Crop rotation

Crop rotation refers to the cultivation of different crops on a particular piece of land over time. Well-planned rotation schedules benefit soil fertility, aid in pest management, spread labor needs over time and reduce risks caused by market conditions.

The practice of crop rotation, which involves the sequential production of different plant species on the same land, has been in existence for thousands of years. Roman agronomists 2000 years ago thus recommended the practice of alternating legumes and cereals in a rotation, including the use of legumes as green manure.

Reason for crop rotation:
• Creates diversity
• Builds soil organic matter and provide nutrients
• Decreases weed
• Decreases pest and disease problems
• Provides economic value to the farm
• Make use of labor, equipment and knowledge on the farm

Crop rotation helps to create a biodiverse soil which reduces the chance of soil bound organisms to get a pest and reducing the use of pesticides. Crop rotation also helps to minimize the growth of herbs getting a weed that needs to be eradicated and so reducing the use of pesticides.

Crop rotation helps getting a good soil structure (alternatively shallow and deep rooting roots), high organic matter, good water provision, especially in combination with conservation tillage, resulting in a higher yield.

A crop rotation will cycle through cash crops (such as vegetables), cover crops (grasses and cereals) and green manures (often legumes).

It is important to consider crop compatibility when planning a rotation. Some crops may have beneficial interactions and enhance yield, while others may have detrimental effects to subsequent crops. For example, many crops following the cabbage family may have lower yields.

Sweet corn is a good selection to follow the cabbage family because it shows no yield decline. Potatoes are a good crop to follow sweet corn because research has shown sweet corn to be one of the preceding crops that most benefit the yield of potatoes.

Crop rotations must fit with the farm’s production system, equipment, labor, and market demand for the farm’s crops.
Crop rotation

Concept of pollination syndromes

Faegri and van der Pijl 1979 introduced the concept of ‘pollination syndromes’ which can be regarded as stereotypical mutual adaptations of flowering plants and pollinators.

Flowering plants often feature pollination syndromes, sets of traits such as flower color, morphology, scent and nectar production, which appear to fit the morphology and behavior of specific pollinator types.

Although the significance of this concept has been overestimated it it’s a useful way of looking at flowers, because it organizes bodies of facts into recognizable ’picture’.

An idea developed from the concept of pollination syndromes states that pollinators can be clustered into functional groups that behave in similar ways and exert similar selection pressures on the flowers they visit.
Concept of pollination syndromes