For example, at a target population of 105,000 plants per acre and 85 percent germination, 30-inch rows will need twice the number of seeds per linear foot as 15-inch rows (6 vs. 3 seeds . These results suggest that soybeans compensate for low stands, producing yields that "Wide rows (30-inch) take nearly 25 days longer and 40 days longer to canopy compared to 15-inch and 7.5-inch rows, respectively. The difference in plant structure across four seeding rates is shown in Figure 2. In Sanilac County, 15-inch rows were compared to 30-inch rows. If you counted 191 emerged soybean plants in the 65 feet, 4.1 inches of a single row of 8-inch rowed beans, your fi eld's population is 191,000 plants/acre. Nine studies that compared 30-inch rows and 15-inch rows found similar results, with 15-inch rows holding a 4.0 bu/acre yield advantage. Plant Population. At that time, some weed growth in the hay crop was tolerable. The purple bars indicate the yields from the original soybean stands, the red bars indicate yields from the added soybeans. The results were mixed. Each treatment area was four 30-inch rows measuring 10 feet wide by 30 feet long. Harvested grain yield (corrected to 13% moisture) Year Targeted harvest population 7.5-inch rows 15-inch rows 30-inch rows KEY LEARNINGS These results support those of previous studies.1,2 When planting soybeans in June in 30-inch row spacing in this study, both ROI and overall yield were . Results from 2005 showed no significant impact of either row width (10, 20 and 30-inch) or plant population (73,000, 108,000 and 143,000 plants/acre) on soybean yield. Another critical consideration is the impact that a frost in late May might have had. Across the U.S., narrow rows (less than or equal to 15 inches) out-yielded wide rows (greater than or equal to 30 inches) 69% of the time. I do all of my research with 15 and 30 inch row spacing comparison since the trends shows that drills probably will disappear in the near future. The lowest . When moving production to a narrower row, seeding rate should be decreased. Results from 2005 showed no significant impact of either row width (10, 20 and 30-inch) or plant population (73,000, 108,000 and 143,000 plants/acre) on soybean yield. Disease severity index of soybean plots planted in 30-inch or 15-inch row spacing, at planting populations ranging from 110,000 seeds/acre to 200,000 seeds/acre and treated with Aproach fungicide applied in a conventional program or according to the disease risk model, or not treated. Narrowing rows from 20 to 10 inches boost yields another 2 bushels per acre. The number of plants x 1000 = plant population in plants per acre. Soybean seed cost and potential for decrease in white mold severity drive interest in decreasing seeding rates. Seed drop rates for desired plants per foot of row. To determine stand count on 30" rows it is just like the example above for corn. As emphasis shifted to production for beans . In 2016, Beck's published their 10-year, multi-location EOSR data which showed a return on investment advantage of over $31.09/ A. to planting in 15-inch rows over 30-inch rows. In 2009, the US DA reported that about 85 percent of the corn crop was planted in 30-inch rows or wider. More recent on-farm tests showed that soybeans in 15-inch rows yielded 5 bu/A higher than soybeans in 30-inch rows. Aerial imagery at the Chase County site in 2017 showed less vigor and higher thermal stress in 30-inch row soybeans during the early reproductive growth. While it's not fully understood, scientists know soybeans in 30-inch rows will crowd . Seed Spacing: inches: Row Width: inches : Population: Click "Calculate" for Results Population: Row Width: inches : Seed Spacing: Click "Calculate" for Results Row Spacing. Soybean Board funded a project to investigate five populations seeded with and without an inoculant at five locations across Kentucky. In Indiana, the average yield increase for 15-inch rows was 2.7%. At all locations, inoculant did not have a significant effect on yield. The same planter was used for all treatments at a site: One tool bar was switched off for the 30-inch rows. Figure 3. Skip row soybeans. primary advantage is weed control by both cultivation and chemicals. Conley's work on soybean population and treatments suggests . This calculator figures seed spacing and population. Row width had no effect on lodging severity (Figure 2). 4 plants per foot in 30-inch rows equal approximately 140,000, 105,000, and 70,000 plants per acre (PPA), respectively. In addition, modern drills have much better depth control than older grain drills. Seeding rates were set by adjusting the planter A Genuity® Roundup Ready 2 Yield® soybean product with relative maturity (RM) of 2.4 was planted on 7 May 2012 in 7.5-inch (drilled), 15- and- 30-inch row, and 30-inch twin row systems. Row Spacing. Paul Hermans, an area agronomist for Dupont Pioneer in eastern Ontario, says the plots in the study yielded an average of 62.1 bushels per acre in the 30-inch rows, while the 15-inch rows yielded 60.1 bushels per acre on average. Weeds were . One question kind of going back to that population, right? You do not need to increase your seeding rate if you are using a 15 inch row spacing compared to a 30 inch row spacing. Corn plants are spaced 7.1 inches apart in 20-inch rows at 44,000 seeds per acre, compared to 6.3 inches apart at 32,000 seeds per acre in 30-inch rows, according to Below. Soybean populations in 30-inch rows Bob Battel, Michigan State University Extension - May 1, 2017 Soybean seed cost and potential for decrease in white mold severity drive interest in decreasing seeding rates. Our data also indicates that a stand of 50,000 plants per acre will yield only 13% less than the maximum yield (for additional yield loss based on plant population please refer to the 2006 Purdue University Corn and Soybean . So, over the last two years, Nathan and Larry have been trialing different soybean populations on 15-inch rows on Larry's farm in Washington County, including 90,000, 120,000, 150,000 and 180,000 seeds per acre. Both row spacings were planted with a Case IH 1250 Early Riser planter set up for 30-inch rows. The soybean was a 3.9 maturity and seeded in 15-inch rows at each location by Eugene Lacefield. • Narrow rows (20-inch and twin) produced higher yields than wider, 30-inch rows (Figure 2). In those 2 cultivar years, the 15-inch yield advantage was 1.5 to 2.7 bu/ac. For soybeans planted on 15" rows, you double that distance and measure off 34 feet 10 inches and count the plants. At the third site, however, where soybeans were no-tilled in 30-inch rows, seeding depth had minimum effect on early plant populations, except at the 1.0 inch depth in 2014, when one planter unit had trouble penetrating the soil. Only about 4 to 5 percent of the crop was planted in 15- or 20-inch rows. County Year Crop Trial Type Trial Detail Yield Difference (+/-) Report Scouting Report; Iowa: Washington: 2018: Corn: Plant Nutrition - Fertilizer: Sidedress Hog Manure vs. UANSD By comparison, data from the Dupont Pioneer plots showed a slight yield increase for 30-inch rows. This study was initiated in 2006 to determine the response of corn grown in 15-inch, 30-inch and paired rows 8-inches apart (10-inches apart in 2006) on 30-inch centers at plant populations of 25,000, 30,000 and 35,000 plants/acre. that's bigger than the 2.3 bushel per acre yield bump they achieved when they invested in an intensive program, including fertilizer, inoculants, seed treatment and foliar fungicides on soybeans planted in 30-inch rows. That could explain why early planted stands only had an average yield advantage of 1.9 bushels per acre. Purdue research suggests that a final stand of 80,000 plants per acre (in 30 inch rows) is adequate for achieving 100% of yield . There were no significant differences in the yields when comparing three different seeding rates of soybeans planted in 30-inch rows. SDSU research showed in a small plot study that moving from 30 inch rows to 15 inch rows increased yield up to 20 bushels per acre. Four planters had 15-inch row spacing, two had 22-inch rows and five had 30-inch rows. Optimal plant population (from table 1) Seeding rate Row spacing (inches) 7.5 8 10 15 18 20 25 30 plants/acre seed/acre seed per ft of row to be planted Narrow Rows. Drilled (solid) seeding of soybeans is a continually growing practice in Missouri. In Iowa, similar small yield responses to 15-inch row spacings compared to 30-inch row spacings were observed when grown at comparable populations. Treatments were replicated six times. Row Width Row Length Equal to 1/1000 Acre 20" 26.2 ft. 30" 17.4 ft. 36" 14.5 ft. 38 . For example the population of 75,000 seeds/acre showed a difference of 0.4 bushels between 30 inch and 7.5 inch drilled beans and this difference is 87% likely to be due to chance alone. Soybean planting rate was 90 lb/A throughout this study, but final population varied with years and row spacings. At Beresford the two row spacings gave similar yields ( 70.9 bu/ac for 8-inch vs 70.4 bu/ac for 30-inch) while at Aberdeen the 8-inch row spacing had greater yield than the 30-inch row spacing (62.3 vs 56.0 bu/ac) (Table 1). The benefits to yield and weed control are real," Woodyard says. Two row spacing trials were conducted in 2015. But it's an interesting story, I'll keep it short, but the company switched varieties on him. In comparison, the average row width for grain corn was estimated as 30.4 inches for Iowa, 30.5 inches for Wisconsin and 31 inches for Nebraska. Plant population was 9,100 plants/ac (8.0%) greater in 30-inch row spacing than in 15-inch row spacing. The 15-inch soybean row spacing may have a slight numerical advantage over both 20- and 30-inch row spacing, however, across cultivar-years only 2 of 20 were significantly higher yielding at 15-inch row spacing (Figure 1). The key trick is planting enough seed to end up with 100,000+ plants at harvest. This is probably due to earlier canopy closure in narrow rows that enables more light interception and drives photosynthesis. More than 1 million acres were drilled in 1986, compared to just 300,000 acres in 1979. Pioneer Hi-Bred International, Inc. reported a four percent advantage for 22.5-inch rows versus 30-inch rows in trials conducted from 1991-94 (Paszkiewicz, et al., 1994). Farmers can drastically increase plant populations in 20-inch corn rows compared to 30-inch rows while increasing plant separation. Soybean population. Make several counts in separate sections of the cornfield, figure the average of these samples, then multiply this number by one thousand. The other key discovery is that soybean yield is generally maximized at harvest at 100,000 plants per acre when plants are evenly distributed across the field. Taking stand counts using the traditional method above can be arduous if soybeans are planted in narrow rows, so an alternative method may be more conducive to quickly getting stand count estimates. ADVANTAGE 20s. Experimental plots consisted of 3 rows with a length of 25 feet and replicated 8 times. "We haven't seen a difference in yield between 30- and 15-inch rows." The only disadvantage that Reha has seen with 30-inch soybeans is that the soybeans take longer to canopy. For the examples that you were using, what's the row spacing? "We have no-tilled our beans in 15-inch rows at a population of about 180,000, but have been able to cut back our planting rates to 150,000 with 30-inch beans," Reha says. • Disease pressure was also low in this trial. Figure 1. find the Seeding rate depends on both row spacing and seed size. - Yes, those two charts, those two in that table, the Saginaw site was actually in 30 inch rows and still had significant mold. The results were mixed. "We discovered a trend for both, that as plant population goes up, the yields go up," Reid says. In corn, Licht said corn yields in 15- and 20-inch rows have been comparable with 30-inch rows, with the noticeable benefits coming in high-performing fields. Soybean Populations In 30-Inch Rows. Plant population was 9,100 plants/ac (8.0%) greater in 30-inch row spacing than in 15-inch row spacing. Problem 13.1. Time is of the essence to assess emerging soybean fields to determine the need for interplanting to strengthen stands or replanting weak (e.g., ponded) areas. The lowest . Stand counts were conducted when soybeans were at VE/VC growth stage on June 23 and repeated pre-harvest on October 6 at R7 . In Illinois, 20-inch rows out-yielded 15-inch by only 3.0 %. Although the majority of corn in Minnesota is planted in 30-inch rows, results indicate that a significant number of acres are planted in narrow rows (less than 30 inches wide). "Our data shows a 3- to 5-bushel increase in soybeans from switching to a narrow soybean row configuration such as 15- or 20-inch." Soybeans have a remarkable ability to compensate for low planting populations by increasing branches, nodes, and ultimately, pods. This calculator is designed to help you estimate the number of seed per foot of row. Soybean populations were 158, 143, 111, and 103 thousand plants per acre in 1961, and in 1962 they were 179, 149, 139, and 148 thousand plants per acre in 10-, 20-, 30-, and 40-inch rows, respectively. This graph shows the effects of filling in thin soybean stands (7.5-inch rows) with a 30-inch row planter at V2 soybean (Semmel, Christmas, and Marini, 2002). As a second example, if you drilled soybeans into 8-inch rows (cell D5), you would count the soybean plants in 65 feet (cell D6), 4.1 inches (cell D7) of row. uniform stand of 100,000 plants per acre in drilled and 15 inch rows and 80,000 plants in 30 inch rows will yield 100%. Purdue research suggests that a final stand of 80,000 plants per acre (in 30 inch rows) is adequate for achieving 100% of yield . The same question regarding the effect of reduced populations on soybean yields exists today for farmers switching to narrow-row soybeans. The benefits to yield and weed control are real," Woodyard says. "Full stand" established populations ranging from 70,000 to 140,000 PPA differed in "full-yield potential" by only 5 percent. In some respects, the greater advantage for narrower rows observed in the northern Cornbelt is similar to row spacing effects with soybean. In soybean, the main effect of row spacing was significant. Soybeans are more difficult than corn since there are multiple row width options. Switching from 30-inch rows to 20-inch rows or less boosted yields by an average of nearly three bushels per acre. Population (seed/ac) Row Spacing Moisture % Yield (bu/ac) 125,000 30 13.4 14 125,000 15 13.4 16.7 150,000 30 13.7 18 150,000 15 13 17.1 Wayne County Soybean Population/Row Spacing Study Cooperator: Cherry Research Farm, Rosewood NC Planting Date: June 4, 2013 Harvest Date: November 25, 2013 Variety: DP 6568RR The most recent recommendation from Ohio State University on seeding rates in 30-inch rows is nine seeds per foot of row, or approximately 157,000 seeds per acre. Plot was planted using a two-row, tractor mounted, plot planter. "Soybean yields were up 15 to 20 per cent above average, which tends to favour a 30-inch row I think," Hermans says. "Our data shows a 3- to 5-bushel increase in soybeans from switching to a narrow soybean row configuration such as 15- or 20-inch." That's not to say that soybeans in wide rows couldn't yield higher than soybeans in narrow rows, but they didn't in the first 1,026 times it was tried on North Carolina farms. 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