded cool-season annuals averaged less than 10 pounds of dry matter per acre per day for the months of November, December and January, regardless of year. At the same time, growth rates on prepared seedbed exceeded 10 pounds and approached 20 pounds per acre per day in some years. Plant performance in early and late fall 1973 exceeded by almost two-fold that of the first 2 years. Seasonal growth patterns fluctuated slightly among years, but peak growth rates generally occurred in March and April. These growth rates in the better years were in 8 the range of 60-80 pounds of dry matter per acre per . on sodseeded forage. At the same time plant growth the seedbed system ranged from 80-100 pounds of matter per acre per day. Effect of Small Grain Specie and Date-of-Seed Date-of-seeding and small grain specie had a nificant effect on the growth pattern of the forage. Dat Figure 4 show that the growth rate of sodseeded oat November and December was greater than that of I but these became almost equal in January and Febru Spring growth was greater for oats than for rye when b were seeded in September; however, when seede late October, rye production in February and Ma exceeded oat production, with oat production a greater in April. It appears that late-seeded oats h more difficult time establishing a good root system t rye. When soil temperatures increased in late March April the oats made catch-up growth, and the growth exceeded that of rye. 120,- - I20 I Seedbed 100 " Sodseed '97‘ ' 72 ' loo I Seedbed I Sedseed I972- 73 8O - a Seedbed — 8Q E. Sod seed I973- 74 l- 3 g Seedbed AVG‘ \ Sodseed ___ ' 60 '- - 60 a F‘ f iii: {- _. ... 4o - §:?f_ E - 4o r- ~ I: 1 ." ' Z " I I lT E E Figure 3. Influence of g E : ~20 seedbed preparation and a I E season 0n monthly growth Q §fi E E rates of small grain-ryegrass \j','. * mixtures at 240 pounds of 7 .~ s ‘Y’? , O nitrogen per acre. DEC JAN FEB MAR APRII. MAY Treatment Effect on Coastal Bermudagrass Coastal bermudagrass is the predominate forage at the first harvest in a sodseeded system with small grain- ryegrass (Tables 7 and 8). Seeding date, rate and carrier of paraquat and tillage treatment have a substantial effect on competition from Coastal bermudagrass. Dry matter yields of Coastal bermudagrass growing in association with winter forage up to the first harvest ranged from a few hundred pounds in the first year (1972-73) to a ton in the second year. The September seeding dates for both years were only a few days apart, Difference in the growth can be largely attributed to warmer temperatures and higher rainfall (Appendix Table l) during the 50-60 days following seeding in the second year. Paraquat sig- nificantly reduced regrowth of Coastal bermudagrass in the first year, when rate was increased from 1/8 to 1/2 pound per acre with water as a carrier. One-fourth pound /////////////////////i] per acre of paraquat with Uran reduced regrowth of the warm-season perennial more than paraquat with water as the carrier. The greatest suppression of fall growth of Coastal bermudagrass occurred when ‘A; pound per acre of paraquat was followed with disking and oats rather than rye was used as the small grain. Oats are generally more aggressive than rye in the early season and therefore may compete better with Coastal bermudagrass. As could be expected, seeding date had a great influence on the quantity of Coastal bermudagrass grow- ing in association with small grain-ryegrass. When the seeding date was as late as October 23, fall production from the summer perennial was negligible (Table 7). In the following season delaying seeding from September 24 until October 8 resulted in reduction of bermudagrass in the small grain forage by approximately two thirds at the first harvest (Table 8). - IOQ - 80 - 6O § E - 4O E Figure 4. Influence of I " 2O seedbed preparation, small I grain specie and seeding E date on monthly growth rates of small grain-ryegrass Q mixtures at 240 pounds of 100T Seedbed rye Early seeding § Sodseeded rye 9_l8_72 80 " I Sodseeded outs E [H] Sedseeded rye late seeding E 5 Sodseeded oats 10-23-72 5' 603- d i; £ E 40- 1 ' f E I a 20"- t s QRLEL Qjma E NOV DEC JAN FEB 3 D a n I APR“, ’ nitrogen per acre. TABLE 7. FALL AND SPRING YIELDS OF COASTAL BER- MUDAGRASS SODSEEDED WITH SMALL GRAIN AND RYE- GRASS AS INFLUENCED BY PARAOUAT SOLUTIONS AND SEEDING DATES, 1972-73, OVERTON Bermudagrass production (lb. DMl/acrel Small Paraquat grain rate, I specie lb./acre Fall a Summer, Spring Total first cutting Small grain seeded 9-19-72 Rye 1/8 in Uran 410bcd2 - 342a 752ab 1941bc Rye 1/4 in Uran 318b 380a 698a 1700b Rye 1/8 in H2O 506d 328a 834b 2165c Rye 1/4 in H2O 434cd 351a 785ab 1982bc Rye 1/2 in H2O 378bc 330a 708ab 1846bc Oats 1/4 in Uran 175a 426a 601a 873a Small grain seeded 10-23-72 Rye 0 in Uran 0 1062a 1062a NR3 Rye 1/8 in Uran 0 1142ab 1142ab NH Rye 1/4 in Uran 0 1008a 1008a NH Rye I/8 in H2O O 1278ab 1278ab NH Rye 11/4 in H2O O 1384b 1384b NH Oats 1/4 in Uran 0 1371b 1371b ‘Dry matter. 2All values in columns followed by the same letter are not signifi- cantly different at the .05 level of probability, as determined by Duncan's Multiple Range Test. 3 N ot harvested. Delayed seeding of small grain-ryegrass enhanced spring production of Coastal bermudagrass forage, as reflected in the last harvest of the winter forage (Table 7). This effect may be largely attributable to residual soil nitrogen. As a result of delayed seeding and nitrogen fertilization, more residual nitrogen was available for spring production of Coastal bermudagrass. Regrowth of Coastal bermudagrass following the last harvest of the winter pasture (summer, first cutting) was affected to some extent by fall treatment of the summer perennial. Data in Table 7 show that early summer pro- duction was lowest when the bermudagrass was treated with 1A1 pound per acre of paraquat in Uran and then‘ seeded to oats. The highest production occurred when only 1/8 pound per acre of paraquat was used with rye. A control treatment was not included in this study. ACKNOWLEDGMENTS Financial and material support for this research study was supplied by the Ortho Division of Chevron Chemical Company and Allied Chemical. 10 ‘ TABLE 8. FALL AND SPRING YIELDS OF COASTAL BER MUDAGRASS SODSEEDED WITH SMALL GRAIN AND RYE GRASS AS INFLUENCED BY PARAOUAT SOLUTIONS, TI AGE AND SEEDING DATES, 1973-74, OVERTON Bermudagrass production (lb. DMl/acr Small Summ" grain Paraquat ' specie rate, lb./acre Fall ,"-Spring Total Small grain seeded 9-24-73 Oats 0 in Uran 2270d2 307a 2577d NH3V"; Oats 1/8 in Uran 1580c 289a 1869c Nlal Oats 1/4 in Uran 1519c 344a 1863c NH Oats 1/4 in R2o 118966 312a 1501bc NH Oats 1/4 in H2O + disk 701a 330a 1031a NH Rye 0 in Uran 2321d 292a 2613d NH Rye 1/4 in Uran 2066d 282a 2348d NR Rye 1/4 in R2o 1546c 312a 1858c . Rye 1/4 in R20 + disk 982ab 318a 1300ab NH Rye 1/2 in R2o 1029ab 308a 1337ab NH Small grain seeded 10-8-73 Rye 1/8 an Uran 6736 04 6736 Rye 1/4 in Uran 500b 0 500b Rye 0 in H2O 740b 0 740b Rye 1/4 in H2O + disk 2 326a 0 326a lDry matter. 2 2Values followed by the same letter are not significantly differ.‘ at the .05 percent level, as determined by Duncan's Multiple R ‘ ' Test. 3N0’: harvested. 4Last clipping of winter forage made earlier than in 9-24-73 see LITERATURE CITED Holt, E. C., M. I. Norris and I. A. Lancaster. Production and management of small grains. forage. Texas Agricultural Experiment Stati. 13-1082. Matocha, I. E. 1972. Production of wheat-ryegrass Coastal bermudagrass grown in association as fected by rates and sources of nitrogen. Texas ricultural Experiment Station PR-3015. I Matocha, I. E., Myron McCartor and Bill Ott. 191' Effect of various sources of nitrogen fertilizer forage yields of wheat-ryegrass. Texas Agricultu Experiment Station PR-2877. I McCartor, M. M., and Wayne Taylor. 1971. Whe: ryegrass pasture for beef cattle production in Texas, PR-2974. In I. K. Riggs, et al., Beef ca research in Texas, 1971. Texas Agricultural Ex iment Station Consol. PH-2963-2999. Appendix 1PPENDIX TABLE 1. CLIMATIC DATARELATING TO ‘WINTER PASTURE EXPERIMENTS AT OVERTON 1970-71 / 1971-72 1972-73 1973-74 30-year average R1 ATz AMT3 MT4 R AT AMT MT R AT AMT MT R AT AMT MT R AT 4.9 77.9 67.5 50 5.3 76.5 65.2 50 5.0 79.6 68.7 47 6.9 75.6 65.9 52 2.6 78.3 11.0 63.5 51.6 35 1.3 69.5 57.3 44 7.5 64.5 53.5 41 6.5 67.9 56.5 35 3.1 68.5 1.2 52.8 39.8 22 2.6 55.4 42.3 29 5.0 48.3 38.5 28 4.9 60.5 49.0 33 4.1 55.7 ubtotal and y-Average 17.1 64.7 53:0 9.2 67.1 54.9 _ 17.5 64.1 53.6 18.3 68.0 57.1 9.8 67.5 3.2 53.6 41.9 20 5.9 52.8 43.4 29 3.2 42.5 31.3 4 17 4.0 47.1 32.9 18 4.6 49.2 0.33 49.3 36.4 19 7.2 45.7 33.7 14 5.3 40.9 30.5 9 7.8 43.4 34.2 16 4.3 47.7 4.1 48.9 36.0 14 .5 51.3 39.4 16 2.9 46.6 35.5 17 1.6 50.0 35.7 18 3.8 50.8 0.61 54.6 40.9 20 2.0 60.0 46.3 26 7.7 55.9 41.8 33 3.5 62.3 50.3 28 3.8 57.0 0.78 63.7 50.8 31 1.5 66.3 53.6 37 9.3 60.4 50.8 29 3.4 64.5 50.8 32 4.8 65.7 ifbtotal and . Average 9.02 54.0 41.2 17.1 55.2 43.3 28.4 49.3 38.0 20.3 53.5 40.8 21.3 54.1 1.7 70.2 58.6 41 1.5 71.1 58.0 47 1.5 70.1 58.3 42 4.3 74.9 64.9 50 5.7 73.6 0.96 82.0 69.5 63 5.2 78.9 67.3 50 12.4 77.0 66.8 57 3.7 74.8 64.1 50 3.4 81.2 2.2 82.5 71.4 56 2.8 79.3 68.6 55 4.0 81.8 71.3 65 0.62 80.5 68.0 64 3.5 84.2 2.2 78.1 67.5 56 1.7 81.4 69.0 62 1.1 79.1 66.3 58 3.4 79.5 68.3 62 2.6 84.3 Rainfall, in inches. Average temperature. fil-li/erage’ minimum temperature. fijjinimum temperature. term averages for Longview; all other data obtained from the Tyler weather station. ti . w; 11 The Texas Agricultural Experiment Station, ]. E. Miller, -Director, College Station, Texas 2 1/5 M——8-75 n‘ H’