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D. Some vegetable crop responses to manganese and boron (mostly from Special
 Bulletin 425, Michigan State University Agricultural Experiment Station).


Manganese Requirement


Boron Requirement


Beans
Broccoli
Cabbage
Carrots
Cauliflower
Celery
Chicory & Endive
Cucumbers
Lettuce
Onions
Parsnips
Peas
Potatoes
Radish
Spinach
Sweet Corn
Table Beets
Turnips


High
Medium
Medium
Medium
Medium
Medium
High
Low
High
High
Low
High
High
High
High
Medium
Medium
Medium


Very low
Medium
Medium
Medium
High
High,
Medium
Low
Medium
Very low
Medium
Very low
Low
Medium
Medium
Low
High
Medium


 Crops with a high requirement for manganese will respond to S or 6 sprays
 of 2 Ibs. manganese sulfate applied weekly where the pH is 6.0 and higher; MnO
 dusts are effective but wasteful of material and not as effective as sprays.
 Sprays containing manganese as salts of the ethylene bisdithiocarbamates
 (Maneb, ManZate, M-22, etc.) used as fungicides are effective in supplementary
 foliar manganese nutrition. If used frequent enough, they may supply all of
 the manganese required for the supplementary manganese requirement.

 Crops with a high requirement for boron may respond to 5 or 6 nutritional
 sprays containing 2 lbs. Solubor (20%B) per 100 gallons of water where the
 soil pH is above 6.0. Boron sprays may decrease yield where the soil is 5.5
 and lower.

 Discussion

 From the data presented above, one would expect that if sampling was done
before plowing and the pH was about 6.0 or slightly above, conditions for good
manganese nutrition would be present as the crop matured.

 The large increase in phosphorus availability as the pH was lowered
indicates that available phosphorus might be alarmingly high on presently
highly fertilized high pH soil if the pH were lowered 0.5 pH units or more.

 The data indicate that boron becomes less available as the pH increases
in organic soils within the ranges used here. This is indicated in the second
field celery pH experiment. The increase in calcium uptake by the plant at the
higher pH values may have resulted in a higher boron requirement by the plant
which becomes acute in high boron requiring plants.


Crop