Dry beans are susceptible to salinity, cold soils, spring and fall frosts and excessively wet soils or ponding water. Choose fields that are well-drained, with medium to coarse-textured soils.
Plant into fields without troublesome weeds. Fields with thistles, kochia, buckwheat and lambsquarters are going to be tough to keep clean.
Salinity
High water tables bring soluble salts closer to the soil surface. Followed by dry years, salts are left behind without rainfall to was them down. Salinity reduces root growth, water and nutrient uptake and influence iron deficieny chlorosis symptoms (IDC).
Saline soils are measured using a soil EC test (a dS/m is equivalent to a mmho/cm). Saline soils are those that have an EC value greater than 2.0 mmho/cm. The salinity threshold past which dry beans start to see yield loss is low (0.5 mmho/cm). Dry bean are less tolerant to salinity than soybeans and faba beans. For each increase of 0.5, there is an approximate decrease in yield potential of 20%.
Approximate threshold salinity values for dry beans and yield loss due to salinity:
Dry beans are most commonly grown following cereals, corn or canola.
According to MASC (2010-2015) data, dry bean yield response following wheat and corn is positive (106% and 103%, respectively), and following canola is no different (99%).
Corn residue management can be a challenge. There is an increase white mould (Sclerotinia) risk in dry beans grown on canola, dry bean, soybean and potato stubbles.
Dry bean crop sequence is currently underway at the Applied Pulse and Soybean Lab at the University of Manitoba. At Carman and Portage la Prairie (2018 – 2020) dry beans have been planted into wheat, corn, canola and dry bean stubble.
In this research, dry bean yield was not affected by preceding crop. Dry beans can successfully be established following a range of crops. Some agronomic considerations from this research were:
Planting into canola stubble resulted in slightly greater plant stands than planting into corn stubble (8000 plant/acre difference).
Grassy weed densities were four-fold greater in dry beans following wheat than dry beans following corn.
Root rots were greater on dry beans grown on dry bean stubble.
A Quick Note on Aphanomyces
Dry bean susceptibility to Aphanomyces root rot varies with variety and market class. As a result, dry beans are not considered a break crop like soybeans of faba beans.When dry beans are infected with Aphanomyces, research indicates that few oospores are produced.
The majority of dry bean acres are tilled conventionally, but minimum/reduced till, strip till and no-till are becoming more common. Research indicates that dry bean can successfully be grown in minimum or no-till systems (NDSU).
Residue management was also investigated at the Applied Pulse and Soybean Lab as part of the crop sequence project. Conventional tillage (after harvest and in the spring) versus direct seeded (no-till) conditions were compared. At two out of six site-years, direct seeding increased yield by 10 to 17%, likely due to the added benefits of moisture retention during the dry years of the study (2018-2020). Some agronomic considerations from this research were:
Dry bean plant stands were slightly higher in tilled residue than direct seeded (roughly a 3000 plants/acre difference).
Grassy weed densities were twice as high under tilled conditions versus direct seeded.
The minimum soil temperature for dry bean germination is 12 ⁰C, while soil temperatures greater than 15 ⁰C will result in faster emergence. Dry beans also require sufficient moisture to germinate. With any residue management strategy, there is a trade-off between soil warming and moisture retention. See the example from Aaron Daigh, NDSU below of four residue management strategies tested on-farm in advance of soybean planting.
On-Farm Network Results
Residue management trials in dry beans were initiated in the On-Farm Network in 2020.
In 2020, one trial compared strip till vs. conventional till in canola stubble on very fine sandy loam/clay soils. There was no difference in yield between the two treatments. High winds in early June caused sandblasting throughout the field, though the damage was only great enough to reseed in the conventionally-tilled parts of the field. Comparatively, the strip-tilled parts of the field were relatively undamaged.
