2G 



LABOiRATORY .STUDIES OF BUDS 



Ailil the agps of ;ill the existnii;- Imils, iii(livi(hially. Then divicJe 

 this total liy thi- whnle iiuiiiliei- nt l.inls. Tliis gives tlie average age 

 of thp buds. Iliiw olil is the. ohlest linil on ihe lii'auch ? Cat some of 

 the oldest ones open. Should you judge them to be still capable of 

 development, in case of need? 



Record in your notes all numbers and ages. 



Exercise XIII. Compar.\tive Vigor of Development 



Select a lateral branch of the ]Maple provided, showing a few years' 

 growth. Hold the branch in the position in which it grew. Certain 

 of the leaf scars now look upward, part of tliem to right or left (hori- 

 zontally), and part toward the earth. That is, there are two sets, 

 the vertical (above and below) and the horizontal. In each set count 

 the whole number of paiis of leaf scars; also the number (pairs) 

 where the buds have made some growth. 



Record in a table like the following : — 



Measuic roughly th'' combined length of all the horizontal twigs 

 developeil from latnral buds. Condiined length of vertical twigs. 

 Compare the numliei's obtained tljus ; — 



Total length of all horizontal twigs 



Total length of all vertical twigs 



Count the whole numljer of present winter buds on all the twigs of 

 each set separately. This gives a hint as to their comparative vigor. 

 Record thus : — 



Huds on horizontid twigs 



Ibids I Ml vertical twigs 



Is there any advantage to the tree in the superior development of 

 one system over Ihe other? 



This exercise is intendeil to bring out two facts; first, that certain 

 buds are more likelv to devnlop than others; second, that certain buds 

 develop more vigorouslv than others. The exei-cise is not intended to 

 teach — what would not be universally true — that the horizontally 

 directed buds. f(jr example, are <ihcni/s more vigorous than vertically 

 directed buds ; or cice i-ersa. 



