176 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



mies in the use of timber. Among these will be found the original 

 investigations into the structure and use of certain railroad ties by 

 Mr. P. H. Dudley, C. E., of New York; experiments in regard to the 

 adhesion of sj^ikes and the economy of different methods of fastening; 

 a review and practical elucidation of different methods for the pres- 

 ervation of timber, by Col. H. Flad, C. E., of Saint Louis, and Mr. H. 

 Constable, C. E. , of New York, and an exhaustive report on metal ties, 



A report on the relation of charcoal iron works to forestry has been 

 prepared by Mr. J. Birkinbine, secretary of the Charcoal Iron-Work- 

 ers' Association. Reports on the use of timber in mining enterprises 

 and on the state of wood manufactures are in preparation. 



It was thought that by such reports those interested in these indus- 

 tries might be aroused to the necessity of securing a continuance of 

 supplies, and as many of the industries are carried on by owners of 

 forest lands, their action leading to an economical and systematic 

 management of these might be secured. 



PHENOLOGICAL OBSERVATIONS. 



The desirability of interesting our educational institutions in the 

 work of forestry reform, which has been so strongly emphasized by 

 some forestry advocates, has not been ignored. To bring the agricult- 

 ural colleges and their students into active sympathy with the work 

 of the Division, schedules for observations of plant development, re- 

 lating notably to the date of the flowering, leafing, and fruiting of 

 trees, were sent to the professors of botany for distribution among 

 advanced students. To enlarge the class of observers, the members 

 of the Agassiz Association, at their request, as well as private appli- 

 cants, were supplied with schedules, so that quite a large corps of ob- 

 servers were engaged upon this work. By thus inviting students to 

 personal and methodical observation of tree-life, under the direction 

 of and in connection with the Forestry Division, it was hoped that such 

 an interest might be incited as is thought to be essential to our future 

 forest policy. 



The principal aim of such observations, to be carried on through a 

 series of years under certain prescribed conditions, is to arrive at 

 some practical points of climatic comparison, or, as stated on the 

 schedule: 



(1) To note the progress of local development in tree life, for the purpose of en- 

 larging the knowledge of biological conditions. 



(2) To arrive at conclusions as to relative climatic conditions expressed by phases 

 of plant development, and also, ince versa, as to dependence of such developments 

 on such conditions. 



(3) To determine the period of vegetation of different species (time from appearance 

 of first leaf to general change of foliage). 



(4) To ascertain the relative dependence of different species on climatic conditions, 

 determining relatively the time for planting. 



(5) To furnish comparison of the Isehavior of the same species under the climatic 

 conditions of different localities, thus allowing preliminary estimates of the capacity 

 of the species for acclimation.. 



It cannot be denied that the complex factors which we designate 

 under the comprehensive term "climate" find most readily a satisfac- 

 tory expression in the development of plants, and therefore, if by 

 observations continued for many years on the same individual plants 

 in different parts of the country we can establish the average occur- 

 rence of a certain plant phase, for instance the flowering, we shall 

 gain pretty safe points for comparison between the climatic conditions 



