EXERCISE 33 



Fig. 37. Desirable and undesirable types of kernels 



THE BUTT AND TIP KERNELS OF SEED CORN 



Statement. In the development of the corn ear the silks attached to the butt kernels mature first, 

 therefore the butt kernels are the first to form their embryos. The silks attached to the tip kernels 



mature last, and the kernels are the last 

 to form their embryos. The pollen which 

 first ripens is usually produced by barren 

 stalks or by plants which because of 

 their earliness are small. The pollen last 

 produced is from late-maturing stalks, 

 many of which are weak and unproductive. 

 Since the butt and tip kernels are fertilized 

 by pollen from these undesirable plants, such kernels should not be used for seed. Also, the tip 

 kernels do not contain enough stored food for the little plant, nor are they properly shaped to contain 

 a strong germ. 



Object. To compare the relative value of butt, body, and tip kernels for seed. 



Materials. Ears of corn ; a corn planter ; plot of ground, or a box of sand if no plot of ground is 

 available ; a corn grader. 



Directions. 1. Examine kernels from the butt and tip. Note the shape, soundness and size of 

 the grains. 



2. Prop up a corn planter and by turning the wheels test the accuracy of the drop, first using 

 body kernels of corn and then using kernels from the entire ear ; then from the butt ; then from the tip. 



3. Plant in one row of the seed plot or of the box of 

 sand butt kernels of corn. In another row plant body 

 kernels and in the third row plant tip kernels. Give the 

 three rows the same treatment and observe any differences 

 that may occur. Record the number of barren stalks pro- 

 duced in each row; number of ears of corn; amount of 

 corn by weight; number of "suckers," and uniformity of 

 stand. If the exercise is performed indoors, only the early 

 growth can be observed. 



4. Sort one-half peck of shelled corn through a corn 

 grader. Figure the percentage of kernels that are removed. 

 Is the grading of corn in this manner a slow or difficult 

 process? Take the corn that has passed through the grader 

 and sort it by hand, removing any broken, ill-shaped, or 

 undesirable kernels. 



Fig. 38. Good and poor butts and tips 



Questions. What percentage of the kernels are found 

 to be undesirable when run through the grader ? Consider- 

 ing what would have been lost by planting the bad kernels, 

 would it be worth while to hand grade the kernels ? How do uniform kernels help to produce a uni- 

 form stand? Explain how a kernel of seed corn which has been fertilized from a weak or barren 

 stalk is likely to be affected in its power to produce. 



References. Waters, H. J. Essentials of Agriculture, p. 143. Ginn and Company. Hunt, T. F. Cereals 

 in America, pp. 148, 200. Orange Judd Company. Myrick, Herbert. The Book of Corn, pp. 78-79. Orange 

 Judd Company. 



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