annual ranges of temperature. Some attempts have also been made 

 to show that in a forest region more rain falls than in adjacent open 

 fields ; but this I shall not further consider, as I have elsewhere shown 

 that the measured differences are all due to the influence of the wind 

 on the catch of the rain gage and have nothing to do with rainfall 

 itself. All reliable observations show that the percentage of moisture 

 in the soil is larger under the forest than in the open air, and all 

 investigations show that the temperature of the soil is far more uni- 

 form under the forest than in the full sunshine. 



The proper conclusion to draw from these forest studies, in so far 

 as they relate to the question of the influence of climate on crops, is 

 simply that plants growing within the influence of a forest have a 

 somewhat different climate from those growing in the open field. 

 The amount of this influence will become a proper study when any 

 important crop is cultivated within a forest or under its influence, 

 which, however, is not now generally the case. 



The inverse question as to the influence upon general atmosj^heric 

 phenomena of the temperature and moisture of the thin layer of quiet 

 air within a region covered with a forest is one that may be relegated 

 to the future as being of minor importance in dynamic meteorology 

 and of still less importance in agricultural climatology. 



On the other hand, the distribution and quality of forest trees 

 affords a very important illustration of climatic influence. Indeed, 

 the forests themselves furnish a most important crop of lumber and 

 firewood, perhaps the most valuable crop recorded in the statistics 

 of the countrj^, and one whose relation to climate must be imj)ortant, 

 but, unfortunately, the statistics of annual forest growth are not yet 

 available for this stud}'. I have, therefore, deferred the considera- 

 tion of this branch of our subject to a future date, when perhaps 

 American forestry will be more fully developed. 



I shall omit the consideration of theories and experiments as to the 

 artificial improvement of the weather, especially the production of 

 rainfall, protection from hail and lightning, and the amelioration of 

 our hot winds. Although this subject is alluring, I hope the common 

 sense of the agricultural community will eventually indorse my con- 

 viction that, for the present, our wisest plan is to confine our study 

 closely to, first, the influence of sunshine, heat, moisture, and atmos- 

 phere on the growth of plants, on the nature of the seed, and on the 

 character of the crops; second, the influence of the quality of the seed 

 itself and of the richness of the soil on the crop ; third, how to choose 

 our seed, cultivate the ground, and protect the plant from frost, birds, 

 insects, fungi, etc., so as to secure a good crop in spite of adverse 

 natura. climatic conditions. 



In general, I have labored to put my data and conclusions before 

 (he reader so fully that, if a student, he may utilize this report as a 



