Pear Survey Results

Survey returns: Out of 866 surveys mailed, only 22% were returned. Of those, 74% were from valid pear growers, for which 67% were complete and usable. Of the later group, only 4% were from growers declining to participate for personal reasons. This survey represents approximately 65% of all bearing pear acreage in Washington. Table 17 summarizes the distribution of survey returns across the major growing regions in Washington.

Table 17. Summary of geographic distribution of survey respondents and representative acreage.
Region	% Respondents	# of Acres
Chelan/Manson	5.0%	408.5
Columbia Basin	5.0%	2014.5
Columbia County	0.7%	108.0
Lower Yakima Valley	20.7%	3223.0
Okanogan	12.9%	2562.5
Tri-Cities	1.4%	127.0
Upper Yakima Valley	25.0%	4541.4
Greater Wenatchee Area	29.3%	2783.3

Characterization of farming operations: The percentage of respondents reporting as full-time growers decreased from 84.1% in 1990 to 72.4% in 2000. There was a corresponding increase in respondents reporting as part-time growers, 27.6%, compared with the 1990 survey, 15.9%. This means that more growers are dependant on off-farm income. The average farm size of full-time growers was 136.8 compared to 23.7 for part-time farms. The majority of the respondents, 86.1%, characterized themselves as using conventional pest control practices (primarily using synthetic pesticides), 5.4% as using both conventional and organic means (mixed acres), 3.9% as being transitional to organic, and 4.7% as using only organic farming practices. Table 18 compares data from the 2000 survey with values from the 1990 survey. The most significant change was the increase in the growers involved in organic and transition to organic production. In 1990, only 4.5% of the growers reported being involved in any organic production, while in 2000, 14% reported activity in organic production.

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Growers were asked how many acres of different fruit crops they grew. Table 19 summarizes the results giving the average acreage of each fruit crop and the percentage of growers growing that particular crop for both the 1990 and 2000 survey years. The majority of respondent production acreage was in apple for both survey years, with over 84% of the growers having on average 80 acres. The next largest crop for both years was pear, followed by cherry. None of the 1990 pear survey respondents reported growing grape, where as, about 3% of the year 2000 respondents grew an average of 72 acres.

Growers were also asked to identify the different pear varieties grown in their operations, along with the amount of acreage. The dominant pear variety grown in Washington by survey respondents was Anjou with an average of 14 acres per grower. However, a higher percentage of respondents grew Bartlett. Bosc was the third most popular variety both years.

 

Because pest management decisions may be influenced by the cultivar treated, growers were asked to indicate the percentage of each cultivar present within the reporting block. Table 20 summarizes the breakdown of the total percentage of acreage of each pear variety grown and the amount grown in the reporting blocks.

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Pest management advice: As for Washington apple production, several different sources of information and advice are available to pear growers to help them make pest management decisions. Each potential source of advice was listed in the survey for growers to select and rate their relative usefulness in providing advice for making pest control decisions. The grower responses to the question regarding the importance of different information sources in making pest management decisions is summarized in Table 21. For both survey years, private consultants and chemical company fieldmen were 'very important' sources of information. However, in 2000 the reliance on packinghouse fieldmen dropped from 48.5% as being 'very important' down to 32.6% in 2000. A few less pear growers (77.6%) relied on the Crop Protection Guide then the apple growers (85%, Table 5).

 

The utilization of off-farm sources of information in arriving at pest management decisions varies somewhat in different parts of Washington. Table 22 shows the differences between the percent of respondents from each major fruit growing area rating an information source as 'very important'. Respondents of the 1990 survey came from a slightly different geographic distribution then those of the 2000 survey. This makes a direct comparative breakdown by region between the two years problematic.However,table 22 shows the response data for both survey years for comparable regions. An additional table can be found in the appendix that shows data for all regions for both surveys (Table P1).

The present survey indicates that Yakima Valley growers (LYV and UYV) placed less importance on packinghouse reports than before. All regions still show chemical company fieldmen to be heavily utilized in the decision making process. TheWSU Crop Protection Manual, not available in 1990, is shown to be as very popular choice for information in all growing regions in 2002, as it was for the apple survey respondents.

Pest management activities: Whether conducted by the grower, fieldmen, or private consultants, orchard monitoring was by far the most frequent pest management activity employed with 94% of the respondents indicating its use, and only one individual reportedly never employed monitoring. The next most frequently used technique was pheromone trapping with a portion of the respondents reporting use as 'often' or 'sometimes' at 78%. This amount is up from 68% in 1990. Only about 38% of the growers reported using alternate row spraying as a control practice. This was only a slight decrease from 1990 in which nearly 44% said they either 'often' or 'sometimes' used this practice. The percentage of growers using reduced pesticide rates remained the same at 67%. There was no change in the amount of growers reporting the incorporation of economic thresholds for their management practices with 68% reporting its use during both survey years. In 2000, there was a slight increase in the use of Biological Control practices, with 64% reporting its use compared to 58% in 1990. Also in 2000, two newer methods were incorporated into growerÍs management practices: Degree-day modeling; and integrated mite management. Degree-day modeling uses the accumulated heat units to predict pest out-breaks. Using this method allows growers to time the spray to correspond to the predicted outbreaks. Seventy-seven percent of the respondents reported the use of degree-day models for timing sprays. Integrated mite management was used by 64% of the growers.

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Use of mating disruption: Codling moth mating disruption as a new technique for pest management was not yet available until after the 1990 pear survey was conducted. Therefore, the question in the present survey regarding use of mating disruption by the growers was new, generating baseline data for later comparison. Mating disruption has now been in use commercially in Washington pears since 1991. The growers were asked if they used mating disruption in their reporting block during the 2000 crop season, as well as, to indicate if their overall use of this technique had increased, decreased, or stayed the same since they first began using this technology. Table 24 shows the breakdown of how growers answered. Growers reporting a decrease in acreage treated with mating disruption were asked to indicate the reason. The majority of the growers (75%) reported an increase in the use of mating disruption. Only 17.5% reported a decrease for this practice, with the remaining balance staying the same over time. Of those indicating why the use had decreased, 54% said they had an increase in damage by codling moth and other pests (mealybug, stink bug, lacanobia fruit moth, and leafrollers).

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Reporting block information: The average size of the reporting block was 10.3 acres, the smallest being under one acre and the largest being 52 acres. The average tree density in the reporting blocks for this survey was 169 (a minimum of 56 and a maximum of 389 trees/acre). The density of the 1990 blocks was slightly lower with 145 trees/acre (a range of 34 to 681 trees/acre). The majority of the reporting blocks (over 71%) contained Anjou and Bartlett with Bosc also being prevalent. (Refer to table 20.)

Various horticultural practices can influence pest control activities. Therefore, growers were requested to classify their reporting blocks into categories of tree age, pruning practices, irrigation methods and cover crop management. Table 25 summarizes the responses to these questions.

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Chemical usage in pear orchards

Pesticide use trends: To get a relative rating of how the growers perceive their overall pesticide usage over the past five years (1996-2000), respondents were asked to rate their pesticide use. Fourteen percent reported an increase of pesticide use, 43% decreased, and 37% stayed the same. This compares favorably to the 1990 data where 17% of the growers reportedly increased usage, only 26% decreased usage, and 57% remained the same during the same time interval (1986-1990).

Timing of pesticide applications: A frequent criticism of chemical spray programs is that sprays are made too close to harvest, leaving toxic residues on the fruit. Table 26 summarizes that average last spray date for each class of chemical used in pear orchards, along with the range of when those dates occur. Since pear harvest usually does not begin until mid-August for Bartletts and mid-September for winter pears, none of the chemical sprays from the survey respondents occurred closer than two weeks before these times.

 

Chemical application methods: Survey respondents were asked to indicate how they applied their pesticides, percentage of the block acreage treated, and what volumes were used. Table 27 summarizes those results. Nearly all non-herbicides were applied using an airblast sprayer. Most growers reported 100% acreage treatment with 41.3% using low volume (100-199 gals/acre) applications. Herbicide applications were primarily performed using a boom sprayer.

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Target of pesticide application: Growers were asked to indicate the pest target for each of their chemical applications. They were given a list of targets categorized as insect/mite, or disease. If a specific choice was not given, they were asked to write in the name under the appropriate heading. Table 28 summarizes grower responses to targets of pesticide application, and compares the 2000 data to that of 1990. Pear psylla was still the most frequently cited insect pest with 95% of the growers citing it as a target an average of 4.8 times during 2000. This is a only a slight reduction from 1990 with 98% of the growers citing this pest 4.3 times. Codling moth was also cited to be a problem an average of 2.2 times by 74% of the growers, a slight increase over the 64% of 1990 growers. The worst disease target cited in 2000 was fire blight with 51% of the growers citing 1.7 times during the season, followed by powdery mildew (42% growers citing 1.5 times). It is interesting to note that powdery mildew plagued an equal proportion of growers both survey years. A breakdown of reported targets by region can be found in the appendix (Table P2).

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Chemicals applied: Orchard chemicals were separated into insecticide/miticides, fungides, PGRs and nutrients, and herbicides. Respondents were asked to indicate which chemicals they used for each treatment period and what rate they used. Growers were given a checklist of the most recommended chemicals for each spray period under each chemical type heading. In cases where their chemical was not listed, they were asked to write in the product used under the appropriate heading. This enabled researchers to distinguish what the intended use of each chemical was. This was critical for those chemicals with multiple uses, such as carbaryl that can be used both as an insecticide and a PGR.

Insecticides/miticides: The results for insecticide and miticide usage are shown in table 29. Since 1990, there have been several changes in the availability and allowed usage of insecticides. A comparison of the 1990 and 2000 survey data illustrates these changes. Most notable were the loss of ethylan, parathion, phosphamidon, oxymal, and trithion. Loss of these chemicals, along with stiffer regulations contributed to reduced chemical usage. Since 1990, newer ñsoftî chemicals emerged that have a more target specific activity, or are approved for organic usage. These newer chemicals include: abamectin (Agri-Mek), azadiractin (Neem), fish oil, imidacloprid, kaolin (Surround), and tebufenozide (Confirm). A comparison of regional insecticice/miticide usage is located in the appendix (Table P3).

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Fungicides:  A comparison of fungicide usage during 1990 and 2000 is shown in table 30. As of 2000, several compounds were taken off the market including oxythioquinox (Morestan). However, these compounds were replaced by kresoxim-methyl (Sovran), propiconazole (Orbit), thiram, trifloxystrobin (Flint), and triflumizole (Procure). A comparison of regional fungicide usage is located in the appendix (Table P4).

 

In addition to the loss of some chemicals and gain of others, the most noticeable changes in fungicide usage were the increased use of fenarimol (Rubigan), calcium polysulfide (lime sulfur), and sulfur during the 2000 crop season. However, there was a reduction in the use of copper hydroxide, triadimefon (Bayleton) and ziram. The increase in sulfur and lime sulfur usage may reflect the increase of organic treatments in this crop. Return to top

Plant Growth Regulators (PGRs) and other horticultural chemicals: The primary use of PGRs in pear is for blossom/fruit thinning. In 1990, the only reported PGRs used were NAA and NAD. However, in 2000, growers also reported using a gibberellin (GA14), carbaryl and ethephon.

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Nutrients were difficult to report because most respondents wrote in a product name without indicating the purpose of its use, or only indicated a use without the product name. Since many products are multi-nutrient formulations, the actual intended use cannot be extrapolated. Also, many respondents reported using a leaf-feed without indicating the product, or specific deficiency targeted. The values shown in table 31 are restricted to those nutrients that were fully disclosed. It is important to note that these values for nutrient use cannot be compared to NASS values. NASS only reports phosphorus, potash and nitrogen (generally from manure) applied as soil amendments. Their surveys do not report other forms of nutrient applications. The values reported here for nitrogen reflect non-manure or soil amendment nitrogen. Also, with the use of multi-nutrient formulates for a specific target nutrient deficiency, nitrogen values, and many micro-nutrients, may be under represented.

Herbicides: Herbicides are generally used early in the season and again after harvest to prevent over-wintering of weeds. During the rest of the season, most herbicides are used for spot control. The most common herbicide used both survey years was glyphosate (Roundup). The survey results for herbicide use is summarized in table 32 and compares the 2000 season usage with the 1990 survey results.

The 2000 crop season saw a reduction in the use of nearly all herbicides used during 1990, except oryzalin (Surflan), which more than doubled in 2000. A general reduction for each herbicide may be a reflection of growers using newer compounds that were not available in 1990, such as oxyfluorfen (Goal), fulvic acid (Fulvic 6000) and sulfosate (Touchdown). An overall comparison of chemical usage in pear orchards over the past decade is located in the appendix (Table P5).