NURSE PLANTING SKLKGT COTTON SEED. 3 



PLANTING DISTINCT TYPES OF COTTON. 



One way in which seed of a valuable selection may be conserved is 

 by planting it with seed of another variety of cotton which is so 

 different that its seedlings can be distinguished and removed when 

 the stage for thinning has been reached, thus securing the advantages 

 of a heavy rate of seeding without the unnecessary waste of valuable 

 seed. To do this successfully, however, a careful choice of varieties 

 must be made. Obviously, the seedlings of each must possess dis- 

 tinctive leaf characters, so that in thinning only plants of the select 

 strain may be left to grow; otherwise, the purpose of selection would 

 be defeated, since the stock would be contaminated by crossing. 



It is doubtful whether two Upland varieties could be found whose 

 seedling characters are different enough to enable the breeder readily 

 to distinguish between them with accuracy; but the fact that other 

 nurse crops can be planted with safety renders unnecessary the selec- 

 tion of another variety of Upland for that purpose. 



The danger in planting combinations of varieties of the same 

 general type can be avoided by using varieties of distinct types. 

 The seedlings of Upland and Egyptian cotton, for example, can be 

 distinguished at a glance, thus enabling the breeder to remove either 

 kind with ease, according to which variety he is increasing. The 

 same is true also of Upland and Sea Island seedlings. But it is not 

 possible to mix Egyptian and Sea Island cotton with impunity, as 

 the seedlings of these two types are very difficult to distinguish. 

 Both lack the red spot at the base of the cotyledons which is so 

 characteristic of Upland varieties. Their cotyledons also are of a 

 lighter tint of green than those of most Upland varieties and have 

 a somewhat more distinctly waxy appearance. 



Asiatic types of cotton are even more distinct from Upland varie- 

 ties than is Sea Island or Egyptian, and since they do not cross with 

 American types thej' may be found useful in nurse planting. 



The value of Upland cotton as a nurse crop for Egyptian, or vice 

 versa, was demonstrated in a test at San Antonio. Equal lots of 

 delinted 1 Lone Star (Upland) and Pima (Egyptian) seed were 

 thoroughly mixed and then planted by means of a mechanical 

 planter in a row 264 feet long. When the seedlings were about 6 

 inches high it was possible to thin to an almost perfect stand of 

 either variety in any section of the row (fig. 1). 



PLANTING COTTON SEED WITH BEANS OR PEAS. 



A very simple and effective method of avoiding the waste of select 

 cotton seed and at the same time securing the desired crust-lifting 

 force of several seedlings is to plant beans or peas with the cotton 

 seed. This combination appeared especially advantageous at San 



1 See under " Delinting cotton seed for nurse planting" (p. 6). 



