SEPTEMBER 1962 ting Equipment and Practices for Cotton ‘\ ‘_, l» Summary and Recommendations Equipment development and planting practice tests for cotton were conducted on the High Plains over a 13-year period. Equipment studied included the planting row profile, seed-furrow openers, seed- firming wheel and covering devices. Planting prac- tices, such as depth of lister furrow, depth of covering over seed, time of planting, rate of seed and type of seed, were studied. All studies were initially con- ducted on fine sandy loam soils at Substation No. 8, Lubbock, Texas. Later equipment tests were made on loamy fine sand in Terry county and on clay loam soils in Swisher and Hale counties during the last 5 years of the study. The planting furrow or lister furrow should be deep enough to reach moisture adequate to germi- nate seed and insure seedling emergence. Deep- furrow plantings slowed emergence and frequently resulted in thinner stands when precipitation occurred before and during the emergence period. The plateau-planter profile prevented the silting-over of the seed row by heavy washing rains, which was ex- perienced frequently with lister-planter profiles. The use of the plateau planter has reduced the necessity for replantings and has given the highest seedling emergence and best stands. Planting high on the bed gave the second highest emergence and stands. A chisel-furrow opener, 3/4 inch wide and shielded adequately and shaped to drop the seed to the bottom of the seed furrow, gave excellent results on the three soil types. A modified stub runner worked equally well on clay loam soil. Poorer emergence was ex- perienced with the conventional stub runner, and the wear on the knife edge was severe in sandy soils. The seed-furrow opener should be set to cut a trench deep enough into the firm soil behind the lister bottom to permit the covering of seed with 2 inches of soil. The use of a lx 10-inch rubber-tired wheel to firm the seed into moist soil at the bottom of the seed furrow resulted in faster emergence and bet stands under drying conditions. Small scrapers tached to the sides of the seed-firming wheel el' nated excessive buildup of sticky soil on the side the wheel. Covering devices that place a 2-inch deep l soil cover over the seed are recommended. Sh fishtail drags attached at the seed-firming wheel . were satisfactory in friable soils. A harrtfw-t device covered well, but caught crop residue, w interfered with proper covering. Soil covering the seed should not be pressed I the surface in loamy fine sand and fine sandy l g soils; however, surface pressing on clay loam I results in faster emergence and better stands. rubber-flap press wheel mounted on a planter t’ not build up with sticky soil when used for press‘ simultaneously with planting. Seed should be c ered to a depth of 11/2 to 2 inches. Delinted seed produced earlier emergence -A better stands. Delinted seed also were easier handle and meter, and they caused fewer stoppa in the seed tube and the narrow seed-furrow open J - Seeding rates of 20 pounds of chemically delin! seed per acre were adequate to give good emerge and stands for top yields, high harvesting efficie and good weed control. A population of less t’ 20,000 plants per acre reduced yields and harves ' efficiencies. Yields decreased progressively as po lations increased over 50,000 plants per acre. Cotton may be planted successfully after i‘ minimum soil temperature at an 8-inch depth a’ ages 60° F. or above for the l0 days preceding pl ing. Plantings after this temperature occurred I higher emergence percentage and a shorter emerg t period. This guide permits plantings when favora weather prevails earlier than is normally rec‘ mended by date alone. a im;$»l¢|—b.nnn-l4;__4h_a Contents Summary and Recommendations ............................ -- 2 Depth of Covering ______________________________________ __ P" Introduction ................................................................. -. .5 Covering Devices ------------------------------------------ i i S db d P t_ y Pressing of Soil Cover ................................ .. i ee e repara ion ................................................... .- o _ A planting Equipment 5 Planting Practices -------------------------------------------------------- ' E Pr€parati0n of Planter 5 Rate of Seeding ---------------------------------------------------- _ """""""""""""""""""""""""""""""""""""" " _ * Planting ROW Profile __________________________________________ u 5 Type of Seed-..’ ..................................................... SQQd-fUITQW Opgnerg ___________________________________________ __ 8 Tlm€ of Planting """""""""""""""""""""""""""""""" "_ Segdfirming Whgd _____________________________________________ __ 9 Acknowledgments ......................................................... .. Covering of Seed .................................................. -- l0 References ...................................................................... .. g Planting Equipment and Practices for Cotton on the High P|ains E. R. Holekamp, E. B. Hudspeth, R. F. Colwick and L. L. Ray* LANTING COTTON TO A UNIFORM STAND is of primary importance for high yields, high harvesting effi- ciency and good weed control. A cotton stand of uniform spacing with a desirable number of plants per acre is the goal of every mechanized farm. Thin and skippy stands reduce yields and increase mechan- ical harvesting losses and stoppages caused by large branchy plants (2, l9). Such stands permit the growth of weeds, which necessitates control practices to pre- vent the occurrence of grass and weed trash in mechanically harvested cotton (4, 6). Planting cotton in deep lister furrows increased cotton losses with mechanical strippers (8) and pickers (17) because more bolls were close to the ground. The establishment of a desirable cotton stand depends on cultural practices, weather, soil moisture, soil temperature, disease, seed vigor and many factors other than the planting operation itself (16). The planting operation, therefore, should be executed with care, precision and the best known techniques. This bulletin presents and summarizes the results of investi- gations in the Texas High Plains on planting equip- ment and on practices to improve cotton stands and to minimize replantings. Planting to a stand also reduces operating costs such as seed, thinning and early weed control. Among weather hazards confronting the estab- lishment and maintenance of cotton stands in the High Plains are heavy rains and hail, drying hot winds, blowing soil covering the cotton seedlings, unseasonally low temperatures. Each of these condi- tions must be considered in order to obtain satis- factory stands and to reduce replantings. Replant- ings, especially in late May and June (1) delay the crop and decrease yield, thereby decreasing farm income. .A summary and analysis of rainfall at Lubbock, Texgs (5) show that precipitation during the cotton- planting period reaches a peak in the latter part of May, with an overall average precipitation of 2.76 inches for May. The frequency of rain is high; more than four rains for May can be expected for 4 out of 5 years (5) . A briefljrainfall expectation summary ‘fkespectively, agricultural engineers, Agricultural Engineering Research Division, Agricultural Research Service, U. S. Depart- ment of Agriculture, and Substation No. 8, Lubbock, Texas; leader, Cotton Mechanization Investigations, AERD, ARS, USDA, State College, Mississippi; and assistant agronomist, Substation No. 8, Lubbock, Texas. for May (8) from a 41-year record at Lubbock follows: 67.8 percent of the time at least one rain of 1/2 inch or more. 44.0 percent of the time at least two rains of 1/2 inch or more. 32.9 percent of the time at least three rains of 1/2 inch or more. 9.9 percent of the time at least four rains of 1/2 inch or more. 3.2 percent of the time at least five rains of 1/2 inch or more. These data show that the chances of 1/2-inch rain- fall or more after planting and before emergence in May are high; therefore, the hazards of rains crusting the soil and retarding cotton seedling emergence should be considered. Allowances also should be made for the other extreme-no precipitation with hot dry winds—which results in the need to protect seedlings from injury by blowing sand. For many years the latter consideration had more influence on planting practices than the former. Cotton was planted in deep lister furrows to “get down to mois- turei” and to protect the young seedlings from blowing san . Figure 1. Line diagram adjustment of planter equipment. Lines are drawn at 20 or 19-inch centers on the concrete to represent the rows and the middles for 40 and 38-inch row widths, respectively. These narrow lines can then be used to adjust the planter so that share point, seed-furrow opener, seed- firming wheel and covering devices are centered on the row. This same diagram can be used to set listers and cultivators. 3 1»115(§11£4 Figure 2. Typical row profiles obtained in tests from t’ to bottom, plateau planter, high or flat planting, wide, shallo furrow and deep lister furrow. Figure 3. Plateau-profile planter consisted of modifi lister bottom, disks on each side to cut furrows 2 to 3 inc deep and to leave a raised bed l0 inches wide at the to narrow-shielded chisel seed-furrow opener, seed-firming wh and short fishtail drags to cover seed. Figure 4. Lister planter for flat and shallow-furrow pl r ings. Note extension of shares to widen furrow and w A control area. Planter was equipped with narrow-shielded l seed-furrow opener, seed-firming wheel and harrow-type cov 'i device. Figure 5. Typical lister planter for deep-furrow plan’ consisting of lister bottom, narrow-shielded chisel seed-f opener, seed-firming wheel and short fishtail drags to cover Many of these weather hazards were considered observed in the development of new equipment practices during 1949-61. The research develop- I ts were initiated, developed and tested on irri- a fine sandy lo-am soils at the Lubbock statio-n. roved developments and practices were further “d on loamy fine sand and clay loam soils during P6]. Seed bed Preparation A weed-free seedbed, good soil moisture and good _ are important for successful cotton plantings. weral recommendations for management of crop j ues and seedbed preparation are presented by et al. (12) . The final preparation should leave iiiland in good tilth, free of competing weeds and form for proper gaging of planting depths. Listed ill should be prepared precisely on either 40 or 'nch centers with uniform bed heights, side slopes f furrow contour. The use of a line diagram (4) t lister and preplanting weed control equipment I II DAYS AFTER PLANTING Q- E123 DAYS AFTER PLANTING A seeo PRESS-LOOSE sou. COVER a seeo PRESS-PRESSED sou. COVER Y°_ o PRESSED sou. coveR ONLY o LOOSE sou. COVER ONLY PRECIPITATION 4TH DAY 1.25" - I s 0.3a I‘ |o 0.50 ' T ABCD ABCD ABCD ABCD PLATEAU FLAT SHALLOW DEEP - PLANTING eounemeur TESTS , LOAMY FINE SAND—l959 figure 6. Results of planting equipment tests on loamy igsand in Terry county yfor 1959. The stands obtained are as the percent seed planted to produce cotton ‘i. gs. Because of the unfavorable response with pressing iovering soil and not using the seed-firming wheel, only 'ngs employing the seed-firming wheel and a loose soil g 2 inches deep over the seed were used in 1960-61. The jl mean total emergence for combination “A” were 46.8, 138.0 and 32.1 percent emergence, respectively, for the I u, flat, shallow and deep-planting row profiles. is just as important as its use for adjusting planting equipment. Planting Equipment PREPARATION OF PLANTER The mechanical condition of a planter is im- portant for making precise plantings that will produce good stands. Before each planting season, the planter should be thoroughly checked, worn parts replaced, bolts tightened and shares and seed furrow openers sharpened. The row spacing should be set accurately at either 38 or 40 inches for best weed control and efficient mechanical‘ harvesting. ‘ Spacing can be set easily with a line diagram on a concrete floor (4) which can be used later for adjusting the cultivator and the harvesting machine, Figure l. The bottoms of lister-type planters should be straight, equally spaced and parallel so that furrows and beds will be uniform. The seed-furrow opener must be placed on a line through the center of the lister and parallel to the direction of travel. Precise adjustment of the planter row width permits closer cultivation for better weed control because extra widths between sweeps nearest the row are not required for irregularly spaced rows. PLANTING ROW PROFILE Deep-furrow lister planting had been the com- mon practice in the High Plains area until the de- velopment of the shallow-furrow planter attachment by Hudspeth (8, l0) . Since then the trend has been toward shallower furrows with some flat-planting practices. Early tests on irrigated land have shown that lister furrows only 4 to 5 inches deep were superior to planting furrows 6 to 8 inches deep. There TABLE 1. COMPARISON OF PLATEAU AND WIDE SHAL- LOW FURROW PROFILE PLANTINGS DURING THE 1958 PLANTING SEASON, FINE SANDY LOAM SOIL Precipi- Time tation _ Plant emergence Date of Planting for during planting profile initial initial Initial Second Count l0 days after emer- emer- count _ , . 1n1t1al gence gence period Days Inches Percent Percent April 21 Plateau l0 0 20.4 28.2 Shallow l0 0 22.4 28.2 May l Plateau 8 2.05 42.2‘ 53.61 Shallow l0 2.05 17.9 31.7 May 20 Plateau 5 0 59.8 64.7 Shallow 5 0 51.9 44.6 May 26 Plateau 5 0.25 52.1 54.8 Shallow 5 0.25 43.1 48.5 June 2 Plateau 5 0 55.32 55.62 Shallow 5 0 42.8 42.3 ‘Significantly higher at 1% level for this date. ’Significantly higher at 5% level for this date. were fewer losses of stands due to silting-in from heavy rains with the wide, shallow-furrow plantings than with the deep-furrow plantings. Additional planting row profiles were tested during the 1957-61 period on three soil types: loamy fine sand in Terry county; fine sandy loam in Lub- bock county; and clay loams in Swisher and Hale counties to further evaluate their adaptability. The profiles tested were: (l) plateau or profile developed by the Oklahoma Agricultural Experiment Station (13); (2) planting high on the bed; wide, shallow lister furrow, 2 to 4 inches deep; and (4) deep lister furrow, 6 to 8 inches deep. The deep lister furrow was tested only in the loamy fine sand of Terry county. These profiles are illustrated in Figure 2, and planter equipment used are shown in Figures ‘3, 4 and 5. The results for loamy fine sand are pre- sented in Figure 6; fine sandy loam, in Figure 7, and clay loam, in Figure 8. Other planter components, such as the use of seed-firming wheel and the type of soil covering, also were evaluated in these tests I I4 DAYS AFTER PLANTING D 26 DAYS AFTER PLANTING PRECIPITATION 70 L l3 TH DAY 0.45 24TH DAY 044 25TH DAY 0.72 30- Emeassucz, PERCENT 20- SHALLOW FLAT PLATEAU PLANTING EQUIPMENT TESTS LDAM SOIL— I960 Figure 7. Typical results of planting equipment tests in fine sandy loam soils in Lubbock county for 1960. The stands obtained are expressed as the percent of seed planted to produce cotton seedlings. Because of the very unfavorable response with pressing the covering soil in 1958, its use was discontinued in 1959 and only the combination using the seed-firming wheel and loose soil cover was continued in 1960. The 3-year averages of the final combinations were 63.4, 58.0 and 59.1 percent emergence for the plateau, flat and shallow profiles, respectively. 6 during the first and second years. These are d' a cussed under the sections on seed-firming wheel a covering of seed. The deeper planting row profiles generally r duced total emergence, Figures 6 and 8. This tre . was particularly noticeable when rain followed 195 59 plantings in loamy fine sand, Figure 6, and years in the clay loam soils, Figure 8. This w partially caused by the heavier silting over of t seed row. Generally, a delayed emergence a occurred with the deeper plantings. Usually the se was covered with 11/2 to 2 inches of soil. With t deeper planting furrows, wetter and less friable s made it more difficult to cover the seed properly. a The overall performance of the plateau-planti profile was satisfactory on the three soil types. T l ‘ profile was developed to reduce replantings neces tated by silting-over from heavy rains (13). t . profile’s capability was clearly demonstrated in t’ I May l, 1958, planting which was followed by a 2-in 5 rain on May 7, Table l. The heavy rain silted 0v e I 8 DAYS AFTER PLANTING C] I9 DAYS AFTER PLANTING A NARROW SHIELDED CHISEL OPENE I B MODIFIED STUB RUNNER 60- PRECIPITATION IT __1 6TH ozwggg: f I ,2 5o _ I8 . LLI "l a, "' I-IT _ I m o f, so w (I LU 2 w 20 IO A B A B A B PLATEAU FLAT SHALLOW PLANTING EQUIPMENT TEST CLAY LOAM s0u_- I960 a Figure 8. Results of planting equipment tests in clay I soils in Swisher and Hale counties for 1960. The stands ob are expressed as the percent of seed planted to produce i, seedlings. Because of the favorable response to both the _ firming wheel and pressing of the cover soil during 1957-59, ‘ these combinations were continued in 1960 with a comp of seed-furrow openers. The 1958-60 averages for combin employing the narrow-shielded chisel opener, seed-firming and pressed soil cover were 53.3, 43.3 and 35.3 percent eme ; for the plateau, flat and wide shallow furrow profiles, spectively. _ , Figure 9. A comparison of lister furrow and plateau profile plantings after a 3-inch rain 0n June 2, 1959. The plantings on left were made with a lister planter on May 29, and seedling cotton was covered with silt; note only several cotyledons are showing the seed row, creating a crusting condition at the critical period of emergence. Seedling emergence for the plateau planting was almost double that for the shallow-furrow planting; both plantings were made on May 1. The protection of seedlings from silting- over is further illustrated in Figure 9. The absence of precipitation plus drying winds and soil blowing did not cause failure of plantings "in these tests. Several plantings during 1960-61 when little or no precipitation occurred and hot dry weather 'ljprevailed during the emergence period gave satis- factory stands. This indicates that the problems of soil drying and soil blowing are not increased by the a plateau profile. The plateau-profile plantings were significantly better than either the flat or shallow furrow on the loam soil. This was due, in part to shallow seed covering caused by the collapse of gage yheels and by difficulties in adjusting the linkage m. “W furrow. This planting had to be replanted. Right, cotton planted with plateau planter, May 29. Silt washed into the side {Qurrows and the seedlings were not silted over. Photos were taken at Substation No. 8. which attaches the planter to the tractor while plant- ing the flat and shallow profiles. The sand-holding ability of the plateau profile under blowing condi- tions was good, Figure l0. The furrows on both sides of the seed row held large quantities of loose sand just as they do when heavy rains occur. The best cotton seedling emergence was obtained with the plateau profile on the three soil types. The next best stands were obtained with flat or high plant- ings and poorest emergence was obtained with the deep furrow profile. The general trend of delayed and reduced seedling emergence occurred as the depth of lister furrow increased; therefore, the listing furrow should not be deeper than necessary to reach adequate moisture for good germination and emergence. Difficulties in maintaining straight rows occurred with the use of the plateau planter. The disks must Figure l0. Left, sand deposited in the plateau-profile plantings; right, the deep lister furrow plantings. Notice the covering seedlings in the deep furrow. The sand was moved from the left for both plantings. The plateau plantings were adjacent to unplanted field and held considerable sand deposits with minimum of seedling covering. The deep furrow row was the ‘lilifiirteenth row in from the unplanted field. Both photos were taken 22 days after planting in Terry county, May 1960. TABLE 2. COMPARISON OF NARROW CHISEL SEE FURROW OPENER WITH SEED-FIRMING WHEEL A STANDARD LISTER PLANTER WITH SHOVEL OPEN ON FINE SANDY LOAM SOIL Emergence 0f cotton seedling Conventional lister Narrow-shielded chise Year planter with shovel opener with seed- . opener and drag 5 firming wheel and g covering i}: drag covering l ————Percent——-— 1950 87.8 91.2 1951 50.6 62.7 1952 44.6 50.8 1953 41.5 62.41 Average 56.1 66.8 ‘Significantly higher at 1% level for 1953. Figure l1. Stabilizer on plateau planter to minimize side 33ft of Planfer fr“?! ijiPfggaiitfif (if sighs in uneven of the seed germinated and produced seedlings wh s or occasional y nv n e 8' the narrow-shielded chisel was used, Table 2. Anoth advantage of the narrow-shielded chisel opener is t decrease in the width of the seed row, Figure l, which is desirable for subsequent mechanized cultur practices. be carefully adjusted for depth and angle to avoid unequal sidedraft. A stabilizer, Figure ll, helps to overcome sidedraft caused by the occasional drift off the center of the beds. , A comparison of seed-furrow openers in clay 10a SEED-FURRQW QPENERS soil demonstrated that the narrow-shielded chisel a The type of seed-furrow opener used 0n the lister the modified stub runner resulted in about equa or plateau-type planters should be selected for resist- gOOd COIIOH emergence, WhiCh W35 tlistinctly '_§i' ance to wear in the abrasive sandy soils. In addition, than that 0f the standard stub-runner opener, Ta r the opener must be adequately shielded to hold the p 3. The stub runner is modified by the addition p. furrow open so the seed will drop to the bottom of a steel wedge behind the knife edge to spread a8 firm the bottom of the furrow into a Figure l- the seed furrow. This modification works equally well on the curv The narrow-shielded chisel opener, Figure 14, runngr Op€ner_ developed by Hudspeth (8, 10) produced better stands than the wide, shovel openers found on conventional The results of the tests over the years have sho planters of the past. A 4-year average of results for that the use of the narrow-shielded chisel seed-furr; tests on this development shows that l0 percent more opener gave better stands than other types and Figure 12. The nar- row-shielded chisel opener produced a narrower drill row of cotton (left) than the shovel type opener. The narrow drill is only 11/2 inches wide and is more desirable for other mechanical operation than the wider row 21/2 inches wide. LE 3. COTTON EMERGENCE AS AFFECTED BY TYPE SEED-FURROW OPENER ON CLAY LOAM SOILS. TESTS CONDUCTED WITH SEED-PRESS WHEEL Seed t0 produce cotton seedlings H 451mm“, 1959 tests 1960 tests i 0P6l1¢f 7 days 17 days 8 days 19 days after after after after planting planting planting planting mow-shielded — — — — — Percent — — — — — chisel 19.4 41.4 12.9 40.9 9w fied stub runner 19.9 43.2 14.2 42.3 ‘Qllb runner 17.0 37.8‘ ‘ficantly lower at 5% level. d excellent wearing qualities in sandy and sandy am soils. The use of a modified stub-runner opener ve as good to slightly better stands than the chisel ner in clay loam soils. The use of a knife or ‘t slicer on the underside of the lister share of e lister-type planter has been useful in cutting evious crop residues and trash and in reducing the lodging of trash on the chisel opener. EED-FIRMING WHEEL The development and use of the 1 x 10-inch bber seed-firming wheel to press seed into moist il before covering came early in planting equipment odifications by Hudspeth (l0) , and its use has been ._s'dely accepted. The use of the seed-firming wheel g ve faster emergence and usually a more dependable nd in years when no precipitation occurred. In tests comparing plantings with and without e seed-firming wheel, the average emergence at first 3®unt was 15.2 percent with the seed-firming wheel iind 10.6 percent without the wheel on the loamy fine nd, 52.8 percent with and 48.5 percent without on fine sandy loam and 37.1 percent with and 29.2 per- I I2 DAYS AFTER PLANTING El 24 DAYS AFTER PLANTING PRECIPITATION 8Q a2 "m DAY 0.45" 2am: 0.14" NI O 0'8 O EMERG ENCE . P ERCENT .9. o: O O 0 I6 32 48 64 TOTAL WHEEL WEIGHT, LBS. SEED WHEEL PRESSURE TESTS LOAM SOIL - I960 Figure 14. Results of the seed-firming wheel pressure tests for 1960. cent without on the clay loam. These percentages demonstrated a definite trend of increased emergence before the post-planting precipitation masked the differences. For example, in 1957 on clay loam soil, the emergence was 43.4 percent in 7 days for plantings with the seed-firming wheel, compared with 20.3 per- cent without the firming wheel. On the sixth day of planting, 1.40 inches of precipitation occurred, and the emergence increased to 50.0 per cent of the seed Figure l3. Comparison of seed-furrow openers, two narrow-shielded chisel openers (left), modified stub runner and, conven- "final stub runner (right). The stub runner was modified by welding a steel wedge behind the leading knife and extending the iifiields back. The chisel openers are 3/4 inch wide at point, the shields extend to the point, then expand to a 1-inch width and are lined slightly at the rear. Long shields are required to insure seed reaching bottom of the seed furrow. Figure 15. Loading of 1-inch wide by 10-inch diameter zero pressure hollow rubber-tired seed-firming wheel. The load was measured statically with a scale attached at the wheel axle. The load as shown is 52 pounds. planted without the wheel and to only 45.0 percent with the wheel. This 2-week delay in emergence can reduce yields of late plantings, as was experienced in this test. The average emergence at the second counts with and without the seed-firming wheel were 34.6 percent with and 30.9 percent without on the loamy fine sand; 57.6 percent with and 54.7 percent without in the fine sandy loam; and 44.7 percent with and 48.8 percent without in the clay loam soil. These results indicate a general increase of stands using the seed-firming wheel even during wet seasons, except for the clay loam soil. The advantages of using the firm- ing wheel under drying conditions on clay loam soils were evident. The effects of varying pressures applied with the seed-firming wheel are shown in Figure 14. The tests were conducted with dead weights for the wheel, Figure l6. Small scrapers mounted on the side of the seed-firming wheel (left) prevent the excessive buildup of soil (' Such scrapers have been used on extensive acreage and observed not to interfere with opera y; The scrapers are made of thin sheets of high carbon steel mounted at a 28.5 degree angle from the side of the wheel. See F's interfering with proper operation. 15 for improved scraper attachment. 10 Figure 15. The actual maximum pressure per squ inch was not determined readily because the ze pressure tire flattened irregularly and increased contact area on a flat surface as the weight was creased. These tests also showed the usefulness the seed firming in that the zero-pressure planti had the lowest percentage of emergence. The r- performance was 32 pounds total weight in 1960 a 17 pounds in 1961. The curvilinear regressions cal lated for each test and periodic stand count sh maximum emergence for 48 and 52 pounds t0 weight, whereas the actual weight was l7 to 32 poun A total Wheel weight of 3O to 35 pounds is conside desirable. l In moist soils, the soil stuck to the sides of firming wheel. This difficulty was eliminated » installing scrapers on the sides of the wheel, Fi l6. Wheels equipped with these small scrapers ha. been used successfully for several years on numer experimental plots and on approximately 80 a of planting. COVERING OF SEED . Covering of seed planted at the proper dept and with proper compactness influences the rate emergence, earliness and the total emergence. a of these three factors has been observed in tests duri the 13-year period. " Depth of Covering The depth at which seed is covered influen the time required for emergence and the total em gence obtained. Early results of this work were ported by Hudspeth (ll). Covering seed with more than 2 inches of i delayed emergence and decreased the final emergen Figure l7. Covering the seed with less than 2 inc i‘-_-_.A@-‘-4-_ iigii- __ :u&esno£.1P:no s nlT OI O I 8 DAYS AFTER PLANTING C119 DAYS AFTER PLANTING A- FUZZY SEED B-. MACHINE DELINTED 0- ACID DELINTED -F (I @ ¢ C ¢ I A I I I : - I 20- I0- 0. ABC ABC ABC ABC II 2U 3U 4U COVERING DEPTH OF SEED I954 Figure 17. Depth of soil covering the seed test results. The results were consistent over the 4-year test period. Each year the early emergence for the 2-inch depth was significantly better than the 1-inch or 4-inch depths. generally resulted in decreased emergence because of the drying of the seed and of the soil around the seed. After 1955, all test plantings were made t0 cover seed at a maximum depth of 2 inches and a minimum of 1% inches. To obtain good stands, the seed-furrow openers must be set to cut a furrow of sufficient depth into the moist soil behind the lister to cover the seed - with 2 inches of soil. Covering Devices Seed covering 2 inches deep can be obtained "readily with covering devices, Figures 3, 4 and 5. The barrow drag reported by Hudspeth (l0) covers the seed well and tills the soil to provide a loose soil eogiir, Figure 4. Its main disadvantage is that trash or old stalks and stems from the previous crop lodges in the spikes and results in poor covering. The short drags shown in Figures 3 and 5, adapta- tions of the fishtail drags, are pivoted at the seed- firming wheel axle. These covering devices are self- cleaning and perform well in a friable soil. They do not, however, cover as well as desired in sticky, wet soils. No specific tests were made comparing the two covering devices, but all of the plateau plantings - compared in Figures 6, 7 and 8 used this fishtail type Figure 18. Pressing the soil covering the seed with a zero pressure tire. This pressing was found detrimental to seedling emergence on loamy fine sand and fine sandy loam soils but helpful on clay loam soils. of covering device. The performance was acceptable under all of the conditions encountered. Pressing of Soil Cover Pressing the soil which covers the seed is a practice that may or may not increase emergence, depending on the type of soil encountered. Pressing the soil over the seed row with a zero-pressure rubber tire, Figure 18, caused heavy crusting; it decreased emergence on the loamy fine sand and fine sandy loam soils but increased emergence on clay loam soils. The average first-count emergence comparing the loose soil cover and the pressed soil cover were, respectively, 14.3 and 11.6 percent on the loamy fine sand, 44.8 and 20.8 on the fine sandy loam and 30.6 and 37.3 on the clay loam. These averages for the second counts were 32.3 percent for the loose soil and 33.4 percent for the pressed soil on the loamy fine sand, 55.5 and 31.6 percent on the fine sandy loam and 39.3 and 43.5 on the clay loam. Extreme crusting experienced with the pressed soil cover in the 1958 tests on fine sandy loam soil reduced emergence to two-thirds of that for the loose soil cover. The first-count emer- gence on the loamy fine sand indicated the same detrimental effect from pressing as was also found on the fine sandy loam. An overall increase of emer- gence was experienced by pressing the covering soil on clay 10am soils. As the clay content of soil in- creases, some pressing of the soil cover becomes desir- able. The division point at which this operation becomes advantageous has not been determined. Pressing the soil covering the seed on clay loam soils should be done at the time of planting to reduce the number of field operations. The zero-pressure rubber tire was not practical for this operation be- cause of excessive sticking of soil to the tire. The flap-rubber-press wheel developed by Smith and Wilkes (18) was useful in overcoming this difficulty, Figure 19. As many as 5 acres were planted with ll Figure 19. Pressing the soil covering the seed with rubber- flap wheel on the clay loam soils. This type of wheel permitted the pressing of covering soil while planting without sticking to the wheel. these flap-press wheels without the buildup of soil which was previously experienced with the zero- pressure tires. Planting Practices RATE OF SEEDING Plant population was studied extensively to de- termine maximum yields and harvesting efficiencies. This type of study for the High Plains was reported by Ray et al. (15). The best seeding rate for yield was determined to be from 15 to 25 pounds of seed per acre for irrigated land. These seeding rates re- sulted in an average plant population of 33,500 to 50,000 plants per acre or an average plant spacing of 4.7 and 3.1 inches apart, respectively, for the lower and higher seeding rates on 40-inch row widths. Table 4 summarizes plants per acre for 38 and 40-inch row widths for various plant spacings. The conclusions from the study by Ray et al. (15) were: (1) “A planting rate of 15 pounds per acre will give satisfactory plant population in most years, but increasing this rate to 20 pounds per acre will give insurance against replanting in years when emer- gence is poor. Other factors which should be con- sidered are seed type, seed germination, soil type and weather conditions.” and (2) “Planting rates of about 20 pounds per acre should give high stripper harvest- ing efficiency, good yields and a minimum probability of replanting.” Seeding rates of 15 pounds per acre would plant 60,000 to 75,000 seeds per acre, and the 20-pound rate would plant 80,000 to 100,000 per acre, depending on variety or seed size. When emergence is low, or around 25 percent of seed planted, the 15-pound rate would produce 15,000 to 18,750 seedlings per acre, a thin but adequate stand; the 20-pound rate would result in 20,000 to 25,000 plants per acre, a good 12 TABLE 4. PLANT SPACING IN INCHES, PLANTS PE FOOT OF ROW AND THE NUMBER OF PLANTS PE’ ACRE FOR 40 AND 38-INCH ROW WIDTHS Plants Inches Plants per Plants per per foot between acre, 40-inch acre, 38-inch of row plants rows rows 12 1.0 156,816 165,048 l0 1.2 130,680 137,540 8 1.5 104,544 110,032 6 2.0 78,408 82,524 4 3.0 52,272 55,016 3 4.0 39,204 41,262 2 6.0 26,136 27,508 1 12.0 13,068 13,754‘ 0.5 24.0 6,534 6,877 0.3 40.0 3,920 4,126 stand. When emergence is 50 percent or higher, t plant populations are doubled or higher. From t, it can be concluded that the 20-pound rate is adequa for the small seed varieties. It may be desirable , increase this rate for large seed varieties if the ger 1 nation test shows a low percentage of germinatioi a TYPE OF SEED t The effect on emergence of seed type—fuzzy ( run), machine delinted and chemically delinted see has been studied. Results reported by Hudspeth ( “ and Jones et al. (12) stated that “satisfactory stand can be obtained from either fuzzy or delinted cotto a seed. There is a trend toward the use of delint seed because of less seed tube stoppage, greater -. of handling, faster germination and greater unifo I ity of stands.” The faster germination of delint seed as related to depth of covering is shown y Figure 17. Approximately the same seeding rates i required to obtain comparable stands. Chemica, delinted seed averages 5 to 6 percent more seed ‘p pound than fuzzy seed ~ TIME OF PLANTING The earliest feasible plantings are desirable maximum production on the High Plains. Gene recommendations have set May l0 as the ideal I ginning date for planting cotton. A recently c0 pleted study (7) has shown that soil temperatures c’ be a valuable guide to timely cotton plantings, w'f due consideration of weather forecasts. The foll ing recommendations were made from this study f, using soil temperaturesas a guide to timely cott planting: “Cotton planting should be delayed until average minimum soil temperature of 60° F. at 8-inch depth is reached for a 10-day period. Foll - f ing soil temperature as a guide results in earl plantings more often than following optimum pla ing dates. This guide should be used only to establ' the earliest possible time for planting. Soil perature is not a determining factor for late-sea a i plantings. ottonseed planted at recommended soil tem- res should not be covered with more than 2 of soil for quick emergence, and proper plant- jctices and equipment should be used for best Heavy soil-crusting rains are detrimental t0 j emergence and it is advisable to delay plantings such rains are in immediate prospect. Long- weather forecasts also are valuable considera- * at planting time. With a 10-day average i um soil temperature of 60° F. at the 8-inch j as a planting guide, seedlings can be expected rge in 9 days or less, whereas emergence from gs in colder soils may require 13 to 15 days. seed rotting will be reduced greatly by planting per soil temperature. Daily soil temperatures can be determined V’ when the sensing element of the thermometer ed at the recommended 8-inch depth in the I of the preplanting bed. A thin-stemmed meter such as a dial thermometer with a bi- Tic sensing unit can be inserted easily into the 7' the desired depth. The minimum soil tem- l, res should be taken daily between 7:30 and m. and recorded for at least l0 days.” Acknowledgments i his research was conducted cooperatively by 5.? exas Agricultural Experiment Station, Substa- :No. 8, Lubbock, Texas, and the Agricultural l? eering Research Division, Agricultural Research v e, U. S. Department of Agriculture, and is a 'buting project to the Regional Cotton Mecha- on Project S-2. These investigations were con- by Rex F. Colwick during the 1949-50 seasons, . B. Hudspeth during the 1951-56 seasons and f“ R. Holekamp during the 1957-61 seasons. he authors express their appreciation to D. L. '< agronomist emeritus, Substation No. 8, for nce in planning and conducting the investiga- ‘l and to the following manufacturers of farm finery for the loan or gifts of equipment and ‘A used in these studies: International Harvester I. Case Co., John Deere Co., Cline Industries, “ster Mill Co., Kelly Plow Co. and others. References ' bro, J. D., Jr. and L. L. Ray, Performance of Four Cotton arieties in Relation to Planting Date on the High Plains 2f Texas, 1960, Texas Agri. Exp. Sta. Progress Report 2197, uly, 1961. v lwick, Rex F., et alflMeehanization of Cotton Production, j uthern Cooperative Series Bulletin No. 33, June, 1953. l0. ll. 12. 13. l4. 15. 16. 17. 18. 19. Colwick, Rex F., et al., Planting in the Mechanization of Cotton Production, Southern Cooperative Series Bulletin No. 49, February, 1957. Colwick, Rex. F., et al., Weed Control Equipment and Methods for Mechanized Cotton Production, Southern Co- operative Series Bulletin No. 71, April, 1960. Covey, W. G., R. J. Hildreth and E. L. Thaxton, Jr., Rain- fall at Lubbock, Texas, Texas Agri. Exp. Sta. Misc. Publi- cation 211, June, 1957. Garner, Thomas H., Henry D. Bowen and James A. Lus- combe, Effect of Weed Control on Quality of Mechanically Harvested Cotton, The Cotton Gin and Oil Mill Press, September 6, 1958. Holekamp, E. R., _E. B. Hudspeth and L. L. Ray, Soil Temperature-A Guide to Timely Cotton.Planting, Texas Agri. Exp. Sta. Misc. Publication 465, October, 1960. Hudspeth, E. B. and D. L. Jones, Influence of Depth of Planting Furrow on Emergence, Harvester Efficiency and Other Related Factors in Cotton Production on the High Plains, Texas Agri. Exp. Sta. Progress Report 1484, August 1952. Hudspeth, E. B., L. L. Ray and D. L. Jones, The Use of Fuzzy, Machine and Chemically Delinted Cotton Seed for Planting on the High Plains of Texas, Texas Agri. Exp. Sta. Progress Report 1547, February, 1953. Hudspeth, E. B. and D. L. Jones, Planter Equipment Test, Lubbock 1949-53, Texas Agri. Exp. Sta. Progress Report i 1673, April, 1954. Hudspeth, E. B. and D. L. Jones, Emergence and Yield of Cotton as Affected by Depth of Covering Seed. Texas Agri. Exp. Sta. Progress Report 1688, June, 1954. Jones, D. L., et al., Cotton Production on the Texas High Plains, Texas Agri. Exp. Sta. Bulletin 830, April, 1956. Porterfield, J. and E. M. Smith, Development and Test Performance of a New Seedbed for Cotton, Oklahoma Agri. Exp. Sta. Bulletin 449, February, 1955. Ray, L. L., E. B. Hudspeth and D. L. Jones, Influence of Rate of Planting on Seedling Emergence of Cotton Under Crusting Conditions, Texas Agri. Exp. Sta. Progress Report 1415, November, 1951. Ray, L. L., E. B. Hudspeth and E. R. Holekamp, Cotton Planting Rate Studies on the High Plains, Texas Agri. Exp. Sta. Misc. Publication 358, May, 1959. Smith, H. P. and D. L. Jones, Mechanized Production of Cotton in Texas, Texas Agri. Exp. Sta. Bulletin 704, September, 1948. U. S. Department of Agriculture, Agricultural Research Service, Agricultural Engineering Research Division, Un- published data, Annual Report, 1960. Wilborn, Ed, Press Wheel for Sticky Blacklands, Progressive Farmer, February, 1959. Williamson, E. B. and F. E. Fulgham, The Influence of Spacing on Mechanical Harvesting of Cotton, Mississippi Farm Research, Mississippi Agri. Exp. Sta., February, 1956. 13 [Blank Pagfi in Original Bulletin] [Blank Page in Original Bulletin] i’ nun sumac O nu sununons I nu nun LIIOIATOIIIS A wornnm snnous Location oi field research units oi the Texas Agricultural Experiment Station and cooperating agencies ORGANIZATION OPERATION Research results are carried to Texas farmers, ranchmen and homemakers by county agents and specialists of the Texas Agricultural Ex- tension Service 3046i? ,6 KQJQLIPCA yd YOVROIWOLUQ P097855 State-wide Research The Texas Agricultural Experiment Station is the public agricultural research agency oi the State oi Texas. and is one oi the parts oi the A&M College oi Texas. IN THE MAIN STATION, with headquarters at College Station, are 13 su matter departments, 3 service departments, 3 regulatory services an administrative staii. Located out in the major agricultural areas oi Tex 2O substations and 1O field laboratories. In addition, there are 13 cooper stations owned by other agencies. Cooperating agencies include the Forest Service, Game and Fish Commission oi Texas, Texas Prison Sy U. S. Department oi Agriculture, University oi Texas, Texas Technol College, Texas College oi Arts and Industries and the King Ranch. experiments are conducted on farms and ranches and in rural homes. THE TEXAS STATION is conducting about 450 active research projects, -= in 25 programs, which include all phases oi agriculture in Texas. ‘ t these are: Conservation and improvement oi soil Beef cattle Conservation and use oi water Dairy cattle Grasses and legumes Sheep and goats Grain crops Swine Cotton and other fiber crops Chickens and turkeys Vegetable crops Animal diseases and parasit Citrus and other subtropical fruits Fish and game . Fruits and nuts Farm and ranch engineerin Oil seed crops Farm and ranch business Ornamental plants Marketing agricultural prod,“ Brush and weeds Rural home economics A Insects Rural agricultural economi Plant diseases ‘ Two additional programs are maintenance and upkeep, and central se AGRICULTURAL RESEARCH seeks the WHATS. the j WHYS. the WHENS. the WHERES and the HOWS oi i hundreds oi problems which confront operators oi farms ; and ranches, and the many industries depending on ' or serving agriculture. Workers oi the Main Station 1 and the field units oi the Texas Agricultural Experi- » ment Station seek diligently to iind solutions to these . problems. Y