Pulse Production Management after Seeding
• Peas use water down to 3 feet (Wichman, 2005).
• Nodulation begins 2-3 weeks after plant emergence (Jones, 2017).
• Nodules are active 3-4 weeks after plant emergence (Jones, 2017).
• Active nodules are pink to red inside. Inactive nodules are white inside (Jones, 2017).
• Amount of nitrogen fixation depends on species. Green and yellow peas fix more nitrogen than chick pea. Chick peas fix more nitrogen than lentils (Jones, 2017).
• If you notice yellow lower leaves (N deficiency) dig and look for rosy red nodules. Top dress with 40-50 pounds of N per acre up to six weeks after seeding.
• If you notice yellow upper leaves (new leaves) the problem is Sulfur deficiency (Jones, 2017).
• Sulfur soil tests are not reliable because many of our soils have gypsum, which releases sulfur in the lab when combined with warm temperatures (Jones, 2017).
• Both P and K are needed for N fixation (Jones 2017).
• As nitrogen rates increase in the soil, nitrogen benefit from peas decreases.
• Fertility: One year of peas provides about 10# of N/acre. Three years of peas provide about 20 # of N/acre (Jones, 2016).
• Factors affecting nodulation include extreme soil temperatures above 90 degrees, water logged or dry soil, pH less than 5.5 and greater than 8.0 and saline soils (Jones, 2017).
• Irrigation: Give a heavy irrigation put sufficient water down to soil, then cut water off after flowering (Chen, 2016).
• Irrigation: fungicide application at flowering, but applying with irrigation water is not recommended (Chen, 2016).
• Pea Leaf Weevil management: The economic threshold for spraying is reached when 25 percent of the plants have feeding notches on the clam leaf. Foliar sprays can be applied before the 6th node stage (Wanner, 2016).
• Hail Damage will create wounds promoting bacterial blight in peas and lentils (Miller, 2015). Chick peas can recover from hail damage quite well (Miller, 2015) Pulses cannot recover from
See Page 5: Green the effects of blight after late flowering (Kevin McPhee NDSU, 2015).
• Should I spray a fungicide on pulses after a severe hail storm? Hail will increase bacterial blight, which mimic fungal disease symptoms but are not treatable with fungicide. Many of the foliar legume pathogens are splash dispersed, moisture levels are high following rain and temps are favorable. Yield loss is not normally observed on pea and lentil until there is significant loss of leaves and/or stem breakage. (Mary Burrows, 2016)
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