30 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I40 



ployed the presence of terminal bud scale scars counted inward on 

 the branch. This method in itself is not considered universcJly ac- 

 curate in setting off increments of annual increase in length, a fact 

 to be elaborated under the chapter on multiplicity. In truth, it was 

 found that a disparity between the number of tip flushes and the 

 number of diameter flushes in many cases provided a key to multi- 

 plicity of growth flushes within one year. 



Terminal bud scale scars were used in two ways : first, where the 

 internodes were actually measured; and second, where they were 

 merely counted. 



The following species in the Lubbock area came under the first 

 heading, actual measurements : Conifers — ponderosa pine (4 trees, 

 15 branches), loblolly pine (2 trees, 3 branches), and a short-leafed 

 yellow pine (MP i ; i tree, i branch). Dicotyledons — apple (3 trees, 

 14 branches), ash (i tree, i branch), cottonwood (i tree, 2 branches), 

 honey locust (3 trees, 6 branches), silver maple (2 trees, 7 branches), 

 sycamore (i tree, i branch), and vitex (i tree, 2 branches). These 

 totaled 52 branches from 19 trees of 10 different species. Under the 

 second heading for the Lubbock area, terminal bud scale scars were 

 counted, with total measurement to the sections taken but no meas- 

 urement on individual internodes, on the following species : Conifers 

 — ponderosa pine (4 trees, 19 branches). Dicotyledons — Siberian 

 elm (2 trees, 6 branches), cottonwood (i tree, i branch), honeylocust 

 (2 trees, 2 branches), and silver maple (i tree, i branch). 



The second type of use of terminal bud scale scars, counting only, 

 included the following species from northern New Mexico : Conifers 

 — ponderosa pine (2 trees, 2 branches), foxtail pine (2 trees, 2 

 branches), limber pine (i tree, i branch), corkbark fir (2 trees, 2 

 branches), white fir (i tree, i branch), and Englemann spruce 

 (3 trees, 3 branches). Dicotyledons — alder (i tree, i branch), aspen 

 (i tree, i branch), gooseberry (2 bushes, 2 branches), and willow 

 (4 trees, 4 branches). The total of counted terminal bud scale scars 

 came to 48 branches from 29 trees of 20 different species. 



As a matter of passing interest, a grand total of tip-growth meas- 

 urements was made upon 576 branches from 72 different trees dis- 

 tributed among 12 coniferous and 17 dicotyledonous species. 



The data on tip growth so far described have depended upon ac- 

 curate measurements at either regular or irregular time intervals. 

 In addition to such measurements, many direct and sustained ob- 

 servations were made — observations made at intervals which ranged 

 all the way from daily to several weeks. These observations were of 

 three types: First, close observations of the branches immediately 



