BLIGHTS OF CONIFEROUS NURSERY STOCK. 13 



Death from late frosts in the spring is rather frequent. Jack pine, 

 because of its tendency to start growth very early in the spring, fre- 

 quently loses its terminal buds and young shoots as the result of 

 severe frosts after growth has begun, although these young, tender 

 shoots are capable of standing a temperature considerably below 

 freezing without injury. Douglas fir nursery stock in the West also 

 seems to be quite susceptible to such injury. The use of some form 

 of shade to delay very early growth, placing beds of susceptible 

 species on high ground, and possibly the use of smudges, heaters, or 

 a temporary straw or burlap mulch on nights when frost is feared, 

 are methods which might be suggested for preventing spring frost 

 injury. 



EBERMAYER'S BLIGHT. 



In Germany, Ebermayer 1 states that death in pine nurseries re- 

 sults from sudden warm weather in early spring when the soil is so 

 cold that the roots are unable to absorb water normally and make 

 good the transpiration loss. The process which he described differs 

 from sun scorch in that it occurs oftenest on heavy soil and when the 

 soil contains excessive moisture. It differs from winterkilling in that 

 it occurs after the soil thaws. He states that the best method of pre- 

 vention is to decrease the transpiration loss by means of shade in the 

 early spring. This blight does not occur commonly in the United 

 States. 



DISEASES DUE TO PARASITIC FUNGI. 



NEEDLE-CAST. 



Lophoder?nium pinastri (Schrad.) Chev. causes the shedding or 

 " cast " of pine needles in German nurseries and plantations. The 

 disease is not known to occur in American nurseries, whatever may 

 be the case as to the presence of a fungus, but it is nearly certain to 

 make trouble in the future in moist localities. A brief account of 

 the disease, compiled from various statements of the great number 

 of European writers on the subject, will therefore be given. 



The disease has been known in Germany for more than a century 

 under the name of " schiitte." The causal relation of the parasite 

 was first reported in 1852, 2 but was not established till some years 

 later. When the parasitism of the fungus was established some 

 writers apparently accepted it as the only cause of blight, while 

 others, notably Ebermayer, who regarded physical factors as the com- 



1 Ebermayer, Ernst. Die Physikalischen Einwirkungen des Waldes auf Luft und 

 Boden. Bd. 1, Berlin, 1873, p. 251-261. 



Zur Schiittekrankheit der Kiefer. Allgenieine Forst- und Jagd-Zeitung, Jahrg. 77, p. 

 309-314, 1901. 



3 Goppert, II. R. [Hysterium pinastri als Ursache der Schiitte.] Verhandlungen, 

 Schlesischer Forst-Verein, 1852, p. 67. 



