STOIiliS AGlilCULTDEAL EXl>EliIMENT STATION". 317 



in the Swert C'Iktit (p. 503) and tlio Black Bireli (p. Jzl-'ij and 

 the arraugenient of the hranchlels whether opposite or alter- 

 nate and whether erect or drooping, may further be mentioned 

 as habit characters. 



As one becomes more familiar willi ti-ces in their winter aspect, 

 the nrmiber that cannot be recognized at a distance becomes greatly 

 diminished. We come to know trees by hardly definable traits, 

 much as we recognize our friends at a distance by some peculiarity 

 of forur or gait. Watching the trees from a car window is a great 

 help in ac((uiring this familiarity with the habit cliaracters. The 

 method of branching and other features included in the habit, 

 liowever, do not furnish such precise marks as do the twigs, and 

 cannot therefore be of much value in a descripti\e key. In fact the 

 habit varies considerably among individual trees of the same 

 species, no two trees having exactly the same method of branch- 

 ing. Moreover trees grown in woods in company A\-itli other 

 trees are pre\ented by lateral shading from developing their normal 

 form and produce tall trunks with but little branching. On the 

 other hand trees apart from other trees have usually been j)lauted 

 for ornament or have originally grown in "woods but have beeri 

 left isolated by the cutting down of their neighbors. In the latter 

 case the habit will be more or less that ol a forest-grown tree 

 dependent upon the age at which the conditions of light and 

 shade were altered (see lower habit picture ]"i. 4G3). In the 

 former case the top of the young tree may have been cut in the 

 process of transplanting causing an increased branching at the 

 point of cutting and the lower limbs may have been trimmed off, 

 o-ivins; a sreater show of trunk. These mutilations, however, have 

 less influence upon the outline of the head or crown than might 

 be imagined since the tree is generally able to accommodate itself 

 to such accidents as those mentioned and express its individuality 

 despite them. The age of the tree is also an important factor in the 

 outliire, young specimens being in general narrower and more coni- 

 cal than in later life while those in old age may have lost shape 

 through ice storms, high winds and the attacks of fungi. 



So far as possible the photographs have been taken from mature 

 specimens growing in the open and only those have been chosen 

 which have been considered to present an appearance typical of 

 the species. They will help one to form a mental picture of those 



