Effectiveness of Double Shoot Openers for Applying Anhydrous Ammonia

Date: February 1996
Term: 1 year
Status: Completed
Researcher: R. Maze, Alberta Farm Machinery Research Centre
SaskCanola Investment: n/a
Total Project Cost: n/a
Funding Partners: n/a

Project Summary

By the mid 1990s, many farmers on the Canadian prairies were changing from conventional farming to direct or one-pass seeding systems. Researchers at the Alberta Farm Machinery Research Centre at Lethbridge conducted a one-year project in 1995 to see how different soil openers placed anhydrous ammonia and urea with the seed using 14 different double shoot openers at nine Alberta sites. Generally, yields of canola and canola emergence were lower when placing anhydrous ammonia with the seed compared to granular urea, although on most sites the differences were not statistically significant. In general, as fertilizer rate increased emergence tended to be reduced, however as expected, yields increased with higher fertilizer rates. Overall there were no trends between different types of openers.

By the mid 1990s, many farmers on the Canadian prairies were changing from conventional farming to direct or one-pass seeding systems. With one-pass seeding, farmers had the choice of a single shoot or double shoot system to place the fertilizer during seeding. Even with the double shoot system that separates seed and fertilizer in the seed row, the major concern was how much of the required fertilizer could be applied at seeding without crop injury due to nitrogen burning. New improved double shoot openers on air seeders and air drills had greatly reduced the concern.

Researchers at the Alberta Farm Machinery Research Centre at Lethbridge conducted a one-year project in 1995 to evaluate the application of nitrogen with double shoot openers. Fertility and opener experiments were developed to see how different soil openers placed anhydrous ammonia and urea with the seed. Crop injury, assessed at crop emergence, and yield responses were measured. The fertility experiment included four double shoot solid openers placing 0, 56, 112 and 168 kg/ha (0, 50, 100 and 150 lb/ac) of actual nitrogen in the form of urea or anhydrous ammonia fertilizer.

Canola, barley and wheat were seeded at nine sites across south, central and northern Alberta. The opener experiment was repeated at three sites and included 14 different double shoot soil openers placing urea and anhydrous ammonia at 0, 56 and 168 kg/ha (0, 50 and 100 lb/ac) while seeding barley and canola.

Figure 1. Source: AFMRCGenerally, yields of canola, barley and wheat were lower when placing anhydrous ammonia with the seed compared to granular urea, although on most sites the differences were not statistically significant. The yield reductions were attributed to the loss of anhydrous ammonia during and after seeding. In most conditions tested, crop injury was not significantly different between anhydrous ammonia or granular urea, although canola emergence tended to be lower when using anhydrous ammonia as compared to urea.

Researchers also did some preliminary testing of ammonia loss at the opener at Vegreville, Alberta. The results showed an insignificant amount (<0.01 percent) of ammonia was lost for the openers tested at the point of injection. Further anhydrous ammonia testing was recommended to determine the amount of ammonia lost over time for a variety of openers.

All of the double shoot openers tested safely applied up to 168 kg/ha (150 lb/ac) of actual nitrogen of both anhydrous ammonia and granular urea fertilizer for canola, barley and wheat. In general, as fertilizer rate increased emergence tended to be reduced, however as expected, yields increased with higher fertilizer rates. Days to crop maturity were also effected by higher fertilizer rates, with high rates lengthening days to maturity. However, days to maturity were not effected consistently between sites.

All of the openers were able to place the seed and fertilizer so that in most cases, the bands were kept from being mixed. Some mixing was found, particularly between canola and anhydrous ammonia in certain sites. Although the type of opener and the rate of fertilizer did result in some significant differences in terms of yield and emergence of canola and barley depending on the site and soil conditions, overall there were no trends between different types of openers.

Full Report PDF: Effectiveness of Double Shoot Openers for Applying Anhydrous Ammonia