WSU Wilke Research and Extension Farm Operation, Production, and Economic Performance for 2024

Authors:
SKU:
TB110E
Published:
March 2026
Combine unloading grain into a portable auger system in a harvested wheat field, with a pickup truck and grain truck positioned alongside.

Table of Contents

The Washington State University Wilke Research and Extension Farm is a 320-acre facility located on the eastern edge of Davenport, Washington. This annual technical bulletin is written primarily for farmers and crop consultants in the intermediate rainfall zone (12 to 17 inches of annual precipitation). It also provides documentation of the operations and production on the farm to assist university faculty with small plot research experiments. Previous technical bulletins can be accessed through the Wheat and Small Grains website.

The Wilke Farm uses a direct-seed cropping system using no­-till fallow, winter wheat, winter canola, spring cereals, and broadleaf crops. The predominant cropping system practiced by farmers in this region is a three-­year rotation that includes summer fallow, winter wheat, and spring cereals, such as wheat and barley. The south side of the farm is divided into seven fields; three fields (2, 5, and 7) are in the predominate three-­year crop rotation, and four fields (1, 3, 4, and 6) are in an intensified four-­year crop rotation. In the three-year rotation, winter canola has been incorporated to generate agronomic and economic crop production data within a rotation. The north side of the farm has been in a continuous cropping system since the inception of the Wilke Farm project in 1998 and has evolved over the past few years. One big change occurred to Field 8, located around the homesite, which was brought into continuous rotation in 2023. Two other changes included changing the names of the “Northwest” and “Northeast” fields to Field 9 and Field 10, respectively.

Soil compaction, soil pH, and wireworm population data are collected each spring from GPS-­recorded locations within each field. Soil samples are also collected from these GPS locations prior to seeding, and fertilizer is applied according to soil sample results and WSU recommendations. Fertilizer rates are expressed as lb/acre in N-P-K-S format. For example, 16-20-0-13 is the application of 16 lb/acre nitrogen, 20 lb/acre P2O2, 0 lb/acre K2O, and 13 lb/acre sulfur.

Operations

All crops in 2023–2024 were seeded with the farm’s John Deere 750 direct­-seed, low disturbance disk drill using a 7.5­-inch row spacing. Deep-banded fertilizer applications are variable rated based on zone requirements and applied in between the rows on a 15-inch spacing. The farm was harvested with its John Deere 9500 combine from July 31 through August 22. Post-harvest weed control was completed with the WEEDit system with an equivalent broadcast rate would have been 34 fl oz/acre Gramoxone SL 3.0, 1 quart/100 gallons NIS, and 2 quarts/100 gallons COC.

3­-Year Crop Rotation

Field 2: Split Between Winter Wheat (64%) and Winter Canola (36%)

  • Variety and Crop: ‘LCS Kraken AX’ soft white winter wheat seeded into fallow.
  • Seed Date and Rate: September 11, 2023, at a seeding rate of 75 lb/acre (23 seeds/ft2).
  • Starter Fertilizer: 6.5 gpa liquid blend (9-15-0.3-1 plus 0.11 lb/ac Zn and 0.08 lb/ac B).
  • Deep Fertilizer: average 60-0-0-5 using a 90% Sol 32 and 10% thio-sul.
    • 28% received 76-0-0-7 or more.
    • 58% received 56-0-0-5 or less.
    • 14% received rates between these values.
  • In-Crop Herbicide: 12 fl oz/acre of Aggressor AX with 1 gallon/100 gallons MSO applied at 20 gpa on April 12, 2024.
  • In-Crop Herbicide: 13.5 fluid oz/acre Huskie, 2 qt/100 gallons Full Load Complete, 32 fluid oz/acre molasses, and 3 gpa Tracite Stand Xtra fertilizer (4-0-0.6-0 plus 0.6 percent calcium, 0.5 percent magnesium, and 3.4 percent chloride) applied at 10 gpa on April 17, 2024.
  • Postharvest Herbicide: 12% of the field was sprayed with the WEEDit, applying 4 fl oz/acre Gramoxone SL 3.0, 0.8 fl oz/acre NIS, and 1.6 fl oz/acre COC in 20 gpa of carrier on September 3, 2024.
  • Variety and Crop: ‘Plurax’ winter canola into fallow.
  • Seed Data and Rate: August 14 through September 1, 2023, at a seeding rate of 4.7 lb/acre (6.7 seed/ft2).
  • Starter Fertilizer: 3.5 gpa liquid blend of 10-34-0 and humic.
  • Deep Fertilizer: 66-0-0-6 using a 90% Sol 32 and 10% thio-sul.
  • In-Crop Herbicide: 12 fl oz/acre Assure II, and 13 fl oz/acre crop oil applied at 10 gpa on April 11, 2024.
  • Insecticide: 3.4 fl oz/acre Lambda-CY, 3 fl oz/acre Preference, 5.5 fl oz/acre Interlock, and 11 fl oz/acre Max-in B applied at 3 gpa. Aerial applied on May 21, 2024, to control cabbage seed pod weevil.
  • Postharvest Herbicide: 63% of the field was sprayed with the WEEDit, applying 20 fl oz/acre Gramoxone SL 3.0, 0.8 fl oz/acre NIS, and 1.6 fl oz/acre COC in 20 gpa of carrier on September 3, 2024.

Field 4: Spring Cereal

  • Variety and Crop: ‘Ryan’ soft white spring wheat.
  • Seed Date and Rate: April 11, 2024, at 86 lb/acre (25 seeds/ft2).
  • Starter Fertilizer: 5.0 gpa liquid blend (7-11-0.4-1 plus 0.04 lb/acre Zn and 0.06 lb/acre B).
  • Deep Fertilizer: Average 44-0-0-5 using a 90% Sol 32 and 10% thio-sul.
    • 20% received 80-0-0-7 or more.
    • 14% received 33-0-0-3 or less.
    • 66% received rates between these values.
  • Preplant Herbicide: 0.3 oz/acre Vesuvius at 10 gpa on March 27, 2024.
  • Preplant Herbicide: 32 fl oz/acre RT3, 1 qt/100 Full Load Complete at 10 gpa on March 29, 2024.
  • In-Crop Herbicide: 18 fl oz/acre MCPA ester, 0.75 oz/acre Quelex, 0.75 qt/100 NIS, and 3 gpa Rally fertilizer (3-0-1.1-0 plus 0.1 Mg, and 1.1 Cl) at 10 gpa on May 31, 2024.
  • Postharvest Herbicide: 6.9% of field was sprayed with the WEEDit, applying 2.2 fl oz/acre Gramoxone SL 3.0, 0.4 fl oz/acre NIS and 0.7 fl oz/acre COC @ 20 gpa on September 3, 2024.

Field 7: No-Till Fallow

  • Variety and Crop: No-till fallow.
  • Herbicide: 12 fl oz/acre Dimetric EXT, 12 fl oz/acre RT3, and 1 qt/100 gallons Full Load Complete was applied at 10 gpa on November 8, 2023.
  • Herbicide: Sprayed with WEEDit in dual mode and 8.9 fl oz/acre RT3 and 0.84 lb/acre AMS applied at 12 gpa on May 9, 2024.
  • Herbicide: 25% of the field was sprayed with the WEEDit, applying 8 fl oz/acre RT3, 1 fl oz/acre Full Load Complete, and 8 fl oz/acre molasses at 12 gpa on June 21, 2024.
  • Herbicide: 47% of the field was sprayed with the WEEDit, applying 15 fl oz/acre RT3, 0.9 fl oz/acre Sharpen,15 fl oz/acre molasses 0.7 lb/acre AMS, and 8.9 fl oz/acre MSO at 15 gpa on July 11, 2024.
  • Herbicide: 9% of the field was sprayed with the WEEDit, applying 3.8 fl oz/acre RT3, 0.13 fl oz/acre Sharpen, 2.8 fl oz/acre molasses 0.13 lb/acre AMS, and 0.4 fl oz/acre Full Load Complete at 15 gpa on July 30, 2024.
  • Herbicide: 4 5% of field was sprayed with the WEEDit, applying 1.7 fl oz/acre Gramoxone SL 3.0, 0.3 fl oz/acre NIS, and 0.7 fl oz/acre COC at 20 gpa on September 3, 2024.

4-­Year Crop Rotation

Field 1: No-Till Fallow

  • Variety and Crop: No-till fallow.
  • Herbicide: 12 fl oz/acre Dimetric EXT, 12 fl oz/acre RT3, and 1 qt/100 gallons Full Load Complete was applied at 10 gpa on November 8, 2023.
  • Herbicide: Sprayed with WEEDit in dual mode and 8.9 fl oz/acre RT3 and 0.84 lb/acre AMS was applied at 12 gpa on May 9, 2024.
  • Herbicide: 36% of the field was sprayed with the WEEDit, applying 11.4 fl oz/acre RT3, 1.4 fl oz/acre Full Load Complete, and 8 fl oz/acre molasses at 12 gpa on June 21, 2024.
  • Herbicide: 44% of the field was sprayed with the WEEDit, applying 14 fl oz/acre RT3, 0.9 fl oz/acre Sharpen, 14 fl oz/acre molasses 0.7 lb/acre AMS, and 8.6 fl oz/acre MSO at 15 gpa on July 12, 2024.
  • Herbicide: 15% of the field was sprayed with the WEEDit, applying 6.5 fl oz/acre RT3, 0.2 fl oz/acre Sharpen, 4.8 fl oz/acre molasses, 0.2 lb/acre AMS, and 0.7 fl oz/acre Full Load Complete at 15 gpa on July 30, 2024.
  • Herbicide: 6% of field was sprayed with the WEEDit, applying 1.8 fl oz/acre Gramoxone SL 3.0, 0.4 fl oz/acre NIS, and 0.7 fl oz/acre COC at 20 gpa on September 3, 2024.

Field 3: Fallow Winter Wheat

  • Variety and Crop: ‘Sockeye CL+’ soft white winter wheat seeded into fallow.
  • Seed Date and Rate: September 13, 2023, at a seeding rate of 88 lb/acre (23 seeds/ft2).
  • Starter Fertilizer: 6.5 gpa liquid blend (9-15-0.3-1 plus 0.11 lb/acre Zn and 0.08 lb/acre B).
  • Deep Fertilizer: Average 77-0-0-7 using a 90% Sol 32 and 10% thio-sul.
    • 28% received 90-0-0-9 or more.
    • 32% received 63-0-0-5 or less.
    • 40% received rates between these values.
  • Top-Dress Fertilizer: 6.7 gpa Sol 32 (24-0-0-0) and 86 fl oz/acre of molasses at 10 gpa on March 22, 2024.
  • In-Crop Herbicide: 4.75 oz/acre Osprey Xtra, 13.5 fl oz/acre Huskie, 2 qt/100 gallons Full Load Complete, 32 fl oz/acre molasses, and 3 gpa Tracite Stand Xtra fertilizer (4-0-0.6-0 plus 0.6 percent calcium, 0.5 percent magnesium, and 3.4 percent chloride), applied at 15 gpa on April 23, 2024.

Field 4: Continuous Winter Wheat

  • Variety and Crop: ‘Sockeye CL+’ soft white winter wheat.
  • Seed Date and Rate: October 4, 2023, at a seeding rate of 88 lb/acre (23 seeds/ft2).
  • Starter Fertilizer: 6.5 gpa liquid blend (9-15-0.3-1 plus 0.11 lb/acre Zn and 0.08 lb/acre B).
  • Deep Fertilizer: average 63-0-0-5 using a 90% Sol 32 and 10% thio-sul.
    • 25% received 66-0-0-6 or more.
    • 13% received 60-0-0-5 or less.
    • 63% received rates between these values.
  • Postplant, Preemergent Herbicide: 3 fl oz/acre Anthem Flex, 16 fl oz/acre RT3, and 1 qt/100 Full Load Complete @ 10 gpa on October 9, 2023.
  • In-Crop Herbicide: 14 fl oz/acre WideARMatch, 32 fl oz/acre molasses, and 3 gpa Tracite Stand Xtra fertilizer (4-0-0.6-0 plus 0.6 Ca, 0.5 Mg, and 3.4 Cl) at 10 gpa on April 23, 2024.
  • In-Crop Herbicide: 5 fl oz/acre Beyond, 10 lb/100 AMS, and 1 qt/100 MSO at 15 gpa on May 3, 2024.

Field 6: Broadleaf

  • Variety and Crop: ‘IdaGold’ yellow mustard.
  • Seed Date and Rate: April 12, 2024. 8 lb/acre and May 3, 2024. 9 lb/acre. Severe frost damage caused replanting.
  • Starter Fertilizer: 5 gpa liquid starter blend (7-11-0.4-1 plus 0.04 Zn and 0.06 B).
  • Deep Fertilizer: average 32-0-0-3 using a 90% Sol 32 and 10% thio-sul.
    • 24% received 40-0-0-3 or more.
    • 18% received 20-0-0-2 or less.
    • 58% received rates between these values.
  • Preplant Herbicide: 32 fl oz/acre RT3, and 1 qt/100 NIS at 10 gpa on March 29, 2024.
  • In-Crop Herbicide: 5-31-24: 5 fl oz/acre Section 2EC, 12 lb/acre AMS, 1gal/100 COC at 12 gpa on May 31, 2024.
    • Section 2EC is no longer registered in Washington State but was labeled at the time of purchase and was applied as specified by the label on the container.
  • Postharvest Herbicide: 34% of field was sprayed with the WEEDit, applying 11 fl oz/acre Gramoxone SL 3.0, 2.2 fl oz/acre NIS, and 4.4 fl oz/acre COC at 20 gpa on September 3, 2024.

Continuous Crop Rotation

Field 8: Continuous Winter Wheat

  • Variety and Crop: ‘Castella’ soft white winter club wheat.
  • Seed Date and Rate: October 4, 2023, at a seeding rate of 77 lb/acre (23 seeds/ft2).
  • Starter Fertilizer: 6.5 gpa liquid blend (9-15-0.3-1 plus 0.11 lb/acre Zn and 0.08 lb/acre B).
  • Deep Fertilizer: Average 66-0-0-6 using a 90% Sol 32 and 10% thio-sul.
    • 15% received 76-0-0-7 or more.
    • 21% received 60-0-0-5 or less.
    • 64% received rates between these values.
  • Postplant, Preemergent Herbicide: 3 fl oz/acre Anthem Flex, 16 fl oz/acre RT3, and 1 qt/100 Full Load Complete at 10 gpa on October 9, 2023.
  • In-Crop Herbicide: 14 fl oz/acre WideARMatch, 32 fl oz/acre molasses, and 3 gpa Tracite Stand Xtra fertilizer (4-0-0.6-0 plus 0.6 Ca, 0.5 Mg, and 3.4 Cl) at 10 gpa on April 23, 2024.

Field 9: Broadleaf

  • Variety and Crop: ‘Invigor L345P’ spring canola.
  • Seed Date and Rate: April 23, 2024, 5 lb/acre (9 seeds/ft2), and May 10, 2024, 5 lb/acre (9 seeds/ft2). Severe frost damage caused replanting.
  • Starter Fertilizer: 5 gpa liquid starter blend (7-11-0.4-1 plus 0.04 Zn and 0.06 B).
  • Deep Fertilizer: Average 32-0-0-3 using a 90% Sol 32 and 10% thio-sul.
    • 24% received 40-0-0-3 or more.
    • 18% received 20-0-0-2 or less.
    • 58% received rates between these values.
  • Preplant Herbicide: 32 fl oz/acre RT3, and 1 qt/100 NIS at 10 gpa on March 29, 2024.
  • In-Crop Herbicide: 5-31-24: 5 fl oz/acre Section 2EC, 12 lb/acre AMS, and 1gal/100 COC at 12 gpa on May 31, 2024.
    • Section 2EC is no longer registered in Washington State but was labeled at the time of purchase, and was applied as specified by the label on the container.
  • Postharvest Herbicide: 81% of field was sprayed with the WEEDit, applying 26 fl oz/acre Gramoxone SL 3.0, 5.2 fl oz/acre NIS, and 10.4 fl oz/acre COC at 20 gpa on September 4, 2024.

Field 10: Spring Cereal

  • Variety and Crop: ‘BG2020’ food grade spring barley.
  • Seed Date and Rate: April 18, 2024, at 63 lb/acre.
  • Starter Fertlizer: 5.0 gpa liquid blend (7-11-0.4-1 plus 0.04 lb/acre Zn and 0.06 lb/acre B).
  • Deep Fertilizer: Average 45-0-0-5 using a 90% Sol 32 and 10% thio-sul.
    • 32% received 60-0-0-5 or more.
    • 28% received 33-0-0-3 or less.
    • 40% received rates between these values.
  • Preplant Herbicide: 32 fl oz/acre RT3 and 1 qt/100 Full Load Complete at10 gpa on March 29, 2024.
  • In-Crop Herbicide: 15 fl oz Axial Bold, 0.8 oz/acre Affinity Broadspec, 0.75 qt/100 NIS, and 3 gpa Rally fertilizer (3-0-1.1-0 plus 0.1 Mg and 1.1 Cl) at 10 gpa on May 31, 2024.
  • Postharvest Herbicide: 27% of field was sprayed with the WEEDit, applying 8.6 fl oz/acre Gramoxone SL 3.0, 1.7 fl oz/acre NIS, and 3.4 fl oz/acre COC at 20 gpa on September 4, 2024.

Soil Compaction

Soil compaction data were collected with a Spectrum FieldScout SC900 Soil Compaction Meter. Data were collected within each field in the spring of the year prior to seeding to determine changes in compaction over time. Compaction levels are monitored within each field and within a given crop rotation, which assists in potential management decisions in the future. Figure 1 shows soil compaction data collected in the spring of the year from six fields at the WSU Wilke Research and Extension Farm in 2024.

Line graph showing soil compaction in pounds per square inch (psi) by depth from 0 to 18 inches for six fields (Fields 1, 5, 6, 7, 9, and 10). Compaction generally increases from the soil surface to a peak at approximately 6–8 inches, then decreases with greater depth. Field 10 shows the lowest overall compaction, averaging 157 psi across 18 inches, while Field 1 shows the highest average compaction at 189 psi. Fields 5, 6, 7, and 9 have intermediate average compaction values of 168, 179, 187, and 178 psi, respectively. Across all fields, the highest compaction values are consistently observed at mid-depth (6–8 inches).
Figure 1. In this line graph showing compaction (psi) measurements from zero inches to a depth of 18 inches, Field 10 had the least amount of compaction with an average of 157 psi per 18 inches, and Field 1 had the greatest average soil compaction with 189 psi per 18 inches. For Fields 5, 6, 7, and 9, compaction averaged 168, 179, 187, and 178 psi per 18 inches, respectively. Maximum compaction levels were typically observed at six- to eight-inch depths.

Soil Samples

Soil samples were collected prior to seeding each crop from three production zones in each field. Data were used to help determine yield potential and nutrient requirements for the crops within these zones. Soil sample data presented on planted crops is an average of the three production zones in each field (Tables 1, 2, 5, 6, 7, 8, 9, and 10). No-till fallow fields are sampled in the same five GPS-marked locations at the same time as those fields being spring-cropped (Tables 3 and 4). The sum of tested nitrogen to a depth of four feet is determined by adding the estimated soil organic matter (SOM) released nitrogen, ammonium nitrogen in the first foot, and the four-foot total of nitrate nitrogen. For example, in Table 11, SOM is 46 lb N/acre, ammonium N is 10 lb N/acre and nitrate N is 144 lb N/acre for a sum of 200 lb N/acre in four feet.

3-­Year Crop Rotation

Table 1. Fallow–winter wheat/canola, Field 2. In the top foot, soil pH is 5.3, SOM is 2.3% and will release an estimated 46 lb N/acre, ammonium N is 10 lb N/acre, phosphorus is 20 ppm, and potassium is 609 ppm. The sum of tested nitrogen to a depth of four feet is 200 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
18791.8
21872.0
31381.4
426-1.3
Total144236.5
Table 2. Spring wheat, Field 5. In the top foot, soil pH is 5.9, SOM is 3.2% and will release an estimated 65 lb N/acre, ammonium N is 14 lb N/acre, phosphorus is 17 ppm, and potassium is 581 ppm. The sum of tested nitrogen to a depth of four feet is 137 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
11472.9
221212.9
31252.2
411-1.9
Total57339.8
Table 3. No-till fallow, Field 7. In the top foot, soil pH is 5.7, SOM is 2.7% and will release an estimated 55 lb N/acre, ammonium N is 7 lb N/acre, phosphorus is 17 ppm, and potassium is 581 ppm. The sum of tested nitrogen to a depth of four feet is 108 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
11132.9
21262.8
31082.3
413-2.3
Total461810.2

4-­Year Crop Rotation

Table 4. No-till fallow, Field 1. In the top foot, soil pH is 5.3, SOM is 2.9% and will release an estimated 59 lb N/acre, ammonium N is 6 lb N/acre, phosphorus is 20 ppm, and potassium is 671 ppm. The sum of tested nitrogen to a depth of four feet is 145 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
11573.0
21362.2
32142.8
431-2.3
Total801710.2
Table 5. Fallow–winter wheat, Field 3. In the top foot, soil pH is 5.6, SOM is 2.2% and will release an estimated 44 lb N/acre, ammonium N is 8 lb N/acre, phosphorus is 15 ppm, and potassium is 570 ppm. The sum of tested nitrogen to a depth of four feet is 170 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
157112.0
22051.9
32161.4
421-1.3
Total118236.7
Table 6. Continuous winter wheat, Field 4. In the top foot, soil pH is 5.8, SOM is 2.0% and will release an estimated 38 lb N/acre, ammonium N is 11 lb N/acre, phosphorus is 21 ppm, and potassium is 437 ppm. The sum of tested nitrogen to a depth of four feet is 99 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
113230.9
26370.8
3650.7
426-0.8
Total50653.3
Table 7. Yellow mustard, Field 6. In the top foot, soil pH is 5.6, SOM is 3.2% and will release an estimated 63 lb N/acre, ammonium N is 24 lb N/acre, phosphorus is 39 ppm, and potassium is 654 ppm. The sum of tested nitrogen to a depth of four feet is 165 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
117182.7
219142.5
31051.9
433-1.6
Total79378.7

Continuous Rotation

Table 8. Continuous winter wheat, Field 8. In the top foot, soil pH is 5.7, SOM is 1.5% and will release an estimated 30 lb N/acre, ammonium N is 15 lb N/acre, phosphorus is 26 ppm, and potassium is 392 ppm. The sum of tested nitrogen to a depth of four feet is 88 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
117111.1
2841.4
35420.8
413-1.0
Total43574.4
Table 9. Spring canola, Field 9. In the top foot, soil pH is 5.4, SOM is 3.2% and will release an estimated 64 lb N/acre, ammonium N is 16 lb N/acre, phosphorus is 20 ppm, and potassium is 572 ppm. The sum of tested nitrogen to a depth of four feet is 181 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
117111.1
2841.4
35420.8
413-1.0
Total43574.4
Table 10. Continuous winter wheat, Field 10. In the top foot, soil pH is 6.0, SOM is 2.7% and will release an estimated 54 lb N/acre, ammonium N is 12 lb N/acre, phosphorus is 14 ppm, and potassium is 404 ppm. The sum of tested nitrogen to a depth of four feet is 102 lb/acre.
Soil Depth (ft)Nitrate-N (lb/acre)Sulfate-S (mg/kg)Soil Water (in)
111142.6
28102.4
37111.6
410-1.5
Total37358.2

Soil pH and KCl Extractable Aluminum (Al)

Soil pH and exchangeable Al soil samples are collected prior to seeding in fields planted to spring crop and no-till fallow (NTF). Soil samples are collected from the same five GPS locations where soil compaction is collected. Samples are collected at a depth of 0–3, 3–6, and 6–12 inches. Aluminum toxicity traditionally begins to occur when soil pH levels are less than 5.0 and KCl extractable Al measurements are greater than 25 ppm. At a depth of 0–3 inches, soil pH levels are above 5.0, and KCl Al ranged from 1.1 to 13.2 ppm (Table 11). At a depth of 3–6 inches, soil pH levels ranged from 4.9 to 5.3, and KCl Al ranged from 3.7 ppm in Field 10 to 25.8 ppm in Field 1 (Table 12). At a depth of 6–12 inches, pH ranged from 6.1 to 6.3, and KCl Al ranged from 0.4 to 2.7 ppm (Table 13).

Table 11. Soil pH and KCl extractable aluminum at a soil depth of 0–3 inches in six fields at the WSU Wilke Research and Extension Farm in the spring of 2024.
Soil IndicatorField 1 (NTF)Field 5 (SWSW)Field 6 (mustard)Field 7 (NTF)Field 9 (canola)Field 10 (barley)
pH5.35.25.25.25.25.4
KCl Al (ppm)3.24.913.210.44.11.1
Table 12. Soil pH and KCl extractable aluminum at a soil depth of 3–6 inches in six fields at the WSU Wilke Research and Extension Farm in the spring of 2024.
Soil IndicatorField 1 (NTF)Field 5 (SWSW)Field 6 (mustard)Field 7 (NTF)Field 9 (canola)Field 10 (barley)
pH4.95.15.15.25.05.3
KCl Al (ppm)25.824.221.615.816.13.7
Table 13. Soil pH and KCl extractable aluminum at a soil depth of 6–12 inches in six fields at the WSU Wilke Research and Extension Farm in the spring of 2024.
Soil IndicatorField 1 (NTF)Field 5 (SWSW)Field 6 (mustard)Field 7 (NTF)Field 9 (canola)Field 10 (barley)
pH6.26.36.26.26.26.1
KCl Al (ppm)2.70.70.81.20.70.4

Production and Economic Performance

Nitrogen uptake efficiency (NUE) was at or above 50 percent for all four soft white winter wheat (SWWW) fields (Table 14). For fields at or above 50 percent, this implies the nitrogen fertilizer program was adequate, and an average amount of nitrogen should be available in the soil for next year’s production. Field 5 was soft white spring wheat (SWSW) and had NUE of 44 percent, which implies the crop was overfertilized or fertilizer timing could be adjusted. Above-average fertilizer should be available for next year’s production in this field. Soft white wheat traditionally requires 2.7 lb N/bu, and in 2024, across the farm, it ranged from 2.7 to 3.6 lb N/bu.

Table 14. Nitrogen use efficiency by field in 2024.
NUE ComponentsField 2 (SWWW)Field 3 (SWWW)Field 4 (SWWW)Field 5 (SWSW)Field 8 (SWWW)
Soil Test Nitrogen*180132959785
Applied Nitrogen73114795478
Total Nitrogen253246174151163
Grain Yield85.870.654.342.256.2
Grain Protein9.8%9.9%10.8%10.5%9.9%
lb N/bu3.02.73.23.62.9
Nitrogen Uptake Efficiency50%55%51%44%51%

*Soil test nitrogen is calculated by inputting soil test results into the WSU Dryland Wheat Nitrogen Fertilizer Calculator.

Freezing temperatures on May 1, May 2, and May 7 severely damaged spring canola and mustard seedlings resulting in reseeding. Freezing nights were also recorded on May 18 and June 16, which limited yields of all crops. The WSU Wilke Farm grain marketing plan, which begins once the crop has emerged, uses forward contracts and postharvest selling. All grain is marketed by November 15. The average marketing window for winter wheat is about 13 months, and 7 months for spring crops. Forward contract values do not exceed the crop revenue insurance coverage value. The potential for a forward contract is evaluated monthly and is based on a targeted rate of return on investment based on estimated expenses. In 2024, 48% of the SWWW crop was forward contracted, and no canola was forward contracted. Both mustard and barley were raised under production contracts. Market grades for each crop are provided as these also impact the final market price.

Average input costs per year at the WSU Wilke Farm were up 6% over the three-year average (2021–23). However, economic returns over input costs were down 49%. Tables 15–20 summarize the rotation, production, and economic performance of the three-­year rotation, four­-year rotation, and continuous cropping system at the Wilke Farm in 2024.

Return above input costs per rotation is calculated by multiplying each field’s return over costs by the acre to find the total return over cost and dividing it by the total acres in the rotation. The three-year crop rotation returns above input costs averaged $91.89/acre, 39% less than the three-year average. The four-year crop rotation returns above input costs averaged $111.37/acre, 42% less than the previous three-year average. The continuous cropping system returns above input costs averaged $66.43/acre, 65% less than the previous three-year average. The WSU Wilke Farm is enrolled in the USDA Farm Program and purchases crop insurance each year. Revenue associated with the farm program is not included, but revenue and costs associated with crop insurance are included in the field summaries.

Table 15. Three-year cropping rotation sequence at the Wilke Farm from 2020 to 2025.
YearField 2Field 5Field 7
2020No-till FallowWinter Wheat/Canola (76 bu/acre; 2,080 lb/acre)Spring Wheat (55.5 bu/acre)
2021Winter Wheat (55.5 bu/acre)Spring Wheat (24.3 bu/acre)No-till Fallow
2022DNS Wheat (38.8 bu/acre)No-till FallowWinter Wheat (77.5 bu/acre)
2023No-till FallowWinter Wheat/Canola (72.0 bu/acre; 1,053 lb/acre)Spring Wheat (38.7 bu/acre)
2024Winter Wheat/Canola (85.8 bu/acre; 1,935 lb/acre)Spring Wheat (42.2 bu/acre)No-till Fallow
2025Spring CerealNo-till FallowWinter Wheat/Canola
Table 16. Three-year crop rotation production at the Wilke Farm, 2024. The three-year rotation economic return over input costs is $91.89/acre. This does not include fixed costs associated with the farm.
-Field 2Field 2Field 5Field 7
Acreage16.19.02635.1
Variety/Crop‘LCS Kraken AX’ SWWW‘Plurax’ Winter Canola‘Ryan’ SWSWNo-till fallow
Yield85.8 bu/acre1,935 lb/acre42.2 bu/acre-
Mkt Grade#1 SWH, 60.0, 0.3% dockage#1 non-GMO canola, 2.4% dockage#2 SWH, 59.5, 0.7% dockage-
Mkt Price$5.30/bu$0.1935/lb$5.25/acre-
Crop Sales Income$454.74/acre$374.42/acre$221.55/acre-
Insurance Income$47.52/acre$20.11/acre$32.62/acre-
Gross Economic Returns$502.26/acre$394.53/acre$254.17/acre-
Seed Cost$29.25/acre$68.44/acre$28.17/acre-
Fertilizer Cost$86.32/acre$74.83/acre$66.22/acre-
Herbicide Cost$60.05/acre$24.87/acre$24.09/acre$37.64/acre
Insecticide Cost-$16.18/acre--
Insurance Cost$28.51/acre$21.44/acre$30.18/acre-
Total Costs$204.13/acre$205.76/acre$148.66/acre$37.64/acre
Return over Costs$298.13/acre$188.77/acre$105.51/acre-$37.64/acre
Table 17. Four-year cropping rotation sequence at the Wilke Farm from 2020 to 2025.
YearField 1Field 3Field 4Field 6
2020No-till FallowWinter Wheat (99.2 bu/acre)Winter Barley (1.82 ton/acre)Spring Canola (1,755 lb/acre)
2021Winter Wheat (60.2 bu/acre)Spring Canola (not harvested, frost)No-till FallowSpring Wheat (21.4 bu/acre)
2022Spring Canola (1,290 lb/acre)Winter Wheat (67.9 bu/acre)Winter Wheat (90.4 bu/acre)No-till Fallow
2023Winter Wheat (37.4 bu/acre)No-till FallowSpring Canola (1,600 lb/acre)Winter Wheat (73.3 bu/acre)
2024No-till FallowWinter Wheat (90.6 bu/acre)Winter Wheat (54.3 bu/acre)Yellow Mustard (399 lb/acre)
2025Winter WheatBroadleafNo-till FallowWinter Wheat
Table 18. Four-year crop rotation production at the Wilke Farm, 2024. The four-year rotation economic return over input costs is $111.37/acre. This does not include fixed costs associated with the farm.
-Field 1Field 3Field 4Field 6
Acreage18.127.225.729.5
CropNo-till Fallow‘Sockeye CL+’ SWWW‘Sockeye CL+’ SWWW‘IdaGold’ Yellow Mustard
Yield-90.6 bu/acre54.3 bu/acre399 lb/acre
Mkt Grade-#2 SWH, 59.2, 0.3% dockage#2 SWH, 58.3, 0.5% dockage#1 SWH, 61.8, 0.2% dockage
Mkt Price-$5.26/bu$5.22/bu$0.37/lb
Crop Sales Income-$476.56/acre$283.45/acre$147.63/acre
Insurance Income-$47.52/acre$14.74/acre$24.75/acre
Gross Economic Return-$524.08/acre$298.19/acre$172.38/acre
Seed Cost-$29.41/acre$29.41/acre$59.65/acre
Fertilizer Cost-$117.38/acre$88.00/acre$47.27/acre
Herbicides Cost$39.65/acre$39.71/acre$53.62/acre$23.59/acre
Insurance Cost-$28.51/acre$28.51/acre$9.06/acre
Total Costs$39.65/acre$215.01/acre$199.54/acre$139.57/acre
Return over Costs-$39.65/acre$309.07/acre$98.65/acre$32.81/acre
Table 19. Continuous crop rotation sequence at the Wilke Farm from 2020 to 2025.
YearField 8Field 9Field 10
2020Spring Wheat (59.5 bu/acre)Spring Wheat (49.6 bu/acre)Spring Wheat (49.6 bu/acre)
2021No-till FallowSpring Canola (705 lb/acre)Spring Wheat (20.3 bu/acre)
2022Winter Wheat (83.9 bu/acre)Winter Wheat (51.7 bu/acre)Spring Canola (1,336 lb/acre)
2023Yellow Mustard (755 lb/acre)Spring Barley (1.43 ton/acre)Winter Wheat (45.2 bu/acre)
2024Winter Wheat (56.2 bu/acre)Canola (806 lb/acre)Spring Barley (0.77 ton/acre)
2025Spring CerealWinter WheatBroadleaf
Table 20. Continuous crop rotation production at the Wilke Farm, 2024. The continuous crop rotation economic return over input costs is $66.43/acre. This does not include fixed costs associated with the farm.
-Field 8Field 9Field 10
Acreage26.931.432.5
Crop‘Castella Club’ Winter Wheat‘Invigor L345P’ Spring Canola‘BG2020’ Spring Barley
Yield56.2 bu/acre806 lb/acre0.77 ton/acre
Mkt Grade#1 WHC, 59.5, 1.0% dockage#1 GMO, 2.3% dockageNon-standard, 47.0, 0.89% dockage
Mkt Price$5.24/bu$0.186/lb$284/ton
Crop Sales Income$294.49/acre$149.92/acre$218.68/acre
Insurance Income$14.74/acre$65.55/acre$39.66/acre
Gross Economic Return$309.23/acre$215.47/acre$258.34/acre
Seed Cost$24.70/acre$140.00/acre$25.72/acre
Fertilizer Cost$90.55/acre$42.54/acre$63.98/acre
Herbicide Cost$34.37/acre$50.52/acre$35.57/acre
Insurance Cost$28.51/acre$24.28/acre$15.54/acre
Total Costs$178.13/acre$257.34/acre$140.81/acre
Return over Costs$131.10/acre-$41.87/acre$117.53/acre

Weather

Weather data in 2024 (Table 21) and 2023 (Table 22) are provided. Overall, May was colder than average with 18% less growing degree days (GDD) than the previous ten-year average.

Table 21. Weather data for Davenport, Washington in the 2024 crop year (September 1, 2023, to August 31, 2024). Temperatures are recorded in degrees Fahrenheit (°F).
MonthHigh TemperatureLow TemperatureMean TemperatureGrowing Degree Days†Rainfall (in.)Rain Days
971.245.858.98050.726
1157.235.745.75040.579
1139.627.533.11221.5610
123628.132.2452.8814
130.320.425.4551.5714
239.528.633.8971.4915
349.528.539.02360.597
456.033.244.83780.845
564.438.852.76080.934
672.544.059.77880.726
788.856.074.11,2530.000
882.453.268.81,1100.112
Total---6,00111.0984

†Growing degree calculated using 32°F as the base temperature.

Table 22. Weather data for Davenport, Washington, in the 2023 crop year (September 1, 2022, to August 31, 2023). Temperatures are recorded in degrees Fahrenheit (°F).
MonthHigh TemperatureLow TemperatureMean TemperatureGrowing Degree Days†Rainfall (in.)Rain Days
976.248.262.29050.404
1165.740.552.36540.374
1132.818.525.7200.799
1224.514.020.472.907
132.923.728.7261.5612
237.321.328.6450.364
343.826.434.61220.6710
454.531.943.53361.7411
572.547.560.48680.899
676.049.163.89160.665
785.854.571.61,1810.272
883.155.169.81,1510.487
Total---6,23211.0984

†Growing degree calculated using 32°F as the base temperature.

Summary

A summary of WSU Wilke Research and Extension Farm economic returns over input costs using three­-year averages is shown in Figure 2.

Bar chart showing dollars per acre for three systems—3-Year (green), 4-Year (red), and Continuous (blue)—across years 2019–21, 2020–22, 2021–2023, 2022–2024, and a Mean category. In every year, the 4-Year system has the highest values, Continuous is second, and 3-Year is lowest. Values generally increase from 2019–21 to 2020–22 and remain relatively high through 2022–2024. The Mean bars follow the same pattern, with statistical letters indicating 4-Year and Continuous are not significantly different (both labeled “A”), while 3-Year is lower (“B”).
Figure 2. In this bar graph, it shows the three-year average economic return over input costs of three-year, four-year, and continuous cropping systems at the WSU Wilke Research and Extension Farm. Costs do not include fixed costs associated with the farm. Means within columns assigned different case letters are significantly different (p < 0.10). Over the last three years (2022 to 2024), the three-­year rotation, four­-year rotation, and continuous cropping rotation have averaged returns above input costs of $144, $186, and $158 per acre, respectively. Over the last six years, the continuous rotation and four-­year rotation have averaged returns above input costs of $169 and $175 per acre, respectively, and are not significantly different. The three-year rotation has averaged $143/acre return above costs during this period and is significantly less than both the continuous rotation and the four-year rotation.

The chart compares economic returns ($/acre) for three cropping systems over four time periods plus an overall mean. The y-axis ranges from 0 to 250 $/acre.

  • 2019–21: 3-Year ≈125, 4-Year ≈135, Continuous ≈150
  • 2020–22: 3-Year ≈150, 4-Year ≈190, Continuous ≈180
  • 2021–2023: 3-Year ≈150, 4-Year ≈190, Continuous ≈190
  • 2022–2024: 3-Year ≈140–145, 4-Year ≈185, Continuous ≈160
  • Mean: 3-Year ≈140 (labeled B), 4-Year ≈175 (A), Continuous ≈170 (A)

Across all periods, the 4-Year system consistently produces the highest returns, followed by Continuous, with 3-Year lowest. The mean comparison indicates that 4-Year and Continuous are statistically similar and both outperform the 3-Year system.

WSU Wilke Research Plots

Research and outreach are a large component of the farm. In 2023–24, there were 13.75 acres of Farm Service Agency (FSA) certified research plots in the fall and an additional 2.0 acres certified in the spring. These are mostly small research plots established and harvested with plot equipment. Large-scale research plots are not certified as research, because they are harvested with the commercial combine and grain is taken to the warehouse. Below is a list of the projects being conducted on the farm.

Small Plots

  • University of Idaho. “Spring Canola Variety Plots.” This project helps companies bring the best canola genetics to market and helps farmers with selecting the best genetics.
  • University of Idaho. “Winter Canola Variety Plots.” This project helps companies bring the best canola genetics to market and helps farmers with selecting the best genetics.
  • Arron Carter, WSU. “Soft White Wheat Breeding Plots.” These are the advanced generation selections for the intermediate rainfall zone.
  • Aaron Esser, WSU. “Spring Cereal Seed Treatment Studies.” These studies look at biological and fungicidal seed-applied products to reduce disease and improve yield.
  • Aaron Esser, WSU. “Mycorrhiza Application in Winter Wheat.” This study examines commercially available mycorrhiza products applied to winter wheat following both winter spring canola.
  • Aaron Esser, WSU. “Pivot Bio Evaluation in Winter Wheat on Fallow, Continuous Winter Wheat, and Spring Wheat.”
  • Ian Burke, WSU. “Herbicide Evaluation.” This project is examining many different compounds for weed control in predominate wheat production systems.
  • Michael Pumphrey, WSU. “Liming and Aluminum Tolerant Varieties of Wheat Interaction.”
  • Garett Heineck, USDA/ARS. “Kernza Perennial Cropping System.”
  • Don Llewellyn, WSU Extension. “Forage Evaluation for Dryland Agriculture.”
  • Haly Neely, Shikha Singh, Don Lewellen, and Aaron Esser. “Cover Crop Mix Feasibility.”
  • Shikha Singh, WSU. “Spring Peola Feasibility.”
  • Clark Neely, WSU. “Spring Legume Variety Trial.”

Large Plots

  • Aaron Esser, WSU. “Benefits of Spring Fungicide and Pi-Dust Application in Winter Wheat Production.”
  • Jesse Ford, WSU. “Spring Canola Variety Plots.” This project evaluated six spring canola varieties and is designed to help farmers select the best genetics for their situation.
  • Ian Burke, WSU. “Compost Application and Winter Pea Production Feasibility in the Intermediate Cropping System.” This study was initiated in the fall of 2016.
  • Aaron Esser, WSU. “Calcium Carbonate Application to Improve Soil pH and Improve Profitability.” This study was initiated in the fall of 2016.
  • Aaron Esser, WSU. “Value of Incorporating Spring Canola and Chickpea into Cereal Grain Cropping Systems.” This study was initiated in the spring of 2014.
  • Aaron Esser, WSU. “Cover Crop Feasibility as a Replacement for Summer Fallow Systems.”
  • Haly Neely, Shikha Singh, Don Lewellen, and Aaron Esser. “Long-Term ‘Cow Chow’ Cover Crop Feasibility.”

Special Thanks

Yellow field of spring canola.
BASF donated the spring canola seed for the WSU Wilke Research and Extension Farm in 2024.
Picture showing the weather station at the WSU Wilke Research and Extension Farm.
AgWeatherNet station at the WSU Wilke Research and Extension Farm.

AGWEATHERNET STATION located at the Wilke Research and Extension Farm.

You can access Wilke weather data at AgWeatherNet | Washington State University (wsu.edu).

AgWeatherNet link on the widget takes you to a map of weather stations throughout the state.


For additional information, please contact Aaron Esser, aarons@wsu.edu, 509-660-0566.

By,
Aaron Esser, Wilke Farm Management Committee Chair, Washington State University
Derek Appel, Wilke Farm Manager, Washington State University

WSU Peer Reviewed logo.

TB110E

Washington State University Extension Cougar Logo.

Copyright © Washington State University

WSU Extension publications contain material written and produced for public distribution. Alternative text descriptions for select complex images were generated using ChatGPT (OpenAI, GPT-5.2), then reviewed and adapted to ensure compliance with Web Content Accessibility Guidelines (WCAG) 2.1, Level AA accessibility standards.

Issued by Washington State University Extension and the US Department of Agriculture in furtherance of the Acts of May 8 and June 30, 1914. Extension programs and policies are consistent with federal and state laws and regulations on nondiscrimination regarding race, sex, religion, age, color, creed, and national or ethnic origin; physical, mental, or sensory disability; marital status or sexual orientation; and status as a Vietnam-era or disabled veteran. Evidence of noncompliance may be reported through your local WSU Extension office. Trade names have been used to simplify information; no endorsement is intended.