If you suspect zinc deficiency, the 
best way to confirm it is to apply a 
zinc treatment. For a spray test, dis- 
solve a teaspoonful of zinc sulfate in 
a gallon of water and wet the foliage 
of several dozen of the abnormal plants 
with the solution. If zinc—and zinc 
alone—has been deficient, the treated 
plants should resume normal growth, 
and new leaves and stems should show 
no signs of deficiency. 
Spraying is not an effective test 
method for onions or Russet Burbank 
potatoes. Where symptoms of zinc 
deficiency have appeared on either of 
these crops or have appeared in only 
mild form on some other crop, zinc 
treatment for testing purposes may be 
applied to the soil before the next 
spring planting. Mix zinc sulfate in 
the soil at the rate of 2 ounces for 
each 100 square feet, or apply it at 
the same rate as a sidedressing at a 
depth of about 3 inches, 3 inches to 
the side of the row. 
so as 
BN-11893 
Corn stunted and discolored by zinc deficiency. The earliest symptom on corn is 
broad bands of light-colored stripes on the lower leaves. Margins, midribs, and 
tips of the affected leaves stay green. These leaves die prematurely. (Iron defi- 
ciency, also, produces striping on corn leaves, but it affects the upper leaves more 
severely than the lower.) 
