158 NEBRASKA STATE HORTICULTURAL SOCIETY 



soil tbat would result in aiiplying gravel. It was also found at Halsey 

 that the disease was worse on ground newly broken than on areas that 

 had been in seed beeds foi- some time. 



Other Injuries. 



Red ants may cause damage especially to the seed. In field work 

 a good remedy is to keep wet crystals of potassium cyanide at the open- 

 ing and the ants burrow. In greenhouse experiments at the University 

 of Nebraska, ants have caused serious damage but were effectively dealt 

 with by using sulfur and salt at one time and carbon bi-sulfide at another. 

 Insect powder (Pyrethium has been used in some greenhouse work and 

 has been effective. 



Rodents, such as ground gophers, rabbits, mice and chipmunks occa- 

 sionally cause damage. The ground gophers often follow the rows short- 

 ly after seeds are planted and cause considerable loss. Trapping is 

 the best method yet devised. Chipmunks are also bad after the seed is 

 soM'n and may be killed by poisoned grain or shooting. Mice and rabbits 

 ai'e often worse during the winter of the second season or later and 

 should be poisoned or shot. As many as 318 mice have been killed on 

 one-half acre. .Mr. .J. M. Fetherolf devised a scheme of putting seed ia 

 a bucket of water which was so arranged that the mice could get into 

 the bucket, and in this way succeeded in killing all mice in the nursery 

 and around it. Rodents usually eat the largest seed species first and 

 gradually work down to smaller seeds. They have not been reported as 

 affecting Engelmann spruce (pieea eiia:eliuaiiiii) and balsam fir (ahies 

 balsamea). chipmunks have been noted affecting limber pine (piiius 

 Hexilis) worse than any other species, even noted after treating with red 

 lead. Birds sometimes pick at terminal buds. Red lead usually prevents 

 seed injury, but not always, as turtle doves have been known to eat treated 

 seed. Ehooting may be necessary. Blue .lays and magpies often pull 

 up seedlings just as they come throug the surface of the ground. 



Fertility and Soil Composition. 



Very few experiments have been performed in determining the 

 value of physical and chemical soil factors as influencing the growth 

 of seedlings and transplants and great work remains to be done along 

 such lines. Commercial nurserymen follow a definite system of rotating 

 seedlings with legumes and supplement the rotation by use of comercial 

 and animal fertilizers. Uniform light loams of moderate fertility are 

 recognized as producing compact, symmetrical and well developed root 

 sj^stems of higher grade than is produced on very heavy or very light 

 soils. Loams underlaid by limestone are said to be especially valuable 

 in developing a large proportion of trees with excellent root systems. 

 However, this field of work remains almost totally undeveloped in this 

 country and should be the field for exact experimentation in the near 

 future. State experiment stations with foresters on their staff and the 

 larger Forest Service nurseries are in a position to at least begin the 

 work. 



