Ivydene Gardens Offbeat Glossary: C

Catch Crop

Compost improves the tilth, the water intake, storage, drainage and the aeration of the soil. It helps to control erosion and carries antibiotic and other factors which enhance growth and protect the plants ( See reference 3 ).

Cover crop

Cover crop is a fall seeded crop that covers the ground through the winter and is ploughed down in the spring. They stabilize the soil and prevent erosion; they take up nutrients and prevent them from leaching through the winter months, and they provide a spring green manure.

Crop Rotation.

Cropping sequences are major tools for controlling the soil erosion caused by water and wind. Soil losses not only decrease the depth of the topsoil, they also decrease the organic matter of the topsoil. Rotations that deplete the soil organic matter content decrease soil aggregation, destabilize soil, structure, and hence render soils more susceptible to erosion. Objectives in planning a crop rotation should be:-

1. to select one that will increase, or at least maintain, soil organic matter and Nitrogen content,

2. to make use of different plant families, which make use of different root-space and depth and therefore of the water and nutrient availability from different levels of the soil,

3. and as a major contribution to the prevention of pests and to be very effective in controlling weeds.

The following table shows the differences obtained between the Nitrogen content in the soil after the relevant crop rotation and which crop rotation:-

Crop yields, Soil N Losses, and N Harvested annually for different Rotational Sequences at the Wooster, Ohio, Long-term Crop Rotation Trials.

Each sequence received fertilization that averaged 24 lb manure and 32 lb P/acre on an annual basis. Red clover was harvested for hay and all straw and corn stover was removed.

(1915-1935)

Total soil N balance

Yield of 1st Crop in rotation (1921-1935)

(bu/acre)

(lb/acre)

(% of total)

N harve-sted annually in crops (lb/acre)

27.0

-1000

-65

40

Corn-Wheat

64.0

-210

-9

60

Corn-Soybeans

55.1

-750

-42

55

Corn-Wheat-Red clover

66.3

+360

+12

76

Potatoes*

84.7

-940

-59

16

Potatoes-Wheat

156.0

-170

-7

42

Potatoes-Wheat-Red clover

178.0

+280

+10

52

Soybeans*

14.0

-730

-41

52

Soybeans-Corn

18.9

-750

-42

55

Soybeans-Wheat1

21.5

-150

-6

59

Soybeans-Wheat-Red clover

22.9

+210

+8

63

* Continuously

1 Winter wheat was underseeded in March with sweet clover. Sweet clover was ploughed down in the spring of the following year as a green manure