Community
Education > Assessment of Sweet Corn IPM Adoption in New England &
Mid-Atlantic States: Are We There Yet?
By C.S. Hollingsworth, W.M. Coli and B.A. Szala
Abstract
Questionnaires regarding general farming practices and specific
IPM practices, were sent to 1318 farmers purported to grow sweet corn
in seven states (CT, DE, ME, MD, MA, NJ, PA). A total of 832 questionnaires
(63%) were returned: 502 respondents grew sweet corn. The response rate
(17%) allows statistical inference at the 95% confidence level, with a
sampling error of +/- 5%.
Adoption of IPM-related practices by respondents is summarized, for example:
82% reported application of pesticides to sweet corn; 76% calibrate sprayers
annually or more often; 30% use pheromone or blacklight traps; 37% use
university-provided pest thresholds.
Respondents' adoption of a comprehensive IPM system was measured using
the elements and point system from the Massachusetts Crop-Specific IPM
Definitions. Of the sweet corn growers surveyed, only 3% attained 70%
of the possible IPM practice points, the requirement for IPM certification
in Massachusetts. Thus, if this measurement of high-level IPM adoption
is used, the federal goal of 75% of U.S. crop acreage under IPM appears
distant.
Introduction
The government's goal is 75% of US crop acreage under IPM by
the year 2000. ARE WE THERE YET?
Methods
We took a survey.
The Survey
The Dillman Total Design Method (Dillman 1978; Salant and Dillman 1994)
was used to carry out the survey. Key conceptual elements of the method
include: showing regard for the opinions of the respondent, making the
questionnaire interesting and brief and establishing trust by identifying
with a legitimate or known organization or group. Multiple mailings of
questionnaire and reminders are used to improve response. In order for
growers in each state to be contacted by a person they knew, all cover
letters were printed on letterhead of the state's land grant, and signed
by the state lead person.
The questionnaire was designed to determine adoption of specific pest
and nutrient management practices by northeastern sweet corn growers.
State collaborators participated in several revisions of the instrument.
Mailing lists were obtained from participating state vegetable extension
lists and participants were selected by random number. Our intent was
to sample a sufficiently large subset of the sweet corn grower population
in seven states to provide a 95% confidence interval with a sampling error
within 5%. Sample size was based on the assumption that individuals in
the population are likely to vary in their use of or attitudes to IPM
practices. A total of 1,318 farmers were contacted. Questionnaires were
sent to entire mailing lists of the smaller states. Response rates were
sufficient for our targeted confidence interval (Salant and Dillman 1994).
Analysis
Survey data were compiled to reflect differences in adoption of specific
IPM practices and differences in adoption among states. To measure growers'
adoption of a comprehensive IPM program, we adapted the Massachusetts
Crop Specific IPM Definitions (Hollingsworth et al 1996). In this
system, points are assigned to specific practices, based on their importance
to the IPM system and their difficulty. In Massachusetts IPM certification
projects, 70% of the possible IPM practice points are considered the minimum.
Results & Discussion
Response to the Survey
Survey of sweet corn IPM practices in northeastern
states: response
| |
CT
|
DE
|
DE
|
MD
|
ME
|
NJ
|
PA
|
Total
|
| Questionnaires
sent |
103
|
27
|
146
|
300
|
136
|
203
|
403
|
1318
|
| Valid
surveys returned |
35
|
18
|
72
|
67
|
50
|
129
|
131
|
502
|
| % returned |
34%
|
67%
|
49%
|
22%
|
37%
|
64%
|
33%
|
39%
|
Adoption of IPM
Adoption of specific IPM practices varies among states.
We suspect that variation is strongly influenced by university extension
recommendations. Selection of certain IPM practices, e.g. selection of
blacklight traps or pheromone traps, is clearly determined by local research
and extension activities. Acceptance of certain IPM practices will be
influenced by their costs of implementation. Simple field scouting and
the use of disease resistant cultivars are examples of low cost methods
which are widely implemented. Growers' acceptance of more sophisticated
practices, i.e. pre-sidedress nitrogen testing and use of B.t.,
is likely a reflection of extension efforts in educating growers.
Percent adoption of insect management practices in northeastern
states
| |
CT
|
DE
|
MA
|
MD
|
ME
|
NJ
|
PA
|
Total
|
| Weekly
pest scouting |
85
|
94
|
82
|
72
|
49
|
71
|
62
|
71
|
| Treatment
based on action thresholds |
48
|
71
|
51
|
31
|
28
|
47
|
19
|
38
|
| Plow
under stubble for ECB1 control |
52
|
59
|
70
|
56
|
83
|
60
|
58
|
62
|
| Biological
insecticide (B.t.) |
16
|
6
|
37
|
25
|
23
|
17
|
18
|
22
|
| Field
monitoring for ECB |
71
|
83
|
82
|
58
|
70
|
76
|
47
|
66
|
| Pheromone
Trap for ECB |
14
|
5
|
38
|
9
|
29
|
2
|
5
|
12
|
| Blacklight
for ECB |
3
|
22
|
1
|
13
|
0
|
47
|
2
|
15
|
| Pheromone
trap for CEW2 |
48
|
0
|
39
|
12
|
20
|
1
|
8
|
15
|
| Blacklight
trap for CEW |
0
|
17
|
1
|
15
|
0
|
47
|
2
|
15
|
| Pheromone
trap for FAW3 |
23
|
0
|
33
|
4
|
16
|
2
|
8
|
11
|
| Blacklight
for FAW |
0
|
17
|
1
|
15
|
0
|
41
|
1
|
14
|
| Note:
1ECB,
European Corn Borer 2CEW, Corn Earworm 3FAW,
Fall Armyworm |
Adoption of IPM Practices by Northeast Sweet Corn Growers
Soil and Nutrient Management
| At least
75% of corn acreage rotated annually. |
28%
|
| Fields
evaluated annually with a soil test for nutrient status and pH within
one year. |
36%
|
| A pre-sidedress
nitrate test taken. |
4% |
| Cover
crop is planted to at least 75% of the corn acreage. |
51% |
Pesticide Application
| Pesticide
sprayers calibrated at least once per season. |
76%
|
| All
corn stubble on farm turned under or harrowed before ECB flight. |
62%
|
| A boom
sprayer with drop nozzles used where coverage of the ear zone is desirable. |
24%
|
| Pesticide
coverage of target area and non-target area tested using water- sensitive
spray cards. |
8% |
Insect Management
| Pheromone
or blacklight traps used for corn earworm. |
30%
|
| Pheromone
or blacklight traps used for fall armyworm. |
25%
|
| Pheromone
or blacklight traps used for European corn borer. |
29%
|
| Field
monitoring for European corn borer. |
66%
|
| Insecticide
applications for pest lepidoptera correspond to state university specified
thresholds. |
38%
|
| Biological
insecticide (B.t.) used. |
22% |
Weed Management
| Weeds
monitored annually |
60%
|
| Weeds
controlled by cultivation, with no herbicide applied. |
11%
|
| Herbicide
rates reduced through banding of herbicides and cultivation |
7% |
| Herbicide
use reduced through delayed application of reduced rates of herbicide.
|
16%
|
Disease Management
| Disease
resistant cultivars planted |
84%
|
Measuring adoption of a comprehensive IPM program
The Massachusetts IPM definition provides a comprehensive measure
of IPM adoption, including nutrient, soil, insect, weed and disease management.
Ninety-seven percent of northeastern sweet corn growers do not meet requirements
needed for state IPM certification in Massachusetts. It is significant
that the Massachusetts IPM certification program, Partners with Nature,
certifies 15% of the total sweet corn acreage in Massachusetts, within
the range of IPM adoption estimated by this survey. There higher rate
of IPM adoption by Massachusetts growers in this survey suggests that
IPM certification programs could enhance IPM adoption.
 |
Adoption of 70% (194 points) of the possible IPM practice
points is considered the minimum for adoption of a comprehensive IPM
program.
|
Assessment of sweet corn IPM adoption in northeastern states
| |
CT |
DE |
MA |
MD |
ME |
NJ |
PA |
Total |
| Median
IPM score (number of points) |
115 |
161 |
111 |
87 |
87 |
117 |
72 |
92 |
| Median
IPM score (percent of possible) |
40% |
56% |
39% |
31% |
31% |
41% |
25% |
32% |
| Percent
of growers scoring > 70% of possible score |
3% |
6% |
11% |
2% |
3% |
1% |
0% |
3% |
Conclusion
Our data suggest that we are NOT THERE YET.
Acknowledgments
We thank the following researchers for assistance in developing and conducting
the survey:
Jude
Boucher
University of Connecticut |
Vern
Grubinger
University of Vermont |
Galen
Dively
University of Maryland |
Ruth
Hazzard
University of Massachusetts |
Shelby
Fleischer
Pennsylvania State University |
Donald
Prostak
Rutgers University |
Eleanor
Groden
University of Maine |
Joann
Whalen
University of Delaware |
Selected IPM Articles:
Education
and Certification Report FY 1999
Education and Certification Report FY 2000
Adoption of IPM Systems
Sweet Corn IPM Adoption
IPM in Massachusetts Public
Schools
Partners
with Nature - History
IPM for Bedding Plants - 1996 Survey
Massachusetts
IPM Guidelines
Introduction & Acknowledgements
Apple
Cole Crops
Cranberry
Pepper
Potato
Pumpkin & Squash
Strawberry
Sweetcorn
Field Tomato
Greenhouse Tomato
Highbush Blueberry
Pointsettia
Raspberry
Wine Grape
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