NEEDLE-CAST. 687 



Emmerling* states that sowings of 1-year-old pines in the 

 North German heather-land suffer severely every year from 

 needle-cast, whilst those on the more favourable, sandy loam 

 are not affected by it. 



It is clear that Scots pine is affected by needle-cast on all 

 kinds of soil, but that on loam the plants are stronger and 

 escape the danger better than on poor sand. 



d. Soil-cover iiKj. 



It is not yet decided what influence the nature of the soil- 

 covering has on the disease. It may, however, be laid down 

 as a general rule that ground covered with grass or weeds 

 is less liable to it than bare localities, but the favourable 

 influence of the soil-covering may be counterbalanced by 

 other causes. 



e. System of Manaf/ement. 



Under a shelterwood, the young pines may entirely escape 

 the disease, or suffer only slightly, and lateral shelter from old 

 pine- woods acts favourably by reducing insolation and radiation 

 of heat from the ground. On large clearings, pines are almost 

 always subject to needle-cast. Areas densely sown late in 

 the year suffer most of all, when the individual plants have 

 very small root-systems and thin elongated stems. 



/. Weather. 



The disease is most frequent in March, April and May, 

 and a wide range of temperature, such as warm sunny days 

 and cold nights with rime, favours it. Cold, dry easterly 

 or north-easterly winds increase the evil. During cloudy, 

 rainy weather in spring, the disease may not appear at all, or 

 only slightly. It is also more frequent after damp winters 

 with light snowfall than after the ground has been well 

 covered with snow. 



3. Geographical Range. 



The disease occurs wherever the Scots pine is cultivated, 

 but is less common in colder countries, such as Russia. It 



* " Untersuchuiig uber die Ureache <ler Kiefernschiitte in Schleswig-Holstein," 

 by Dr. A. Euimeiling and Dr. G. Loges, " Alig. Frst. u. Jgdztg.," 1882, p. 13.5. 



