SPECIAL SURVEY ON MICRO-RATE, 1998
Alan G. Dexter and John L. Luecke
Extension Sugarbeet Specialist and Sugarbeet Research
Specialist, North Dakota State University
and the University of Minnesota,
Fargo.
An extra page was included in the 1998 annual survey of sugarbeet growers to obtain information on the use of the micro-rate in 1998. The micro-rate is Betanex at 0.5 pt/A OR Betamix at 0.5 pt/A plus UpBeet at 0.125 oz/A plus Stinger at 1.3 fl. oz/A plus methylated seed oil adjuvant at 1.5% v/v. Quad 7, a basic blend adjuvant, also was reported on the survey. The normal rate of Quad 7 was 1% v/v. The micro-rate must be applied three or more times at a 5 to 7 day interval starting when the sugarbeet plants are in the cotyledon to early two-leaf stage.
The micro-rate survey was returned by 417 respondents. The micro-rate was used by 64% of the respondents. Total sugarbeet acreage of all respondents was 177,877A or about 25% of the total sugarbeet acreage in eastern North Dakota and Minnesota.
| Method |
Acres reported |
% of total |
| Acres broadcast with micro-rate
Acres banded with micro-rate Acres sprayed by air |
188,157 75,967 84,695 |
54 22 24 |
| Total |
348,819 |
100 |
Table 2. Herbicides used as a part of the micro-rate combinations.
|
Herbicide |
Responses |
Rate less |
Rate more |
|
% of total |
% of respondents |
% of respondents | |
| Betanex/Betamix
Progress Stinger UpBeet Oil adjuvant Quad 7 Assure II Poast Select Prism |
22 <1 20 21 17 4 1 2 9 3 |
8 -- 15 6 23 29 20 8 13 4 |
6 -- 13 19 1 14 20 8 6 9 |
A significant percentage of respondents made modifications to the suggested rates of herbicides and adjuvants that make up the micro-rate (Table 2).
Table 3. Herbicide combinations used in the micro-rate system
| Herbicide
combination |
Respondents that |
|
% | |
| Betanex + UpBeet
Betanex + UpBeet + Stinger Betanex + UpBeet + Grass herbicide Betanex + UpBeet + Stinger + Grass herbicide Betamix + UpBeet Betamix + UpBeet + Stinger Betamix + UpBeet + Grass herbicide Betamix + UpBeet + Stinger + Grass herbicide |
6 22 3 49 <1 6 1 11 |
A grass herbicide was used in the micro-rate by 64% of the respondents (Table 3).
Table 4. Band width for band application of the micro-rate
| Width |
Respondents |
| inches |
% |
| 7
9 10 11 12 14 15 |
8 7 30 45 3 3 3 |
A band width of 10 or 11 inches was the most common among respondents that band applied the micro-rate (Table 4).
Table 5. Spray pressure used for micro-rate application.
| Spray
pressure |
Respondents |
| psi |
% |
| <30
30-39 40-49 50-59 60-69 >69 |
4 9 51 17 7 12 |
Spray pressures reported on the survey varied from 11 psi to 170 psi. The most common pressures were 40 psi at 40% and 50 psi at 15% of the respondents. (Table 5).
Table 6. Sprayer water volume used for micro rate application.
| Water
volume |
Respondents |
| gpa |
% |
| <7
7-9 10-12 13-15 16-18 >18 |
13 22 44 13 5 4 |
Sprayer water volumes reported on the survey varied from 4 gpa to 20 gpa. The most common volumes were 10 gpa at 36% and 8 gpa at 8% of the respondents.
Table 7. Spray speed used for micro-rate application.
| Speed |
Respondents |
| mph |
% |
| <6
6 7 8 9-10 11-15 |
12 32 32 14 8 2 |
Sprayer speeds reported on the survey varied from 4 mph to 15 mph. The most common speeds were 6 and 7 mph each at 32% of the respondents (Table 7).
Respondents were asked if they reduced the number of row crop cultivations because they broadcast the micro rate. Cultivations were reduced by 59% of the respondents, 35% said they still cultivated the normal amount and 6% indicated that they banded the micro-rate.
Table 8. Reduction in number of cultivations due to broadcasting micro-rate.
| Number
of cultivations eliminated |
Respondents who |
|
% | |
| 0
1 2 3 |
38 35 25 2 |
Nozzle plugging from precipitate that forms in the sprayer was a common problem with ground sprayer application of the micro-rate in 1998.
Table 9. Problems with nozzle plugging in the sprayer.
| Response |
Respondents |
|
% | |
| Yes, had a problem
No, did not have a problem All sprayed by air |
45 41 14 |
Table 10. Ranking of the relative severity of the nozzle plugging over all respondents.
| Ranking |
Respondents who had | |
|
% | ||
| No problem
Terrible |
0
1 2 3 4 5 |
0 16 25 16 29 14 |
If we assume that a ranking of 3, 4 or 5 indicates a significant problem with nozzle plugging, then about 26% of all micro-rate users had a significant problem (45% with a problem and 59% of these ranked the problem as a 3, 4 or 5).
Respondents were asked to list anything that reduced or eliminated nozzle plugging with the micro-rate.
Table 11. Things that reduced or eliminated nozzle plugging.
| Item |
Respondents | |
|
Number |
% | |
| Clean sprayer frequently
Use warm water Use Quad 7 Add a grass herbicide Use a different oil adjuvant Use ammonia Premix the UpBeet Nothing worked Change screens Reduce agitation Change from Betanex to Betamix Change mixing order Reduce water volume Spray immediately after mixing Use injection system Use hollow cone nozzles |
31 27 23 16 16 14 14 13 9 6 5 5 5 4 4 2 |
15 13 11 8 8 7 7 6 4 3 3 3 3 2 2 1 |
Responses to nozzle plugging questions were separated by spray volume, sprayer pressure, sprayer speed and acres of sugarbeet per respondent.
Table 12. Sprayer pressure and nozzle plugging.
|
Ranking of problem | ||||||||||
|
Problem with plugging? |
No problem |
Terrible | ||||||||
| Sprayer
pressure |
Yes |
No |
All air |
0 |
1 |
2 |
3 |
4 |
5 | |
| psi |
- - - - - - - - % of respondents - - - - - - - - - |
- - - - - - - - - - - - - % of respondents - - - - - - - - - - - - | ||||||||
| <30
30-39 40-49 50-59 60-69 >69 |
22 40 52 58 50 41 |
12 55 46 42 50 59 |
67 5 1 0 0 0 |
0 0 0 0 0 0 |
9 25 17 14 12 18 |
18 0 28 27 12 36 |
18 38 14 14 25 9 |
46 25 24 36 38 18 |
9 12 17 9 12 18 | |
No obvious relationship between nozzle plugging and sprayer pressure was seen in Table 12.
Table 13. Spray volume and nozzle plugging.
|
Ranking of problem | ||||||||||
|
Problem with plugging? |
No problem |
Terrible | ||||||||
| Sprayer volume |
Yes |
No |
All air |
0 |
1 |
2 |
3 |
4 |
5 | |
| gpa |
- - - - - - - - % of respondents - - - - - - - - - |
- - - - - - - - - - - - - % of respondents - - - - - - - - - - - - | ||||||||
| <7
7-9 10-12 13-15 16-18 >18 |
31 60 47 61 30 25 |
22 40 52 39 70 75 |
47 0 1 0 0 0 |
0 0 0 0 0 0 |
9 11 24 12 0 50 |
26 32 20 24 33 0 |
13 25 16 6 0 50 |
39 25 22 41 33 0 |
13 7 18 18 33 0 | |
The percentage of respondents who had no problem was greater with spray volumes over 16 gpa (Table 13). Perhaps the larger nozzles and screens used for high water volume reduced the amount of plugging.
Table 14. Sprayer speed and nozzle plugging.
|
Ranking of problem | ||||||||||
|
Problem with plugging? |
No problem |
Terrible | ||||||||
| Sprayer
speed |
Yes |
No |
All air |
0 |
1 |
2 |
3 |
4 |
5 | |
| mph |
- - - - - - - - % of respondents - - - - - - - - - |
- - - - - - - - - - - - - % of respondents - - - - - - - - - - - - | ||||||||
| <6
6 7 8 9-10 11-15 |
21 59 50 53 50 60 |
31 41 49 43 50 40 |
48 0 1 3 0 0 |
0 0 0 0 0 0 |
27 7 18 31 11 0 |
33 24 24 19 11 67 |
0 20 15 19 33 0 |
27 37 29 25 11 0 |
13 12 15 6 33 33 | |
No obvious relationship between nozzle plugging and sprayer speed was seen in Table 14.
Table 15. Acres of sugarbeet per respondent and nozzle plugging.
|
Ranking of problem | ||||||||||
|
Problem with plugging? |
No problem |
Terrible | ||||||||
| Sugarbeet
acres |
Yes |
No |
All air |
0 |
1 |
2 |
3 |
4 |
5 | |
|
- - - - - - - % of respondents - - - - - - - - - |
- - - - - - - - - - - - - % of respondents - - - - - - - - - - - | |||||||||
| <251
251-500 501-750 >750 |
40 48 43 52 |
50 38 40 35 |
10 15 17 13 |
0 0 0 0 |
17 17 16 14 |
10 31 21 33 |
20 15 16 14 |
30 25 47 19 |
23 12 0 19 | |
No obvious relationship between nozzle plugging and size of sugarbeet operation was seen in Table 15.
Table 16. Application method and nozzle plugging.
|
Ranking of problem | ||||||||||
|
Problem with plugging? |
No problem |
Terrible | ||||||||
| Application
method |
Yes |
No |
All air |
0 |
1 |
2 |
3 |
4 |
5 | |
|
- - - - - - - - % of respondents - - - - - - - - - |
- - - - - - - - - - - - - % of respondents - - - - - - - - - - | |||||||||
| Broadcast
Band |
55 56 |
44 43 |
1 1 |
0 0 |
17 13 |
26 24 |
16 20 |
27 31 |
16 13 | |
Nozzle plugging was very similar between broadcast sprayers and band sprayers. (Table 16).
Respondents were asked to rank their overall satisfaction with the micro-rate.
Table 17. Ranking of satisfaction with the micro-rate over all respondents.
| Ranking |
Respondents who used micro-rate | |
|
% | ||
| Totally unsatisfied
Completely satisfied |
0
1 2 3 4 5 |
0 2 3 13 53 29 |
The ratings of satisfaction were separated by sprayer pressure, spray volume, sprayer speed and acres of sugarbeet per respondent.
Table 18. Sprayer pressure and satisfaction rating.
|
Ranking of satisfaction | ||||||
| Sprayer | Totally unsatisfied | Completely satisfied | ||||
| pressure |
0 |
1 |
2 |
3 |
4 |
5 |
| psi |
- - - - - - - - - - - - - - - - - - - - - - - - - - % of respondents - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |||||
| <30
30-39 40-49 50-59 60-69 >69 |
0 0 0 0 0 0 |
0 0 2 5 0 0 |
2 5 2 5 6 4 |
17 15 12 18 6 7 |
62 45 54 45 50 56 |
19 35 31 26 38 33 |
No obvious relationship between sprayer pressure and satisfaction rating was seen in Table 18.
Table 19. Spray volume and satisfaction rating.
|
Ranking of satisfaction | ||||||
| Spray | Totally unsatisfied | Completely satisfied | ||||
| volume |
0 |
1 |
2 |
3 |
4 |
5 |
| gpa |
- - - - - - - - - - - - - - - - - - - - - - - - - - % of respondents - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |||||
| <7
7-9 10-12 13-15 16-18 >18 |
0 0 0 0 0 0 |
1 0 1 4 10 0 |
1 2 2 14 0 0 |
13 10 14 14 10 25 |
57 56 55 46 40 25 |
28 31 28 21 40 50 |
No obvious relationship between spray volume and satisfaction rating was seen in Table 19.
Table 20. Sprayer speed and satisfaction rating.
|
Ranking of satisfaction | ||||||
| Sprayer | Totally unsatisfied | Completely satisfied | ||||
| speed |
0 |
1 |
2 |
3 |
4 |
5 |
| mph |
- - - - - - - - - - - - - - - - - - - - - - - - - - % of respondents - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | |||||
| <6
6 7 8 9-10 11-15 |
0 0 0 0 0 0 |
1 1 3 0 0 0 |
1 4 4 3 0 0 |
15 13 13 7 22 0 |
58 50 51 60 39 80 |
25 31 29 30 39 20 |
The degree of satisfaction tended to increase as the sprayer speed increased (Table 20). Perhaps the people who were in a hurry liked the convenience of broadcasting the micro-rate.
Table 21. Acres of sugarbeet per respondent and satisfaction rating.
|
Ranking of satisfaction | ||||||
| Sugarbeet | Totally unsatisfied | Completely satisfied | ||||
| acres |
0 |
1 |
2 |
3 |
4 |
5 |
|
- - - - - - - - - - - - - - - - - - - - - - - - - - % of respondents - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | ||||||
| <251
251-500 501-750 >750 |
0 0 0 0 |
3 1 2 0 |
4 3 2 2 |
13 14 10 15 |
56 53 60 40 |
24 29 25 42 |
No obvious relationship between size of sugarbeet operation and satisfaction rating was seen in Table 21.
Table 22. Application method and satisfaction rating
|
Ranking of satisfaction | ||||||
| Application | Totally unsatisfied | Completely satisfied | ||||
| method |
0 |
1 |
2 |
3 |
4 |
5 |
|
- - - - - - - - - - - - - - - - - - - - - - - - - - % of respondents - - - - - - - - - - - - - - - - - - - - - - - - - - - - - | ||||||
| Broadcast
Band |
0 0 |
2 1 |
3 1 |
13 9 |
49 59 |
33 30 |
Satisfaction with band spraying was slightly higher than with broadcast spraying (Table 22), probably because band spraying is less costly than broadcasting.
Perhaps the best indication of the overall satisfaction with the micro-rate is that 97% of the respondents who used the micro-rate in 1998 indicated that they intended to use the micro-rate again in 1999.