Beans crop rotation

A practice somewhat related to crop rotation is crop diversification or polyculture (36). This approach involves planting selected combinations of crops, like corn and beans. 

Brassicas need firm, moisture-retentive soil they do not thrive in dry conditions. In a crop rotation, this family best follows on from the nitrogen-fixing pea and bean family (see p.242). A green manure crop of winter vetch or clover provides leafy brassicas with all the nitrogen... 

Nakagawa, L.E., L.C. Luchini, M.R. Musumeci, and M. Matallo (1996). Behavior of atrazine in soils of tropical zone Degradation, mobility and uptake of atrazine residues from soils in a crop rotation system (maize/beans). J. Environ. Sci. Health B-Pestic., 31 203-224. 

Principal staple crops rotated at these farms were rice, wheat, and corn other crops included rapeseed, broad beans, peas, soybeans, peanuts, sweet potatoes, and green manures, with a multicropping index between 1.7 and 2. 

In continuous culture, the inoculum progressively builds up in the soil, leading to greater losses each year (e.g., 1% loss in year 1, 19% in year 2, and 22% in year 3 for the cultivar Nahodka ) (Cassells and Walsh, 1995). Control, therefore, is best mediated through rotation with nonhost crops. Since the sclerotia can survive in the soil for up to 7 years, a 3- to 5-year rotation is recommended. Jerusalem artichoke can be rotated with small grains or maize, but not dry edible beans, sunflowers, safflower, mustard, or soybeans — all crops susceptible to sclerotinia wilt. Effective control of weeds, which may act as hosts, and volunteer Jerusalem artichokes is also... 

Soybeans are a common source of protein. They also are hard on the soils and should not be grown in consecutive years on the same field. Alfalfa is a good rotational crop for corn or beans. In some areas of the United States, alfalfa does not grow easily. In those... 

In the vineyard, nitrogen must be fixed into the soil naturally. This is done by planting leguminous crops such as clovers or beans between the vines. These plants have bacteria living on their roots that fix nitrogen from the air. When the plants are dead, they are ploughed in, decay and release nitrogen into the soil. At some wineries, commercial crops such as strawberries are rotated in, which add to the profitability of the vineyard. 

Certain soilborne diseases attack a broad spectrum of crops, and a more complex rotation is necessary to prevent infection. For example, the hactenum Pseudomonas margi-nalis can cause rots of lettuce, beans, cucumbers, and potatoes. If your garden is home to this disease organism, you may have to make it the sole focus of your rotation. Separate the susceptible crops by as much time as possible within your rotation. 

A sound rotation with good weed control in the previous crops particularly of grass weeds and pereimial broad-leaved weeds will reduce the need and cost of weed control in field beans. 

Peas can be a valuable break crop in cereal-based rotations. Peas are N-fixers and the crop debris contains high levels of N. Legumes (peas and beans) should be grown no more than one year in five to prevent the build-up of pests and diseases. 

Leeks (and other allimns) should not be grown more often than one year in fom, and ideally one year in six in the same field. Consideration should also be made of other non-allimn crops in the rotation that are susceptible to bean seed fly, i.e peas, beans, cucmbits. 

Rotations including linseed, lucerne, flax, hops, peas, runner beans or potatoes should be avoided as these may increase levels of Verticillium. Care is also needed in the use of residual herbicides in preceding crops. 

Finally, outside of the risk-reward consideration is the third leg of the stool, which is a little more abstract, and that is mindset. Some growers, albeit relatively few, fall into the early adopted camp and really enjoy or are motivated by the challenge and prospect of pioneering a new crop. Conversely, well-established, tried-and-tested com + bean + com + bean rotation growers would likely be some of the hardest to convince to change, and probably rightly so. 

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