grow and to the soil drainage. 

 More cobalt is found in plants 

 growing on poorly drained soils 

 than on well-drained soils. Also, 

 large quantities of organic matter 

 on the surface help to maintain co- 

 balt in forms generally available to 

 plants. 



Many soils have been leached of 

 the mineral material they origi- 

 nally contained. Cobalt can be 

 translocated downward from the 

 surface in the same manner as iron. 

 In many soils of the Southeast and 

 Northeast, less cobalt is found in 

 the surface foot or two than in 

 lower depths. Plants obtain most 

 of their nutrients from the surface 

 foot of soil. Therefore, those 

 plants growing on cobalt-deficient 

 soils are often deficient in cobalt. 



Where does cobalt 

 deficiency occur? 



Soils deficient in cobalt occur in- 

 termittently throughout the North- 

 east from the eastern tip of Wis- 

 consin, across Michigan, in north- 

 eastern New York, and in New 

 Hampshire. Cobalt-deficient areas 

 may also exist in eastern Vermont 

 and southwestern Maine. Some 

 very extensive deficient areas occur 

 in the Coastal Plain of North 

 Carolina and South Carolina. Co- 

 balt-deficient soils are widely dis- 

 tributed over Florida. Ground- 

 water Podzol soils are frequently 

 found in all these areas, and most 

 of the cobalt-deficiency troubles 

 are on these soils. 



Cobalt deficiency has not been 

 reported in the Gulf Coastal Plain. 



Sandy soils occur in this section 

 from Georgia through Texas. 

 However, these soils differ from 

 those of the Atlantic Coastal 

 Plain; no ground- water Podzol 

 soils have been found in this sec- 

 tion. 



Cobalt deficiency is not known 

 to occur on the heavier soils of the 

 South or Middle West. Most 

 Western soils and forage crops 

 grown thereon appear to contain 

 ample cobalt. However, a few 

 areas bordering on cobalt defi- 

 ciency are found in Utah and 

 Nevada. 



How do forages differ 

 in cobalt content? 



Forage crops differ in the 

 amounts of cobalt taken up and 

 stored in their tissues. Legumes 

 take up twofold to tenfold more co- 

 balt than do grasses growing on 

 the same soil. Some grasses, like 

 Kentucky bluegrass, take up more 

 cobalt than other grasses. The up- 

 take of cobalt is important in 

 forage crop management on cobalt- 

 deficient soils. 



The amount of cobalt in forage 

 may range from 0.01 to 0.5 part of 

 cobalt per million parts of dry 

 forage or hay. A good forage will 

 contain 0.1 part per million 

 (p.p.m.) or more of cobalt. A co- 

 balt-deficient forage contains less 

 than 0.05 p.p.m. There may be less 

 than 2 ounces of cobalt in 500 tons 

 of good hay. 



In a cobalt-deficient soil area in 

 New York, hay containing 25 to 50 

 percent of a legume, such as alfalfa, 



