644 PRACTICAL PROBLEMS 



Plot or row in the nursery system. Shall the individuals of a 

 single selection be planted together in rectangles or grown in 

 separate rows ? Each system has its advocates, and the matter 

 is to be decided first of all by convenience in cultivation and 

 harvesting, and second by convenience in keeping records. The 

 two systems are well illustrated by the methods employed at 

 the two experiment stations of Minnesota and Illinois. 



The plot system. This system is best described by its use at 

 the Minnesota station, where it has been fully elaborated and is 

 constantly employed for all breeding work. 1 Under this system 

 as there employed the procedure is substantially as follows, 

 taking wheat as an illustration. When a new variety is received 

 or a promising plant is selected its history is recorded on a 

 record sheet 5^ x 8^ inches and punched at the end for filing. 

 It is given a class name and a number of its own (" Nursery 

 Stock No. - "), and if it sprang from a numbered stock, that 

 number is also recorded as " Parent Stock No. ." This sheet 

 is known as the " Introductory Sheet," and is reproduced here 

 on a reduced scale. 



Form 61 



SELECTED STOCK INTRODUCTORY SHEET 



Nursery 



S::cx N:. 



M/HPAT Class Name of Minn. No. of 



WHtAl stock Parent Stock.. 



Date- 

 Origin and History of Parent Stock 



The seed is then planted by itself in a rectangular plot, ten 

 plants square if possible, hence known as a "centgener 

 plot." Notes are taken both on the centgener plot as a whole 

 and on individual plants, and recorded on sheets (see table on 

 opposite page, reduced size). 



1 See BulUti* Xo. 62, Minnesota Agricultural Experiment Station, for a full 

 description of the plot system as used at this station. 



