harmful results ensue. Several experiences were given in 

 Michigan in which trees were injured far more from the 

 winter freeze in a dry than in a wet soil in the same orchard. 

 It is a matter of common observation among fruit growers 

 that twigs and buds which are more or less shriveled in winter 

 from lack of water or lack of maturity are almost invariably 

 winterkilled in cold winters. 



3. What Effects do Fertilizers have on Tree Growth, 

 and hence on susceptibility to cold? 



It has long been thought that fertilizers with any considerable 

 amount of nitrogen, as barnyard manure, cause trees to make 

 a heavy, rank, soft growth susceptible to freezing. This 

 theory finds expression in such statements as: "Hardy under 

 neglect;" "Tender under high culture." The majority of 

 the growers consulted in this investigation still hold that such 

 is the case, but a very considerable number of them, and 

 among them some of the best fruit growers in the two States, 

 say that trees are more likelv to suffer from cold if underfed 

 than if overfed. 



Their experiences indicate that vigorous vegetable growth 

 in early summer can be made of great service in counteracting 

 cold, and that half-starved trees, or those which have been 

 allowed to bear too heavily, are apt to suffer most from 

 freezing. The influence of the preceding crop was strongly 

 shown in orchards of all fruits last winter, 1917-18. In all 

 orchards where the trees bore a light crop the preceding 

 summer there was less injury than with trees that bore a full 

 crop. By using properly balanced fertilizers, by stopping culti- 

 vation at the right time, and by judicious pruning, so that the 

 growth can be kept firm, the top of the tree compact and the 

 branches well set with buds, conditions favorable to hardiness 

 can be obtained. It is common knowledge that late fall growths 

 are susceptible to winter injury of both wood and bud. 



4. Do Cover Crops protect Trees from Cold? 

 There were no conflicting opinions on this point. Growers 

 who had planted cover crops were agreed as to the value of 

 this method of protecting trees from winter freezing. Many 



