Metering of Lupins Through a Pneumatic Seeder

Summary

Tests were conducted by the Alberta Farm Machinery Research Centre (AFMRC) to determine if pneumatic seeders could be used to seed lupins. Seed number per unit mass and seed density were determined. Metering distribution uniformity and seed damage using a Case IH 8500 air drill was measured for Primorski and Ultra lupins. Uniformity of distribution across the width of the machine ranged from 5.63 to 7.60 per cent. Varying the metering rate from 84.1 to 174.2 kg/ha (75.0 to 155.2 lb/ac) had no significant effect on distribution uniformity. Reducing fan speed from 4000 to 2800 rpm did not effect distribution uniformity. No seed damage occurred because of the fluted roller metering systems. Average crackage was found to be 0.463 and 2.549 per cent for the Primorski and Ultra lupins for the air delivery system, respectively. Crackage results for the Primorski lupins indicated less seed damage in the air delivery system than the Ultra lupins.

Introduction

The AFMRC in conjunction with the Alberta Agriculture Region One Special Crops Group initiated a project to determine metering rates and seed damage caused by an pneumatic seeder when seeding Primorski and Ultra lupins. All testing was completed on a Case IH 8500 air drill.

Tests were conducted using standard AFMRC test procedures for pneumatic seeders.

Seed Counts

Seed counts were determined for the Primorski and Ultra lupins. Results indicated that the Primorski and Ultra lupins have and average seed count of 3410 and 2808 seeds/kg (1546 and 1270 seeds/lb), respectively.

Seed Density

Seed density was determined using a 0.5 litre volume container and scale. Results indicated the Primorski and Ultra lupins have an average density of 730.31 and 748.92 g/L (58.55 and 60.05 lb/bu), respectively.

Metering

Lupin metering rate calibration for the Case IH 8500 air drill was completed. Seed metering rate tables for lupins were not available from the manufacturer. Tests were done by weighing Ultra lupins metered over a measured time out of the Case IH 8500 metering system. The Case IH 8500 air drill was equipped with a ground driven fluted roller meter. The Case IH 8500 metered seed out of a tank into a venturi feed housing and then into primary air lines which carried the seed to seven distribution headers. Seed was then separated into 11 secondary lines and delivered to ground openers. Metering rate was adjusted by a hand lever which increased or deceased the amount of meter exposed to the seed. Top, middle and bottom settings for metering gates were also available and set depending on the size of the seed metered. For the lupins, the top metering gate setting was used. Calibration with Primorski lupins was not completed. Sample tests indicated that metering rates for Primorski lupins were within 2 per cent of the Ultra lupins metering rates. Calibration results for the Ultra lupins are illustrated in Figure 1. Appendix I (pdf file) contains the metering test results.

Figure 1. Ultra Lupin Metering Calibration for Case IH 8500 Air Drill.

Comparing lupin metering rates and manufacturers seed charts indicated that lupin metering rates where similar to wheat and soybean metering charts for the fluted roller metering system used on the Case IH 8500 air drill. The results are illustrated in Figure 2.

Figure 2. Lupins vs. Case IH 8500 Air Metering Charts

Uniformity of Distribution

Tests to determine the uniformity of seed distribution across the width of the air drill were completed. Tests were completed to determine if fan speed and metering rate affected distribution uniformity. Uniformity was measured at different air flows (fan speeds) and metering rates. Complete uniformity of distribution test results are located in Appendix II (pdf file).

The coefficient of variation (CV) was used to rate uniformity distribution. The CV is the standard deviation of application rates from individual outlets expressed as a per cent of the average application rate. A low CV represents uniform application whereas a high CV indicates non-uniform application. An acceptable variation for seeding grain or applying fertilizer is a CV value not greater than 15 per cent. CV’s of 5 per cent are typical for most seeding equipment presently marketed. Previous testing done on the Case IH 8500 using Laura wheat indicated CV’s ranging from 6.50 to 7.00 per cent. Tests on Tobin canola resulted in CV’s ranging from 6.90 to 7.50 per cent. CV’s for tests on Radley peas ranged from 8.45 to 10.55 per cent.

Effect of Fan Speed and Metering Rate on Uniformity

Fan speeds of 2800 and 4000 rpm were used. The manufacturer suggested a fan speed of 2800 rpm be used for lentils and canola. A fan speed of 4000 rpm was recommended for all other crops listed by the manufacturer. The manufacturer’s seed chart which lists recommended fan speeds is located in Appendix III. Fan speeds had little effect on the uniformity of distribution of the lupins, see Table 1. For example, at fan speeds of 2800 and 4000 rpm, the CV’s at a distribution metering rate of 98.1 kg/ha (87.5 lb/ac) were 6.85 and 7.04 per cent, respectively.

The metering rate did not significantly affect the uniformity of distribution across the machine width. Seeding rates of 84.1 to 174.2 kg/ha (75.0 to 155.2 lb/ac) were used. Increasing the seeding rate from 84.1 to 174.2 kg/ha (75.0 to 155.2 lb/ac) slightly decreases the CV of distribution from 7.60 to 5.63 per cent. Table 1 outlines the CV’s at different metering settings and air flows (fan speeds).

Table 1. Uniformity of Distribution CV’s.

Meter Setting	Variety	Seeding Rate		Fan Speed	CV
		kg/ha	(lb/ac)	rpm	%
14	Primorski	84.1	(75.0)	2800	7.60
14	Ultra	80.5	(71.8)	2800	6.58
18	Ultra	101.8	(90.8)	2800	6.63
18	Primorski	98.1	(87.5)	2800	6.85
22	Primorski	115.3	(102.9)	2800	7.05
22	Ultra	121.0	(108.0)	2800	6.31
32	Ultra	174.2	(155.4)	2800	5.63
18	Primorski	98.6	(87.9)	4000	7.04
18	Primorski	99.2	(88.5)	4000	7.58
18	Ultra	104.1	(92.9)	4000	7.03

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Seed Crackage

Crackage samples were taken at the fluted roller meter. Crackage samples were also done once the seed was delivered through the air delivery system at the openers.

For metering crackage samples, seeds were metered at 101 kg/ha (91 lb/ac). Samples of seed taken after the metering system indicated no visible damage to the seed. Crackage analysis of seed run through the metering system indicated an average crackage of 0.36 and 0.31 per cent less than the control samples taken for the Primorski and Ultra lupins, respectively.

Samples were taken at the opener of four hoses of the air delivery system for the Primorski and Ultra lupins at a meter setting of 18 or seeding rate of 101 kg/ha (91 lb/ac). Average crackage was found to be 0.463 and 2.549 per cent for the Primorski and Ultra lupins, respectively. Crackage results for the Primorski lupins indicated less seed damage in the air delivery system than the Ultra lupins.

Table 2. Crackage Test Results.

Seeding Rate		Gate Setting	Type	Fan Speed	Control Crackage	Average % Sample	Average % Difference From Control
kg/ha	(lb/ac)			rpm	%
101	(91)	Middle	Ultra	Meter	5.85	6.57	0.715
114	(102)	Top	Ultra	Meter	5.41	4.08	-1.335
101	(91)	Top	Primorski	Meter	4.76	4.40	-0.360
101	(91)	Top	Ultra	2800	2.98	5.04	2.695
101	(91)	Top	Ultra	4000	2.64	2.70	2.403
101	(91)	Top	Primorski	2800	3.40	3.16	-0.243
101	(91)	Top	Primorski	4000	2.62	3.30	0.683

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A single test was completed to determine the effect of gate setting on crackage. Ultra lupins were metered at 101 kg/ha (90 lb/ac) using the middle gate setting. Crackage was measured to be 0.715 per cent higher than the control when the middle gate setting was used. Crackage tests with the meter gate set at the top indicated a crackage of -0.360 per cent of the control. Using the middle gate setting caused a 0.715 per cent higher crackage than the top gate setting.

Conclusions

From the tests on the Case IH 8500 air drill the following conclusions can be drawn:

1. The fluted roller metering system of the Case IH 8500 air drill caused little or no damage to the Primorski or Ultra lupins.
2. The air delivery system of the Case IH 85 air drill caused a maximum of 2.7 per cent crackage to the seed at a metering rate of 101 kg/ha (91 lb/ac).
3. The uniformity of distribution of the lupin seed by the Case IH 8500 air drill ranged from 5.63 to 7.60 percent and was considered acceptable.
4. Fan speed and metering rate did not affect uniformity of seed distribution.
5. Metering rate testing of lupins indicated that manufacturers metering calibration charts were similar for wheat and soybeans (density = 2700 seeds/lb).
6. Metering of the Ultra lupins using the middle gate setting rather than the top gate setting caused a 0.715 per cent higher average crackage.