18 FORESTRY BULLETIN 



RELATION OP METEOROLOGY TO FORESTRY IN MICHIGAN. 



BY E. C. KEDZIE. 



The controlling inauence of climate over forest growth is well recog- 

 nized. The distribution of plants over the earth's surface is to a large 

 extent determined by climate, but moisture as an element of climate is 

 controlling. The climatic conditions, as related to forest growth, and 

 especially in connection with the question of reforesting our denuded 

 northern plains become matters worthy of consideration. 



FOREST GEOWTH. 



The conditions favorable to growth of trees are good soil, proper temper- 

 ature and moisture. Failure of any one of these will limit or prevent 

 arboreal growth. A good illustration of the limitation by a poor soil 

 is furnished in the government forests, of Germany. Prof. F. S. Kedzie 

 in a recent letter writes: "I have been all over the Royal Forest. It 

 lies outside of the city about ten miles and is carefully watered and taken 

 care of by a small army of foresters. The trees are all pines, planted 

 a great many years ago, and through the forest run wild boar, deer and 

 other game. I saw one lone red squirrel during my tour, which lasted 

 over four hours. Only the Kaiser and his guests ever shoot or hunt the 

 game here. * « » * At one point I found a plot of pines which was 

 planted in 1889, but the result must try even the patience of a German — 

 the average height was not more than four feet. 



I was disappointed in the appearance of the trees in the forest — they 

 don't compare with ours at home, and I expected they would be much 

 larger on account of the more abundant rainfall. When I told the Ger- 

 man friend who was with me that they were beginning to agitate the 

 forest question in Michigan he seemed greatly astonished that a man was 

 permitted to cut down trees without planting as many acres as he cleared. 

 There is one thing clear to my mind; we don't need to try any experi- 

 ments in forestry with pine trees — the millennium is too near." 



The limiting conditions for forest growth are not found in our soil, 

 which is in striking contrast with the thin sands of Prussia; but in cer- 

 tain sections the climatic condition, especially the rainfall, is the problem 

 to be solved. While the climate of Michigan on the average is satisfac- 

 tory, yet it still must be characterized as capricious — subject to wide vari- 

 ations from year to year. The influence of these climatic variations is 

 shown in corresponding variations in tree growth. Spruce trees have 

 grown for many years on the college lawn. When cut down, and a 

 cross section of the trunk is examined, the concentric layers of annual 

 growth clearly point out the good years of abundant rainfall, while the 

 thin rings show the years of unfavorable climatic conditions. The mete- 

 orological tables for the last 34 years at this college, when compared with 

 "the tables in wood" of ajinual growth, show very clearly the relations of 

 climate to forest growth. 



