Metals in Crawfish - Aquaculture and the Environment: A Shared Destiny - page 201

Louisiana Crawfish Production Manual
Table 4.1
and land. Additionally, some fixed costs and the costs of a plant crop can be amortized over
two crops rather than just one. Rotational systems can vary based on the type of land, crops
already in production on a farm or past experience of the farmer.
4.3 Rice-crawfish-rice rotation
Rotation of rice and crawfish takes advantage of the seasonality of each crop which allows for
the production and harvest of each crop in one year. Rice is grown and harvested in the
summer months while crawfish grown during the fall, winter and spring in the same field in a
twelve month period. In rice rotation systems the initial stocking takes place 4 to 7 weeks after
the rice is planted. After the rice is harvested in July or August, the residual rice stubble is
fertilized with a nitrogen based fertilizer in order to establish a re-growth crop of rice for
forage. After a fall flooding of the pond, management practices are similar to the
monocropping system. (See Table 4.1) The major disadvantage to this rotational system is that
neither crop can be managed to maximum efficiency. In Louisiana rice yields are maximized
when it is planted in early spring. Draining the ponds and planting rice in early spring
shortens the crawfish harvest season. Delaying the planting of rice will adversely affect rice
yields. Care must be taken in the use of pesticides and herbicides that are helpful to the rice
crop but may be harmful to the crawfish crop. Yields for each crop can vary greatly depending
upon the management emphasis. Generally the crop that is given preferred treatment has
higher yields at the expense of lower yields for the less preferred crop.
4.4 Crawfish-rice-fallow (or rice-crawfish-other plant crop)
The big difference in these rotational strategies is that rice is typically not cultivated in the
same field in consecutive years in order to control rice diseases and weeds. Like rice-
crawfish-rice rotation crawfish culture follows rice cultivation; therefore crawfish