Northwest Crops Project Dennis Pittmann, Dennis Roe and Anitra Gorham

Introduction The Northwest Crops project is in its fourth year. It is managed by Dennis Roe and Dennis Pittmann in cooperation with growers around Whitman County. One of the main focuses of the study has been on managing the heavy residue that results from a direct seeding crop rotation.

Purpose of the Northwest Crops Project To meet the coming challenges in agriculture by developing alternative crops in rotation under no-till. To decrease field burning, erosion, and increase economic stability.

Background The Northwest Crops project was started in 1998 comparing field plots in a three-year rotation of spring barley, chem fallow and winter wheat, and a four-year rotation of spring wheat, winter wheat, corn and a spring broadleaf crop.

Methods All of the crops in rotation were directed seeded. No other implements were used. The corn was planted with a six-row corn planter directly into that residue.

Methods In year one of the field trials each participating grower managed one replicate of the study. Yields, weed density, soil quality changes and insect levels were measured.

Methods The trials were conducted over a range of precipitation zones. Plot widths were approximately 700’ X 30’. Corn production was emphasized and compared with barley.

Four-Year VS Three-Year Rotations The four year rotation versus the three year rotation has several advantages. Corn can be planted into a heavier residue than can cereals. The 30” corn row is planted through the heavy winter wheat stubble compared to the three-year rotation in which wheat is followed by spring barley.

Four-Year VS Three-Year Rotations

The four year rotation decreases erosion by keeping the field covered year round. In the four-year rotation the field is cropped every year. In the three-year rotation the comparatively higher winter wheat yields follow a fallow. Three out of the four years of the study, corn outperformed the barley in yields.

Changing Crops on the Palouse Irrigated corn at Revere, Washington Since the beginning of the Northwest Crops project, neighbors are also comparing corn to their existing crops, as this grower has done with his corn under irrigation.

Expanding the Crops The Northwest Crops project has spurred further studies, such as comparing different varieties of corn. This picture illustrates the Canamaize variety from Canada compared to a Pioneer hybrid.

Expanding the Crops No-till stand-up peas have been grown successfully at Dusty, Washington by growers participating in the Northwest Crops project. The yields are comparable to those in the traditional pea growing areas.

Expanding the Crops Mustard has been grown on some farms as part of the four-year rotation. Canola and mustard have been direct seeded successfully into heavy cereal stubble. There is a growing interest in garbanzos.

Four-Year VS Three-Year Rotations

Residue Working with high residue levels successfully is the key to making a direct seed rotation work. Growers in this project have more success reaching this goal using the four year rotation.

Residue Management The ratio of winter wheat to stubble following fallow is The ratio of winter wheat following crops is 1.10.

Results Corn has a potential as a rotation crop in the intermediate rainfall area. Higher winter wheat yields following corn in rotation compared to winter wheat following barley in the rotation.

Results Erosion has decreased Microbial activity has increased Soil Quality has improved These growers have not practiced field burning on the study.

Further Work In theory the four-year rotation allows more flexible weed management-due to the wider range of chemicals available. This has not always worked in practice, though it is a problem which can be solved.

Conclusion The four year rotation has led to better water infiltration, improved erosion control and a better understanding of high residue management. There is promise for better wheat yields through four year crop rotations.

Questions?