Using Common Drills, Fertilizer Spreaders, and Carriers to Plant Difficult Seeds

Transcription

1 Using Common Drills, Fertilizer Spreaders, and Carriers to Plant Difficult Seeds Introduction Common drills are the usual tool for planting clean, hard, relatively heavy, free-flowing seeds such as wheat, rye, soybeans, alfalfa, and cowpeas. Many people refer to this equipment as simply wheat drills. Difficult seeds are the fluffy, bulky, chaffy, awned, rough-husked ones that are relatively light and flow out of a common grain drill poorly, if at all. They include seed of Old World bluestems (such as plains and caucasian), native range grasses (such as big bluestem, little bluestem, indiangrass, and switchgrass), crabgrass, rescuegrass, and to a lesser extent ryegrass, fescue, bromegrass, orchardgrass, and wheatgrass. In this publication, they are referred to as bulky seed. The equipment industry has specially engineered drills and other planters that distribute and plant bulky seeds. They often are too expensive to be purchased by many producers and are not readily obtainable in some regions, but they sometimes can be rented from various organizations such as the Natural Resource Conservation Service (NRCS) and farmers' cooperative store support services. These drills are more common in the western range country of the United States. These special drills seldom have a fertilizer box or liquid fertilizer attachment, which is unfortunate because much of the soil in Oklahoma and the southeastern United States is phosphorus deficient. Grasses get a boost from receiving a banded nitrogen-phosphorus or complete fertilizer like or down the row with the seed at planting. Drills and other planters that can accommodate fertilizer are an asset in early stand development and good early production, as are certain common drills that are managed correctly. This information targets primarily the small to medium unit operated by managers who want to do their own planting. Without special equipment, we are relegated to adapting what we have or what is available, usually common drills or broadcast techniques. We will focus primarily on common drills and certain fertilizer spreaders and summarize years of experience with seeding techniques.

2 Seed Carriers When common drills and fertilizer spreaders are used, a carrier is blended with the bulky seed. This mix then can be dispersed through the grain or fertilizer box. A good carrier adds weight, increases bulk density, and separates the seed, therefore making it flow so it can be planted with a drill or fertilizer spreader. If dry fertilizer is the carrier, its weight and hardness help keep the drill boots free of bulky seed trash. If the carrier is the proper dry fertilizer, it is also initial seedling food. Carriers successfully used include dry granulated and pelleted fertilizer, cracked grain, dry coarse washed sand, pelleted or granulated lime, soybean meal, hard seeds such as wheat, and dry screened sawdust. All carriers must be dry. Acceptable dry fertilizer grades are the best choice because they act as a carrier and provide plant nutrition. Most of this information pertains directly to seed and fertilizer mixtures, but other carriers may be substituted for the fertilizer if it is not needed or desired. Carriers other than fertilizer have more problems. In our region and the southeastern United States, nitrogen and phosphorus are almost always needed; therefore, and complete blended grades of fertilizer such as , , , and are good choices that are commonly available. Many other blends work well. Grasses can respond for many years to phosphorus supplied in the grades listed above. To avoid equipment problems, use a fertilizer that has been screened to remove clods. If nitrogen and phosphorus are not needed, can be used strictly as a carrier because it is the least expensive and least likely to cause seed germination impairment or seedling damage. The fertilizer as a carrier performs better if it has irregularly shaped and sized granules and pellets and contains some dust because the combination, which the complete grades have, decreases problems with seed and fertilizer separation. Flow of the fertilizer depends on the equipment. Grass seed germination is unaffected if the mix is made and distributed the same day or very soon thereafter, which is well documented with plains bluestem seeds (Dalrymple, 1979) and in unpublished research with crabgrass seeds. The same is true for legume seeds. In mixes fewer than six hours old, dry fertilizer had minimal effect on the legume seed inoculant (Pelinoc-Pelgel) or early seedling growth (Evers, 1986). After six hours, the fertilizers that suppressed germination the most were potassium, phosphorus, and nitrogen, in that order.

3 Carrier: Seed Ratios and Planting Rates Bulky seed to fertilizer bulk ratios must be considered. Most bulky and less bulky mixes disperse well when the seed-fertilizer ratio does not exceed 1 : 20 (5 pounds of seed to 100 pounds of fertilizer). For less bulky seeds such as those of bromegrass, crabgrass, fescue, orchardgrass, ryegrass, and wheatgrass, more seed and less fertilizer can be used. A mixture of up to 20 pounds of seed to 100 pounds of bulk-weight fertilizer usually flows well with the less bulky seeds. When extremely bulky, rough-husked, or awned seeds are used, a lower ratio of seed to fertilizer, near 1 : 40 (5 pounds of seed to 200 pounds of fertilizer) may be needed. In all of these cases, the weight of the mixture equals the planting rate per acre. For example, 5 pounds of seed per acre and 100 pounds of net-weight fertilizer per acre would be applied for a total of 105 pounds per acre. The bulk density of the seed-fertilizer mixture can be greater or less than that of wheat seed, which is 60 pounds per bushel. The relative bulk density is part of what influences equipment planting rate settings and mixture flow from the equipment. For example, a planting of 5 pounds of less bulky crabgrass seed to 100 pounds of fertilizer ( ) per acre has a higher bulk density than wheat at about 65 pounds per bushel, 20 pounds of less bulky bromegrass seed to 100 pounds of fertilizer per acre has a bulk density of about 54 pounds per bushel because of the higher volume of lowweight seed, and 20 pounds of very bulky native grass seed to 200 pounds of fertilizer per acre has the lowest bulk density of the three, or about 45 pounds per bushel. Because of bulk density and other factors, it is best to calibrate the drill with the mixture to be used so initial planting will be somewhat accurate. Drill manuals and other publications explain how to do that (Griffith, n.d.). To start calibration, set the drill or broadcast seeder for a readily flowable, less bulky seed-fertilizer mixture such as the crabgrass-fertilizer mixture at about 75 percent of the setting for wheat at the same rate per acre. Test and adjust the setting as needed. Settings for this type of mixture may range from near 75 percent to about 100 percent of the same setting for wheat seed. Planting a mixture like that of the bromegrass example above may require a trial drill setting of 180 percent that for wheat at the same rate. The native grass mixture example may require a trial drill setting of 250 percent that of wheat at the same rate. The bulkier the seed and the lower the relative bulk density, the higher the relative setting must be. Mixture distribution by individual drills is incredibly variable. Relative bulk density, fertilizer and seed characteristics, humidity, and other factors also influence distribution. Calibration is important, but actual field experience is more important because drills may behave differently during actual use than they do during calibration. Keep precise planting records of equipment settings, rates per acre, and planting conditions for future use. It is wise to indelibly record this information on the underside of the drill or fertilizer hopper lid for easy reference.

4 Making the Seed-Fertilizer Mixture The best way to mix seed and fertilizers is to have a fertilizer blending plant do it. Some plant managers can be rather irritable about that request, but most in our region now readily comply. If you cannot have the mixture prepared for you, use a cement mixer (figure 1), which can be rented and holds 100 to 300 pounds of fertilizer. The machine takes one to three minutes to mix the materials well. Transfer the mix into the planter being used. Figure 1. Using a portable cement mixer to fieldmix bulky seed and dry fertilizer for planting with a common fluted feed grain drill Figure 2. Hand mixing bulky seed & fertilizer in a trough The most inefficient way to mix is by hand. Put the fertilizer in a container such as a no. 2 tub, calf trough, or barrel bottom, add the necessary seed, and stir with a tool (hoe) or by hand, but be sure to use gloves. Mixing 50 to 100 pounds of material at a time works well (figure 2). Pouring seed and fertilizer into the container simultaneously aids in mixing. Besides bulky seeds, small grains and other crop seeds that flow readily can be planted in a seedfertilizer mix. Hard seeds or less bulky seeds do not need to be mixed with the fertilizer: simply put in alternating layers of seed and fertilizer, starting with seed on the bottom of the hopper. Layers of 50 pounds each of wheat or other hard-seeded crops and fertilizer distribute very well. The seed and fertilizer mix as they move through the drill box in a funnel pattern and out of the feed openings (figure 3). Because of their characteristics and bulk density, these mixtures flow differently than pure, hard seed. For example, to distribute a fifty-fifty mix of wheat and fertilizer, the calibration setting is usually near 175 percent that for wheat alone. The ratio of seed to fertilizer can be adjusted to the

5 desired rates per acre, but the layering should be uniform and as consistent as feasible. Planting Management Control planting depth according to crop requirements and field conditions. When seed are broadcast planted in a row on top of a good seedbed and row openers are run above ground or shallowly, it is often necessary to disconnect the rod or other parts at the drill clutch and engage the clutch by hand to get seed flow. The boots may crimp when the row openers run above the soil line. Figure 3. A schematic diagram of flow characteristics of a layered flowable seed and dry fertilizer combination coming out of a drill box or other planting equipment

6 Seedbed Preparation or No-Till Methods Seeds are usually planted in a recently finished, fresh, firm seedbed before a rainfall (figure 4). Seedbeds should be firm enough to leave a 1/2 - to 1-inch depression as you walk and should be free of deep cracks and large clods that can cover seeds too deeply when rain closes the cracks and smooths the soil. Dragging or rolling (cultipacking) the seedbed before planting firms it. Homemade rollers work well and tandem operations reduce inputs (figure 5). Next, drill or broadcast spread the seed-fertilizer (or other carrier) mix. If a roller (or cultipacker) is available, roll the area after planting to cover some seed lightly, leave some on or very near the soil surface, and increase seed-soil contact. For uniform coverage, be sure the seedbed is in excellent condition before dispersing the seed mix. Basic equipment that can band a fertilizer with the seed can be used in no-till operations (Dalrymple, 1999). Think ahead: Where is that seed going to be after you and the first pounding rains are through? Most grass seeds should be on or just under the soil surface or no deeper than 1/2 inch. The same techniques as above can be used with common drills in no-till, chemical fallow, or lowtillage methods to plant seeds in pasture residue or stubble. If you use no-till planting methods and common grain drills, plan for the disk or hard point furrow openers to have shallow penetration; plant after a rain when the soil surface is softer, put more tension on the furrow opener springs, or drive two to three miles per hour (Dalrymple, 1999). Use the proper seeds, including any of the small grains, sorghum forages (sudangrass), millets, and many perennial pasture grasses, to help ensure a successful stand. Some experimentation may be necessary. Figure 4. A well prepared seedbed with no large clods, ready for planting small seeded grasses, legumes, and other crops Figure 5. Pulling a homemade roller behind a common fluted feed drill while planting a bulky seed and dry fertilizer mixture

7 What Drills? The very best drills for this technique are those with a fluted seed dispersal mechanism in the drill box (figure 6). Manufacturers include John Deere, IHC (International Harvester Company), and IHC- Case. Some very old models work well (figure 7). "Rolling wheel" and "cup" seed dispersal mechanisms and many plastic wheel mechanisms perform poorly or not at all. Test your equipment to determine its abilities. Here is some food for thought: In the Southern Plains and south central United States, good used grain drills with fluted seed-feeding mechanisms can be purchased at farm sales or from dealers for $100 to $1,000. The equipment can be converted to make a special planter capable of rowed or broadcast plantings. If the operator wants only a good precise broadcaster, the boots and rowing mechanisms can be removed. Then removable large pipes or hoses can be installed under each drill box seed hole to direct the seed-fertilizer mix in a "splatter band" row on the soil surface. The equipment is then either a broadcaster or row planter, depending upon the use of the tubes. Figure 6. Fluted feed mechanism in the bottom of a drill box Figure 7. An old model of a fluted feed John Deere drill

8 Using Fertilizer Spreaders The seed-fertilizer mixtures can be planted with essentially any dry fertilizer spreader, including old drill-box-type fertilizer spreaders that have metal agitators in the hopper (figure 8): Ezy-Flow, Judson, IHC, and John Deere are among those who sold them. Models 10 feet wide and narrower are available from Gandy Equipment Company (528 Gandria Rd., Owatonna, MN 55060, [507] ; figure 9). Any equipment dealer should be able to obtain spreaders from Gandy. Figure 8. An old model of a drill box fertilizer spreader being used to plant a bulky seedfertilizer mixture The rotary spreaders (spinner spreaders) are available almost universally. These machines easily spread the seed mixture in about 20- to 30- foot-wide patterns. However, the dry fertilizer will be thrown two to three times farther than lighter seed. To reduce this effect, set the fertilizer-rate gate to about one-third to one-half the usual rate, e.g., 30 to 50 pounds per acre versus 100, and take one-third to one-half the normal swath width, e.g., 20 to 30 feet per swath versus 60. With this procedure, the seed pattern overlaps somewhat and the volume of fertilizer is doubled to get the total rate per acre. The actual swath or pattern depends on the seed and fertilizer spreader and the rates it can apply. Many commercial-sized fertilizer spreaders will not apply the low rates listed and higher rates must be used. Check the seed pattern and adjust the machinery accordingly for full seed coverage. Spinner spreaders never provide a perfectly uniform spread. Where many cash crops are grown, airflow fertilizer spreaders are often available and are excellent for spreading seed-fertilizer mixtures (figure 10). They provide a uniform wide pattern and are often the most precise broadcasters available commercially, and the operator can quickly cover many acres. Always spread the mixture on calm days or those with a gentle breeze and take advantage of crosswinds so the patterns will overlap better. Be cautious about mixing big batches and spreading over large areas: the mix may separate some, and you may need to remix the last of it with a scoop.

9 Figure 9. A Gandy Co. drill-box-type seedfertilizer spreader in operation (photograph courtesy of Gandy Co.) Figure 10. A modern airflow fertilizer spreader being used to plant a bulky seed-fertilizer mixture on a good seedbed

10 Cleaning and Maintaining the Planter Some operators will not put fertilizer in the drill's grain box. Others, after trying this technique, state they would never plant seed-fertilizer combinations any other way. The major key to equipment longevity is cleaning and protecting the machinery after use. Be fanatical about emptying the drill or planter each day. Clean it thoroughly at the close of the job as follows: (1) wash it thoroughly inside and outside with a pressurized water hose and lots of water and let it dry; (2) rerinse all parts with a 10 to 30 percent household ammonia solution in water to help neutralize fertilizer acid residue (use a compressed air [pump-up] hand sprayer and let the unit dry); and (3) coat all fertilizer-contaminated parts with diesel, kerosene, a mixture of one part oil and three parts diesel, or spray-can oil, covering all joints and seams. Almost any type of seed, with some variation of the basic technique, can be planted as described (figure 11). Figure 11. Stand of a native grass mixture achieved by mixing the extremely fluffy seed with dry fertilizer and planting the mix through a fluted-feed common grain drill

11 References Dalrymple, R. L Low-input overseeding. Ardmore, Okla.: The Samuel Roberts Noble Foundation. Pub. no. NF-FO Dalrymple, R. L Plains bluestem. Ardmore, Okla.: The Samuel Roberts Noble Foundation. Pub. no. FO 15. Evers, G Fertilizer-clover seed contact time on clover emergence and growth. Forage Research in Texas, 1986 (Texas Agricultural Experiment Station) CPR-4499: Griffith, C. A. Calibration of planting and applicating equipment. Ardmore, Okla.: The Samuel Roberts Noble Foundation, n.d. 16 pp. Acknowledgments We credit Dooly Barlow, Grant Huggins and Cara Wallace for reviewing and editing this manuscript by The Samuel Roberts Noble Foundation, Inc.